Cambro-Ordovician magmatism in the Delamerian orogeny: Implications for tectonic development of the southern Gondwanan margin

Journal Pre-proof Cambro-Ordovician magmatism in the Delamerian orogeny: Implications for tectonic development of the southern Gondwanan margin

John Foden, Marlina Elburg, Simon Turner, Chris Clark, Morgan L. Blades, Grant Cox, Alan S. Collins, Keryn Wolff, Christian George PII:

S1342-937X(20)30020-4

DOI:

https://doi.org/10.1016/j.gr.2019.12.006

Reference:

GR 2275

To appear in:

Gondwana Research

Received date:

13 August 2019

Revised date:

8 December 2019

Accepted date:

8 December 2019

Please cite this article as: J. Foden, M. Elburg, S. Turner, et al., Cambro-Ordovician magmatism in the Delamerian orogeny: Implications for tectonic development of the southern Gondwanan margin, Gondwana Research(2020), https://doi.org/10.1016/ j.gr.2019.12.006

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© 2020 Published by Elsevier.

Journal Pre-proof

Cambro-Ordovician Magmatism in the Delamerian Orogeny: Implications for Tectonic Development of the Southern Gondwanan Margin John Fodena, Marlina Elburgb, Simon Turnerc, Chris Clarkd, Morgan L. Bladesa, Grant Coxa, Alan S. Collinsa, Keryn Wolffa & Christian Georgea

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Department of Earth Science, University of Adelaide, Adelaide 5005, Australia Department of Geology, University of Johannesburg, Johannesburg 2006, South Africa c Department of Earth and Planetary Sciences, Macquarie University Sydney 2109, Australia d School of Earth and Planetary Sciences, Curtin University, Perth 6845, Australia

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Abstract.

The Delamerian Orogen formed at the final stages of assembly of the Gondwana supercontinent. This system

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marks the initiation of subduction of the Pacific oceanic lithosphere along a prior rifted and extended passive

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margin. This paper explores the magmatic consequences following the early Cambrian initiation at the palaeo-Pacific margin in South Australia (SA) and western Victoria. Our data reveal a 50 Ma syn- to post-

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Delamerian tectono-magmatic history. Sampled from drill core from beneath the eastern Murray Basin cover in eastern SA, boninitic high Mg andesite from drill hole KTH12 and 516.1±2 Ma quartz diorite suggest that

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first subduction established a volcanic arc within easternmost SA. Pacific-ward trench retreat then resulted in arc migration to reach the Mt Stavely Belt and Stawell Zones in western Victoria by ~510 Ma where boninitic arc magmatism continued until ~490 Ma. In the SA foreland of the Delamerian Orogen, early (522 ± 4 Ma) alkali basalt gave way to intrusion and extrusion of MORB-like tholeiites of back-arc basalt character. Through much of the middle and late Cambrian the SA Delamerian was in the back-arc and under extension but with periodic compression resulting from periodic Pacific-Australian plate coupling beneath the forearc in western Victoria. In SA syn-tectonic I- and S-type granites reflect interaction of MORB-like back-arc magmas and their transported heat with continental-derived sediment of the Kanmantoo Group. The termination of the Delamerian orogeny at ~490 Ma was accompanied by buoyancy-controlled, exhumation and erosion. This

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Journal Pre-proof was driven by delamination of a mafic, crustal underplate, whose re-melting at 1.5 to 2 GPa and 1050oC generated the unique 495 ± 1 Ma Kinchina/Monarto adakite. Delamination resulted in lithospheric mantle thinning and local convective overturn allowing upwelling of the asthenosphere to drive the post-kinematic magmatic phase of the Delamerian, yielding voluminous 490 Ma – 470 Ma A-type granites.

2. Introduction 2.1 The Supercontinent Cycle

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Nance et al. (1988), building on ideas by Worsley et al. (1984; 1986) realised that the plate tectonic evolution

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of ocean basins divided into those oceans that opened and closed at approximately their same location—as

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Iapetus appears to have done (Wilson, 1966). These introverted oceans broke up and reformed larger continental masses in the same general location. Whilst other ocean basins were longer lived and only closed

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when, a major supercontinent extroverted and dispersed, later coalescing in a different configuration at a

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vastly different location. This became the genesis of the supercontinent cycle, where continents periodically recombine either by introversion or extroversion. In both extroversion and introversion, continent

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coalescence due to subduction of oceanic lithosphere, in front of the leading edges of continental fragments, requires the trailing margins of the assembled continental plates to eventually change from rifted passive

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margins to subduction margins (Nance et al., 2014). This involves the ‘spontaneous’ development of new subduction zones (Stern and Gerya, 2018). There is an important distinction between those orogenic zones that result from the convergence, collision and suturing of accreting continental fragments that come together to form new supercontinents, and those orogens formed at the ocean-facing trailing margins of these fragments. Each of these scenarios should be characterised by a unique and distinctive time series of magmatic events. The late Neoproterozoic to Cambrian Delamerian-Ross-Saldanian Orogen (Scheepers et al., 2002, S. African Journal of Geology, 105, 241-256) was formed along the palaeo-Pacific margin coeval with the assembly of continents that were mostly derived from rifting of the earlier Rodinian supercontinent (Merdith et al., 2017a). This a key example of the development of an orogeny formed at an ocean-facing passive margin that transits to become a subducting margin (Foden et al., 2006). In this paper we examine

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Journal Pre-proof the geochemical and petrogenetic response of Cambrian magmatic rocks from the South Australian and western Victorian sector of the Pacific–facing Gondwanan margin to this critical transition.

2.2 Pacific-Facing Margin of Gondwana The Neoproterozoic to early Cambrian assembly of the Gondwana supercontinent was achieved by a series of subduction-controlled ocean closures and arc accretions (Collins and Pisarevsky, 2005; Meert, 2003; Merdith et al., 2017a). Regular accretion and minor collision occurred around continents that became

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Gondwana through the Neoproterozoic, but the main amalgamation of Gondwana was focussed at the end of

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the Ediacaran and into the Cambrian (580–520 Ma, Collins and Pisarevsky, 2005; Li et al., 2008; Merdith et al., 2017a; Schmitt et al., 2008). These amalgamations created the palaeo-Pacific-facing southern

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Gondwanan margin that ran continuously from northeast Australia to the Kalahari craton margin in southern

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Africa and on to southern South America via the south-facing margin of East Antarctic. This southernmost

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edge of the newly agglomerated Gondwana had an initially passive margin with respect to the Pacific until the period between the late Neoproterozoic to mid Cambrian during which time progressive onset of

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subduction took place reflected as the Saldanian-Ross-Delamerian orogenies. These events marked the start of the long-lived orogenic system on this Pacific margin establishing the so-called Terra Australis Orogen

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(Cawood, 2005). Some evidence (Foden et al., 2006) suggests that initiation of this orogenic system may have commenced first in the west around the margin of the Kalahari Craton in southern Africa, forming the Ediacaran Saldanian Orogeny followed by the Antarctic Beardmore/ Ross orogenies and finally extending eastwards to the Australian mid–late Cambrian Delamerian Orogeny (Boger and Miller, 2004; Foden et al., 2006; Goodge et al., 2012).

3. The Delamerian and its Magmatic Record in NSW, Victoria, SA & Tasmania The Delamerian Orogeny resulted from the Cambrian tectonic inversion (to become a subducting plate margin; e.g. Foden et al., 2006, Finn et al., 1999) of the Neoproterozoic and early Cambrian sedimentdraped, rifted, cratonic margin of Australia. It initiated the characteristic tectonic style that has characterised the west Pacific margins to the present day. This character is one of repetitive ocean-ward slab rollback and

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Journal Pre-proof upper plate extension with relatively brief interludes of upper plate compression and deformation. The Delamerian Orogen is characterised by craton-ward (now westward) vergent folding and thrusting (Flöttmann et al., 1998), by localised low P-high T metamorphism and migmatite development (e.g. Alias et al., 2002; Dymoke and Sandiford, 1992; Offler and Fleming, 1968; Schwindinger and Weinberg, 2017) and is associated with a complex magmatic history with ages ranging from early Cambrian to early Ordovician (Foden et al., 2006; Foden et al., 2002a; Gray et al., 2002; Johnson et al., 2016; Kemp, 2003; Lewis et al., 2016; Mortensen et al., 2015).

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The character of the Delamerian was strongly influenced by the Rodinian break-up history that preceded it and formed the palaeo-Pacific-facing passive margin. The first stages of continental rifting are

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recorded in South Australia by the Callana Group, the earliest unit of the Adelaidean Supergroup (Preiss,

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2000). This group hosts the ~830 Ma (Wingate et al., 1998) Wooltana-Depot Creek tholeiites (Crawford and

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Hillyard, 1990) Direen and Crawford (2003) suggested that there was a second phase of rifting at ~585 Ma, which generated the Mt Arrowsmith alkali basalts in western NSW. They interpreted this to mark onset of

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accelerated drift and the production of a magmatic passive margin with recognisable seaward-dipping

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reflectors. Although other authors dispute this explanation (Gibson et al., 2015) there are other Australian examples of ~585 Ma magma-rich passive margin fragments, notably on King Island (Direen and Jago,

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2008; Meffre et al., 2004). Recently, Merdith et al. (2017b), demonstrated that a late separation of Laurentia from Australia is not kinematically feasible using Phanerozoic plate velocities. These authors strongly support a late Tonian or earliest Cryogenian formation for the Pacific. In Australia, elements of the Cambro-Ordovician Delamerian Orogen can be identified fringing the rifted margin of the older Palaeo- to Mesoproterozoic cratonic basement from northern Queensland to Tasmania. This belt was contiguous with the Antarctic Ross Orogen exposed in Northern Victoria Land and the Transantarctic Mountains continuing across Antarctica to the Weddell Sea and then to southern Africa (Cawood, 2005; Greenfield et al., 2011; Stump, 1995) and to the Sierra de la Ventana region of Argentina. In southern Australia, the Delamerian is exposed in South Australia (see below), in the Koonenberry belt of western New South Wales (Direen and Crawford, 2003; Greenfield et al., 2011; Johnson et al., 2016) and in the Glenelg (Gibson and Nihill, 1992; Gray et al., 2002; Kemp, 2003; Turner et al., 1993) and Mt Stavely (Bowman et al., 2019; Crawford et al., 2003; Squire et al., 2006) terranes in western Victoria. Tectonic

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Journal Pre-proof events synchronous with the mainland Australian Delamerian are also recognised in Western Tasmania, sometimes referred to as the Tyennan Orogeny, (e.g. Berry et al., 2007), though its provenance and the timing of its arrival at the Gondwanan margin remain in debate (Cayley, 2011; Moore et al., 2016). Rocks in Tasmania preserve a complex history of Cambrian deformation and metamorphism of Neoproterozoic metasediment-dominant terranes (Berry et al., 2007; Meffre et al., 2000) associated with early to midCambrian tholeiite and boninite production (Crawford and Berry, 1992) and the late Cambrian, largely felsic to intermediate composition Mt Read volcanics (Crawford et al., 1992; Mortensen et al., 2015).

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The Delamerian Orogen is most widely exposed in South Australia and is described in an extensive literature. Formed by the middle to late Cambrian deformation (Flöttmann et al., 1998; Flöttmann et al.,

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1994) of the Neoproterozoic Adelaidean Supergroup (Preiss, 2000) and early Cambrian sequences that

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include the Normanville Group and its successor Kanmantoo Group (Haines et al., 2009; Jago et al., 2003),

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the outcropping orogen is referred to as the Adelaide Fold Belt (AFB). It is exposed to form the Flinders Ranges to the north, becoming the Adelaide Hills further south towards Adelaide and then running further

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south as the Fleurieu Peninsular and curving west to form Kangaroo Island. This topographic exposure of the

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Cambrian orogen in South Australia is a neotectonic feature due to Cenozoic uplift (Sandiford, 2003) and exposes only the foreland of the orogen (Flöttmann et al., 1998). Only 50 km further to the west on the

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Gawler Craton, Neoproterozoic and early Cambrian strata are thinly bedded and undeformed. The TMI imagery (Fig. 2) clearly indicates that the orogen is ~300 km wide eastwards from the Adelaide Hills to the Mt Stavely belt at its eastern margin at the western edge of the Lachlan Fold Belt. This margin is defined by the Moyston and Stawell-Ararat faults in western Victoria (Foster et al., 2009; Gray and Foster, 2004). There is very little outcrop across much of this eastern two thirds of the belt and within South Australia most of this obscured terrane is mantled by cover of Mesozoic to Cenozoic terrestrial and shallow marine sediments of the Murray Basin. Facilitated by sampling opportunities provided by quite numerous drill core intersections of the Cambrian basement beneath the Murray Basin cover (Figs. 1,2 ; Table 1), this study aimed to provide a more complete geochemical coverage of igneous activity spanning the gap between the orogen’s foreland in the exposed ABF and its Cambrian Pacific margin to the east. The TMI image also clearly shows the northward extension of the Delamerian belt. It swings sharply northeastwards (the Loch Lilly-Kars Belt; Greenfield et al., 2011) around the projecting Palaeoproterozoic

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Journal Pre-proof Curnamona Craton before swinging back north westwards to form the Bancannia Trough, the Wonnaminta Zone and the Kayrunnera Zone that make up the Koonenberry Belt (Greenfield et al., 2011; Johnson et al., 2016).

3.1 Adelaide Fold Belt. Outcrop in the Southern Adelaide Fold Belt (SAFB) records a dramatic early Cambrian shift in the basin architecture and sedimentary record (Preiss, 2000) and provenance (Ireland et al., 1998). The Cambrian

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Normanville Group consists of carbonates and records rapidly increasing water depth towards the thin-

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bedded turbidites of the Heatherdale Shale, which have recently been dated at 514.98 ± 0.22 Ma (Betts et al., 2018). The Normanville Group hosts the Truro Volcanics (Foden et al., 2002a; Forbes et al., 1972) a 522 ± 2

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Ma (Jenkins et al., 2002) suite of undersaturated anorogenic style alkali basalts. The Normanville Group is

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overlain by the dramatic influx of thick-bedded siliciclastic-rich turbidites that mark the base of the

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Kanmantoo Group (Flöttmann et al., 1998; Haines et al., 2009; Jago et al., 2003). The very rapidly deposited Kanmantoo Group which marked the abrupt initiation of sediment supply to a very deep and necessarily

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steep walled basin (Flöttmann et al., 1998). The provenance of this sediment was very different from that of the prior Neoproterozoic sequences and includes a new prominent 550–560 Ma source (Ireland et al., 1998;

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Keeman et al., In submission). It occupies a wedge-shaped area in the south of South Australia. At its southern end it extends from western Kangaroo Island, east to the western Victorian Glenelg Terrane (Harvester’s Creek greywacke) and tapers to a closure in the state’s middle north. There is a large gap in its exposure to the east of the Adelaide Hills, where it is obscured by the Murray basin. The western part of the Delamerian Orogen is exposed in the AFB, where an early D1 fold-thrust phase of deformation is recognized (Flöttmann et al., 1998). This has been interpreted to have terminated Kanmantoo sedimentation, perhaps as early as ~515 Ma (Foden et al., 2006) or a little later (Betts et al, 2018). Evidence for further deformation continued until 490 ± 5 Ma (Foden et al., 2006). Associated with low P-high T metamorphism and magmatism, three distinct deformation episodes have been recognised within this time interval. The initial thrust-dominant D1 event was followed by D2 and D3 upright folding events (Alias et al., 2002; Flöttmann et al., 1998; Offler and Fleming, 1968).

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Journal Pre-proof The outcropping AFB hosts both felsic and mafic intrusive magmatic suites (Foden et al., 2006; Foden et al., 2002a). Though not completely exclusive, by far the majority of the magmatic rocks intrude the Kanmantoo Group. In contrast to the Truro alkali basalt lavas in the Normanville Group the Kanmantoo Group hosts mafic sills or dykes of tholeiitic composition (Chen and Liu, 1996; Foden et al., 2002b; Liu and Fleming, 1990). The AFB also hosts syn-tectonic I- and S-type granite intrusions (Foden et al., 2006; Foden et al., 2002a; Foden et al., 2002b; Milnes et al., 1977) with ages in the range 515490 Ma. In the SAFB the last stage of Delamerian contraction at 490 ± 5 Ma was directly followed by undeformed 490485 Ma diorite

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and felsic dyke intrusion. Further east, outcropping as isolated granite tors, an extensive suite of post-tectonic (<490Ma) A-type granites and volcanics with some contemporaneous mafic bodies can be found. These

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intrusions create the magnetically prominent 500 km Padthaway Ridge extending with NNW–SSE

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orientation into SW Victoria (Turner et al., 1993; Turner and Foden, 1996; Turner et al., 1992).

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3.2 Glenelg River Complex

The Delamerian Orogen obscured by the Murray Basin in the east of South Australia, reappears in outcrop in

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the Glenelg River Province in western Victoria (Gibson et al., 2015; Gibson and Nihill, 1992; Gray et al., 2002; Kemp, 2003; Kemp et al., 2002; Turner et al., 1993). The Glenelg River Complex has a geological

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history that closely matches that of the SAFB, though unlike the AFB it does contain fault-bound serpentinised peridotite bodies (Turner et al., 1993). The Harvester’s Creek greywacke is a siliciclastic turbidite sequence that is equated with the Kanmantoo Group and perhaps the Normanville Group (Gibson et al., 2015). The sequence has a poly-deformational history that also ceased at ~490 Ma and it hosts both synand post-tectonic I- and S-type granites (Kemp, 2003; Kemp et al., 2002). Like the Kanmantoo there are layer-parallel intrusive bodies of tholeiitic metagabbros with E- to N-MORB compositions as well as aluminous calc-alkaline gabbros (Gray et al., 2002). Gibson et al. (2015) also report alkaline mafic bodies in the metasedimentary sequence and these may be equivalent to the Truro volcanics in the SAFB. Significantly, Kemp (2003) reports gabbroic and dioritic syn- and post-deformation intrusions of boninitic affiliation.

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Journal Pre-proof 3.3 The Mt Stavely Volcanic Complex The Mt Stavely Volcanic Complex (Crawford et al., 2003; Schofield et al, 2018, Lewis et al., 2016) is ~70 km east of the Glenelg River Complex. Described as a volcanic arc (Bowman et al., 2019; Foden et al., 2006), it comprises slightly metamorphosed basaltic, andesitic and dacitic lavas, dacitic porphyry and tuffs and volcaniclastic sediments ranging in age from 510 to 503 Ma (Lewis et al., 2016). Deformation ceased here at ~498 ± 5 Ma. (Bushy Ck.Granodiorite). The volcanics are within variably deformed siliciclastic sediment sequences (Nargoon Group and the Glenthompson Beds). The Mt Stavely Complex is

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bound to the east by the Moyston Fault (Miller et al., 2005) and between this and the Ararat Fault a further

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20 km to the east is the Stawell Zone which hosts a sequence of Cambrian basalts (the Magdala Basalts, e.g.

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Squire et al., 2006).

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3.4 The Koonenberry Belt.

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The Koonenberry Belt hosts a sequence of early to mid-Cambrian sedimentary units (Gnalta, Ponto and Taltawongee groups) that were deformed by the Delamerian Orogeny and which host syn-tectonic granite

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(Williams Peak Granite; 515±2.4 Ma; Black, 2007) as well as a range of tuffs and volcaniclastic sediments and the calc alkaline, 508 ± 3 Ma Mt Wright Volcanics (Greenfield et al., 2011; Johnson et al., 2016; Mills,

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1992). Here the Delamerian unconformity has a maximum age of 496.3 ± 3.1 Ma (Black, 2006) and is succeeded by post-tectonic mafic magmatism in the overlying Kayrunnera Group (Greenfield et al., 2011). In the Koonenberry Belt, Johnson et al. (2016) favour a model of west-dipping subduction commencement at 515 Ma, the same timing as that suggested by Foden et al. (2006) for the AFB.

4. Methods 4.1 U-Pb Geochronology Rock samples were crushed and the zircon fraction (sieved 79–425 μm) was separated by panning. Zircons were hand-picked and mounted in epoxy resin. Zircon U-Pb geochronology was undertaken at the University of Adelaide using an Agilent 7500 ICP-MS with attached New Wave Nd-YAG laser ablation system. A spot size of 29 µm and frequency of 5 Hz (fluence = 4.5J/cm2) was used. Isotopes 90Zr, 201Hg, 204Pb, 206Pb, 207Pb,

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Journal Pre-proof 208

Pb, 232Th and 238U were measured. Each analysis comprised a 20s background and 30s ablation. GEMOC

GJ-1 zircon (TIMS normalising ages 207Pb/206Pb = 607.7 ± 4.3 Ma, 206Pb/238U = 600.7 ± 1.1 Ma and 207

Pb/235U = 602.0 ± 1.0 Ma; Jackson et al. 2004) was used to correct for U–Pb fractionation. The Plešovice

zircon standard (ID TIMS 206Pb/238U = 337.13 ± 0.37 Ma; Sláma et al., 2008) was used to assess accuracy over the course of the laser session; a total of 52 Plešovice standard analyses were made and yield a weighted average 206Pb/238U age of 338.41± 0.69 Ma (95% confidence limits) which closely matches the ID TIMS age. Data were corrected using GLITTER version 3.0 (Van Achterbergh et al., 2001) and Concordia diagrams

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and weighted averages were calculated using IsoplotR (Vermeesch, 2018).

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4.2 Ar-Ar Geochronology

Samples were loaded together with standard Hb3gr hornblende for which an age of 1073.6 ± 5.3 Ma was

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adopted (Jourdan et al., 2006) and were irradiated for 25 h in the Hamilton McMaster University nuclear

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reactor (Canada). J-values were computed from standard grains. Mass discrimination was monitored using an automated air pipette. The correction factors for interfering isotopes were (39Ar/37Ar) Ca= 7.30 × 10− 4 (±

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11%), (36Ar/37Ar) Ca= 2.82 × 10− 4 (±1%) and (40Ar/39Ar) K= 6.76 × 10−4 (±32%). The 40Ar/39Ar analyses

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were performed in the Western Australian Argon Isotope Facility at Curtin University using techniques previously described in detail (e.g. Li et al., 2014). For each sample, single crystal was step-heated using a

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110 W Spectron Laser Systems, with a continuous Nd-YAG (IR; 1064 nm) laser rastered over the sample during 1 min to ensure a homogenously distributed temperature. Ar isotopes were measured in static mode using a MAP 215-50 mass spectrometer (resolution of ~450; sensitivity of 4 × 10−14 mol/V) with a Balzers SEV 217 electron multiplier using 9 to 10 cycles of peak-hopping. The raw data were processed using the ArArCALC software (Koppers, 2002) and the ages have been calculated using the decay constants recommended by Steiger and Jaeger (1977). Blanks were monitored every 3 to 4 steps and typical 40Ar blanks range from 1 × 10−16 to 2 × 10−16 mol. Ar isotopic data corrected for blank, mass discrimination and radioactive decay are given in Table 2. Individual errors are given at the 1σ level. Criteria for the determination of plateau are as follows: plateaus must include at least 70% of 39Ar. The plateau should be distributed over a minimum of 3 consecutive steps agreeing at a 95% confidence level and satisfying a probability of fit () of at least 0.05.

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Journal Pre-proof 4.3 Nd-Sr Isotope Determinations Nd and Sm isotopes were measured with a Finnigan 262 thermal ionization mass spectrometer (TIMS) at the University of Adelaide. Sample powder weight (grams) was calculated on the basis of a nominal 2 μg of Nd. Isotope dilution mass spectrometry was facilitated by the addition of a 150Nd/147Sm mixed spike. Most Sr and all Nd whole rock isotopic ratios were analysed in the same Adelaide laboratory on a Thermo- Finnigan MAT 262 thermal ionisation mass spectrometer, following procedures described by Elburg et al. (2003). The 143

Nd/144Nd La Jolla standard yielded a value in the range 0.511843 ± 9 (2 SD; n = 8) and 0.511827± 6 (2

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SD; n = 5) during the periods of analysis, and all analysed samples were normalised to a value of 0.511860 for this standard. Present-day ɛNd(t) values were obtained with CHUR values for 143Nd/144Nd (0.512638) and Sm/144Nd (0.1966) and depleted-mantle 143Nd/144Nd (0.513150) and 147Sm/144Nd (0.2145) ratios taken from

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147

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Goldstein et al. (1984). Depleted-mantle model ages (TDM) were calculated on the basis of these ratios.

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4.4 Whole-Rock Major- and Trace element Analysis

Samples were analysed using previously described XRF methods at the University of Adelaide (Foden et al.,

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5. Results

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2002a) and by multi acid digest and ICP-MS analysis at Amdel / Bureau Veritas laboratories in Adelaide.

5.1 Results of 40Ar/39Ar and U-Pb Zircon Dating Foden et al. (2006) summarised age constraints on the evolution of the Delamerian Orogen. In this paper we supplement this original data set with some new U-Pb LA-ICP-MS data from zircon and monazite (Table 3, Supplementary data Table S2 and Figures 4 and 5) and a 40Ar/39Ar determination on fabric defining metamorphic muscovite (Table 2; Fig. 3).

5.1.1 40Ar/39Ar: A sample was taken from the Harvey’s Return locality at the NW corner of Kangaroo Island (E–N). Here deformed amphibolite facies metasedimentary rocks of the Kanmantoo Group have been transported towards the Gawler Craton margin in the hanging wall of the major Kangaroo island thrust system, part of the

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Journal Pre-proof regional D1 structural event (Flöttmann et al., 1998). The inter-bedded sandstone-mudstone 1–20cm sedimentary layering of the Kanmantoo Group has been recrystallised to prominent black and white pelitepsamite layers with prominent chlorite-absent, biotite and muscovite growth implying a metamorphic temperature of ~550oC (e.g. Tinkham et al., 2001), and defining the axial planar foliation of the northvergent recumbent folds. Three muscovite samples were separated for 40Ar-39Ar analysis at Curtin University and yielded a weighted plateau age of 502.4 ± 4 Ma. (Fig. 3). As the metamorphic temperature of muscovite growth in these samples are probably ~200oC > the 40Ar-39Ar closure T for muscovite (350oC; Harrison et al.,

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2009), this is likely to be a cooling age. Even if a quite rapid cooling rate (20oC/m.yr) was assumed this implies that the age of tectonically imposed muscovite growth may have been 10m.y older than the cooling

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age, suggesting the age of thrusting to be ~512 Ma (regional D1).

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5.1.2 LA- ICP-MS zircon U-Pb dating:

Five samples of the post-tectonic A-type magmatic ‘Padthaway Ridge’ (Fig 4) series (Turner et al., 1992)

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were taken from scattered outcropping inliers in the Murray Basin. Details of these samples and results are

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summarised in table 3. The analysed samples are: the Mannum granite (1109-7), the Marcollat Granite (JF07-118), the Mt Monster rhyolite porphyry (JF07-108), the granite at Monteith (KW08-15) and the

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granite at Kongal Rocks (JF07-114b). These each yielded abundant zircons and using CL imagery showed well-defined magmatic concentric zonation. Concordia ages range between 486.1 ± 1 Ma (Kongal Rocks, JF07-114b) and 470.1 ± 1 Ma (Monteith Granite, KW08-15). Between these limits, the Mannum Granite has a 482.7 ± 2 Ma age, the Marcollat Granite a 478.2 ± 0.8 Ma age and the Mt Monster porphyry a 472.5 ± 1 Ma age (Fig 4). An undeformed granodiorite sample from drill hole PADD28 may also be a member of the Padthaway Ridge suite and has an age of 475.2 ± 1 Ma. (Fig. 4). These ages are all consistent with earlier data that suggest that convergent deformation of this part of the Delamerian Orogen ceased at about 490 Ma (Foden et al., 2006). A slightly foliated quartz diorite was sampled from the most southeasterly drill hole LD3, and yielded a concordia age of 516.1 ± 2 Ma. A granodiorite sample was also taken from hole PADD32 and this yield a lower intercept age of 513.4 ± 5.7 Ma. (Fig. 5)

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Journal Pre-proof As discussed below, in contrast to all other granites in the belt, the Kinchina Quarry near Murray Bridge exposes sills of medium grained granite with distinctive adakite-like characteristics. The observed open folding and weak foliation and may be interpreted as late syn-tectonic (D2). New LA-ICP-MS data reported here on magmatic monazite separates yields a precise 495.0 ± 1.2 Ma age (Fig. 5). This is within error the same as a prior TIMS monazite age (492.8±1.3 Ma; Foden et al., 2006). A sample of the Lalkaldarno Porphyry was also taken from the Mt Stavely Volcanic Complex. This is a shallowly intrusive dacite porphyry and is apparently the youngest unit in the Mt Stavely volcanic

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stratigraphy (Bowman et al., 2019) and yields a LA-ICP-MS U-Pb age on separated zircon of 504.7 ±2 Ma

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(Fig. 5). This is very consistent with recent SHRIMP data (Lewis et al., 2016).

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5.2 Whole-rock Geochemistry

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Based mostly on geochemistry, the transect of the Delamerian Orogen that includes South Australia and

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western Victoria hosts five distinctive mafic magmatic suites and at least five felsic suites that range in age

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from Early Cambrian through to Early Ordovician (Table 4, Supplementary Data Table S1).

5.2.1 Mafic rocks in exposed outcrop.

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Cambrian basalts and dolerites are exposed as outcrop in the southern part of the Adelaide Foldbelt (SAFB) in the Adelaide Hills and on Kangaroo Island as well as in the Glenelg and Stavely regions of western Victoria (Tables1, 4 & S1).

i) Alkali Basalts: In the Adelaide Hills the early Cambrian Normanville Group hosts basaltic lava flows of the Truro Volcanics (Foden et al., 2002a; Forbes et al., 1972) and mafic sills and dykes of tholeiitic composition intrude the late early Cambrian Kanmantoo Group. The Truro Volcanics (Fig 6) are highly alkaline, (originally) undersaturated basaltic lavas (Foden et al., 2002a). These are variably deformed, metamorphosed and altered. They mostly outcrop on the flanks of the Karinya syncline to the north and northeast of Adelaide near Dutton (328918N 6196408E) and at various places within the Normanville Group south of there (e.g. Red Creek). They are MgO-rich (>10%) and have high compatible element contents (Ni

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Journal Pre-proof 200–300 ppm; Cr 405–600 ppm) and have high Mg# (0.65) values all suggesting these are near-primary unfractionated melts. They have high TiO2 and very high Nb (~100 ppm) and high LREE as well as high Nb/Y and Ce/YN values (~10). They have high Nd(i) values in the range +5 - +7.8 close to the expected contemporary DMM values of +8 (Fig 19; Table 5).

ii) Tholeiites: Intruding the Kanmantoo Group, this suite occurs as dykes and sills (Fig. 6). Liu and Fleming (1990) observe that their relative intrusive ages range throughout the D1 to D3 deformation history recorded

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by the Kanmantoo Group. Members of this suite include the Woodside dykes in the Adelaide Hills, the Cape

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Hart dykes on Kangaroo Island, the mafic sills in the Monarto district and Kinchina quarry and mafic bodies in the Tanunda gneiss complex near the Barossa valley. These tholeiitic basalts (Fig 6) are moderately Mg-

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rich with between 6 and 9% MgO. Mg# values vary from ~0.65 down to ~0.45 in systematic covariation

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with other elements that imply some degree of fractional crystallisation (Fig 6). As pointed out by Liu and

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Fleming (1990) Al2O3 seems to show two different trends with respect to decreasing MgO, one of enrichment (up to 21% Al2O3) and the other depletion. The two trends converge at the most primitive high

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MgO samples with ~ 15.5% Al2O3. The most undifferentiated samples from this suite have > 100 ppm Ni, >400 ppm Cr and 30–35ppm Sc with quite low TiO2 (0.8–1%). These most mafic samples, which are close

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to unfractionated primary mantle melts, also have low LREE (Ce ~15ppm) and low Zr (~50ppm). Highly compatible elements such as Ni and Cr show strong positive correlation with Mg#. Significantly, with respect to decreasing Mg#, Sc shows a trend of initial enrichment then followed by depletion. Those incompatible elements that are less likely to be impacted by mobility during metamorphism and alteration (e.g. REE, TiO2, Zr, Nb, Th) all show negative correlation with Mg# implying control by fractional crystallisation. These samples have flat REE patterns (Fig 7) in the range 10–20x chondrite. The normalised incompatible element patterns are also flat and somewhat MORB-like but differing in their slight enrichment of LIL elements and some negative Nb and positive Pb anomalies. They have Ti/V ratios in the range 20–50 (Fig 10). Their Nd(i) values are mostly in the range +2.5 – +7 (Table 5; Fig. 19), although some have lower values (-2.5 -1) probably reflecting continental crustal contamination.

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Journal Pre-proof 5.2.2 Mafic rocks in Murray Basin drill core. Drill cores sampled for this project are listed in Table 1 and the composition of mafic samples is illustrated in Fig 6. Sampled mafic rocks from the Murray drill cores are dominantly volcanic but also include gabbros and dolerites. Included amongst these mafic Murray Basin samples are the gabbros, norites, monzogabbros and dolerites from Black Hill complex rocks sampled from North Broken Hill core (Turner and Foden, 1996; DDHs S1-S18). Samples range from strongly deformed with strong steep-dipping cleavage (eg. KTH012), to fresh undeformed, apparently post-tectonic lavas (e.g. holes WYN1, PADD28, PADD31, PADD32). As

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illustrated (Fig. 6) the geochemical composition of the Murray Basin suites overlap the values of the

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outcropping ABF group, but also extend to more diverse compositions. The Murray Basin mafic suites are plotted with the SAFB data in three discrimination diagrams (Fig. 9 , Zr/4-2Nb-Y; Meschede,1986; Fig. 9,

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La/10-Y/15-Nb/8; Cabanis and Lecolle, 1989; Fig. 8, TiO2 v Y/Nb; Floyd and Winchester, 1975). These

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show that there is significant overlap with the SAFB data and importantly repeatedly distinguish three

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contrasting REE patterns.

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discreet suites within the Murray Basin mafic sample group. These are also clearly differentiated by their

i) Alkali Basalts: As in the Adelaide Hills mafic suites, there is an alkaline volcanic suite sample in Murray

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Basin core (Tables 1 & 4). These lavas were sampled from drill holes; COP57, MTR10, COP55, PADD31, PADD33, PADD32, S10, KTH-011, KTH-005, Yumali3, Yumali 4, Yumali9. They are characterised by high to very high TiO2 (mostly > 2.0%) and high Nb contents with high Nb/Y ratios (Fig. 8). They are persistently identified as anorogenic or within-plate by all basalt discrimination diagrams. Their Ti/V ratios (50–100) are significantly higher than for all the other mafic suites (Fig. 10). Although they have similar compositions to the early Cambrian Truro Volcanics, these Murray Basin lavas are consistently undeformed and could be regarded as post-tectonic and therefore younger than termination of Delamerian deformation at 490 Ma (Foden et al., 2006). In this case these basalts are > 30my younger than the Truro suite and not equivalent. And yet Gibson et al. (2015) also recognise a similar but deformed alkaline mafic suite hosted by the Harvester’s Creek greywacke in the Glenelg terrane, which they equated with the Truro Volcanics. This may add some weight to an interpretation that although not deformed these drill core samples could have

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Journal Pre-proof simply evaded deformation due limited burial. This alkali basalt suite is characterised by steep LREE enriched, HREE-depleted patterns with La/YbN in the range 5 to 13 and Ce/YN in the range 3.5–10. They have Yb and Lu values < MORB at 2–4x primitive mantle values. On the primitive mantle normalised, incompatible element diagram (Fig. 7) this suite shows a smooth pattern from ~100x at Cs and Rb down to ~3x at Yb and Lu. There is little or no positive Pb anomaly and no negative Nb and only some slight suggestion of a negative Sr anomaly. They have initial Nd(500) values in the range +3 to +3.8 (Table 5).

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ii) Tholeiites: A second subgroup of samples from the cores (Tables 1 & 4) has similar compositions to

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outcropping tholeiites in the southern AFB. The suite is represented in several drill holes, (MTR12, COP56, WYN1, Yumali-1,-2,-5, KTH004, KTH003) and includes both deformed (MTR-12, COP56) and

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undeformed (WYN-1) members. The group has characteristically flat, MORB-like REE patterns (Fig. 7),

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very low Nb and low to moderate TiO2 (Fig. 6). Although sharing similar trends with the outcropping tholeiites in the SAFB these tend to be compositionally more variable extending over a wider range of Mg#

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values (Fig. 6). Like the AFB tholeiites they also have flat REE patterns with La/YbN = 0.5–1.5 and Ce/YN =

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1–2, but with lower total REE and lower Nb, Zr and Y (Fig. 7). As with the SAFB tholeiites their Ti/V values are in the 20–50 range (Fig. 10), though a bigger proportion of these samples tend to cluster to the low

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end of this range. As discussed later this contrast may imply a west to east depletion trend in the mantle source of this suite. The normalised incompatible element plots show that this group resembles MORB for REE, Y and HFSE, but has positive Pb anomalies as well as enrichment in Cs, Rb, Th, U and K. The deformed members of this group all have Nd(i) values in the +0.3-+0.6, while the undeformed tholeiites from WYN1 have significantly higher values (+5.8; Table 5).

iii) Sub Alkali mafic rocks: (Tables 4, S1) On a range of discrimination diagrams (Fig. 9 , Zr/4-2Nb-Y; Meschede ,1986; Fig. 9, La/10-Y/15-Nb/8; Cabanis and Lecolle, 1989; Fig. 8, TiO2 v Y/Nb; Floyd and Winchester, 1975) a third discrete Murray Basin mafic suite is also distinguished which falls between the alkaline and tholeiitic suites. This is defined by its moderately LREE-enriched REE pattern with La/YbN = 3–7 and Ce/YN = 2.5–6. The suite follows similar compatible element (Ni, Cr, Sc) trends to the tholeiites. On

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Journal Pre-proof the primitive mantle-normalised diagram this group contrasts with the alkaline series in having positive Pband negative Nb-anomalies. It also has positive Cs, Rb, Th, U and K-enrichments and a slight negative Ti anomaly. These sub-alkaline rocks comprise gabbros, norites, gabbro norites and monzogabbros from the Black Hill intrusion cores (drill cores S1-S18; Turner et al., 1996) as well as basalts and gabbros from drill holes KMD-07, Coonalpyn-1, -2, KTH004 and Yumali-6. Their Ti/V ratios (30–40) fall between those of the tholeiite and alkaline suites (Fig. 10). Samples assigned to this group have initial Nd values in the range +3 to -1.4 (Table 5). These sub-alkaline suite members are mostly located towards the western Margin of the

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Murray Basin and are best interpreted as more continentally contaminated tholeiites (Fig. 9).

iv) Boninite: Drill hole KTH-012, located towards the eastern border of South Australia, has fine grained

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volcanic rocks with a strong steeply dipping cleavage. These are andesitic in silica content (57.2-59.8%) with

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very high MgO (8.8–9.2%), high Mg# (0.7) and very low TiO2 (0.54%). They have very high Ni (200–300

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ppm), Cr (600–650 ppm) and Sc (35–30 ppm) (Fig. 11). They have high Al2O3/TiO2 (~25) and plot towards the higher SiO2 and lower Al2O3/TiO2 end of the global boninite sample range. They are most similar to the

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low-Ca (CaO/Al2O3 < 0.5) boninite series (Fig. 14; Crawford et al., 1989). They have low Ti/V close to 20 (Fig. 10). Their (slightly) concave upwards REE patterns resemble those of some modern boninites (Fig. 11)

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from the western Pacific (Tonga; Falloon et al., 2008) as do their normalised incompatible element patterns. This includes characteristic strong HFSE depletions inherited from a highly depleted, refractory mantle source, with significant enrichment of LREE and LILE elements. This re-enrichment of the mantle wedge is typically attributed to the addition of a subduction component (Falloon et al., 2008). As these high-Mg andesites have quite low initial Nd values in the range -5.2 to -5.6 (Table 5) and are more LREE-enriched than many boninites, their composition may reflect the role of a subduction component as well as some continental crustal contamination. The Magdala basalts (Table 4) that outcrop directly east of the Mt Stavely outcrops and immediately to the east of the Moyston Fault are significantly different to those described from the Stawell Mine further north and also referred to as Magdala basalt (Squire et al., 2006). While the latter are relatively Ti-rich tholeiites, these are boninite-like, very low TiO2 (0.18–0.34), high MgO (9–6.5%) basalts with high Ni (165–92 ppm)

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Journal Pre-proof and Cr (464–61 ppm) and extreme depletion in HFSE (Zr 6–21 ppm) and REE (< 1 ppm Nd) and moderate enrichment of LILE, features shared with the Mt Stavely lavas. They have very low Ti/V close to <10 (Fig. 10) placing them in the low-Ti arc tholeiite/ boninite field. They have high initial Nd values of +5.2 (Table 5; Fig. 19B).

5.2.3 Intermediate to Felsic Suites. There are five well defined, distinct suites of felsic to intermediate magmatic rocks. These comprise syn-

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tectonic to late syn-tectonic I- and S-type granites (e.g. Foden et al., 2006; Foden et al., 2002a), A-type

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granites (Padthaway Ridge), an adakite suite and the Mt Stavely andesite and dacite lavas and porphyries. The Murray Basin drilling has also intersected intrusions of undeformed, potassium rich granite that are

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clearly part of the Pathaway A-type granite suite (Holes S10, PADD32, KMD-07, PD1). In addition, other

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intermediate to felsic magmatic rocks are intersected in many of the drill holes (MTR12, MTR13, WYN1,

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KMD-07, PADD28, LD3, COP56, Coonalpyn-4). These include andesite and rhyolite lavas and diorite and

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quartz diorite intrusives. Many of these are deformed.

i) I- and S-type granites: These variably deformed intrusions outcrop in the Adelaide Foldbelt in the

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Adelaide Hills, on Kangaroo Island and northwards towards Broken Hill (Anabama granite; Foden et al., 2006; Foden et al., 2002a; Foden et al., 1999; Milnes et al., 1977; Sandiford et al., 1992). They have directly equivalent intrusions with similar ages in the Glenelg region in western Victoria (Gibson et al., 2015; Ireland et al., 2002; Kemp, 2003; Kemp et al., 2002). The I-type intrusions fall across the tonalite-granodiorite and granites fields on a normative Ab-AnOr diagram (Fig. 12) whereas the S-types are restricted to the granite field (Fig. 12). The I-type granitoids range from metaluminous diorite and granodiorite to weakly peraluminous granite (Fig. 13). On a SiO2MALI diagram (Frost et al., 2001) they are defined as calc-alkaline (Fig. 13). They have a wide range of Mg# values from ~0.6 down to 0.2 in contrast to the entirely peraluminous S-types which have a restricted range of Mg# values (mostly between 0.4 and 0.5). The more silica-poor I-types are relatively CaO- and Al2O3-rich, showing decline with decreasing Mg#, as do Cr, Ni and Sc. By contrast the S-types show a

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Journal Pre-proof restricted range of silica (~70–75%) and tend to have higher Mg# and higher Ni, Cr and Sc at similar silica levels to the I-types. The REE patterns (Fig 14) are similar with moderate LREE enrichment and slight negative Eu anomalies (S-types more than I-types). Their normalised incompatible trace element patterns show negative Nb, Sr, P and Ti anomalies and positive Pb anomalies (S-type >> I-type). The S-types are slightly more Ba-rich than the I-types. While most of the outcropping I- and S-type granites in the AFB are syn-tectonic, the Taratap Granite near Kingston in SE SA is a clearly post-tectonic S-type granite. Based on new (Table 5) and previously reported Nd isotope data (Foden et al., 2006; Foden et al., 2002a;

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Turner et al., 1993) the S-type granites closely overlap the Kanmantoo Group sedimentary rocks (ɛNd(500) -

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14 to -10; Haines et al., 2009; Turner et al., 1993) and their Nd values extend from -13.5 to -7.8. The I-type granitoids have more primitive isotopic compositions and range from -6.5 up to -2.5. Whereas the S-type

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granites show Nd isotopic variation at constant Sm/Nd (Fig. 19A ), showing apparent mixing variation

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between the I-type granite field and Kanmantoo sedimentary rocks, the I-types show some positive covariation of Sm/Nd with 143Nd/144Nd(I). This implies a linkage between the I-type granites and more mafic

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parental magmas with higher Sm/Nd and 143Nd/144Nd(I).

ii) A-type granites: These are post-tectonic (490–470 Ma) A-type granites forming the so-called Padthaway

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Ridge (Fig. 2; Turner et al., 1992). This is a prominent magnetic feature extending south eastwards over 500 km from the eastern Adelaide Hills to SW Victoria (Dergholm Granite). Although there are only scattered outcrops as inliers within Mesozoic to Cenozoic Murray Basin cover, this suite is by far the most voluminous of the Delamerian granite series in South Australia. Notably there is no direct equivalent of this magmatic suite in the Delamerian record in the Koonenberry area to the north or in Tasmania and the complex only extends into the western-most exposure of the Victorian Cambrian (the Dergholm Granite). However equivalent post-tectonic A-type granite intrusions are reported from the Ross Orogen in central Victoria Land (e.g. the 490±4 Ma Irizar Granite; Rocchi et al., 2009). These are relatively K2O-rich, silica-rich granites (Fig. 15D, Fig. 18) and are associated with contemporary mafic magmas (Turner and Foden, 1996; Turner et al., 1996). They fall in the alkali-calcic field on a SiO2-MALI diagram (Fig. 13) and are ‘ferroan’ (Frost et al., 2001). They show a wide range of Mg# values from ~0.45 down to < 0.1. Compatible trace

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Journal Pre-proof element values decline to very low values over this Mg# range. They have distinctive REE patterns (Fig. 15) tending to “gull wing” style (Bachmann and Bergantz, 2008) with high LREE and quite high and relatively flat MREE to HREE patterns and in some cases even have Gd(N)/Yb(N) < 1. They have very large negative Eu anomalies. Normalised incompatible element patterns have large negative Ba, Nb, Sr, P, and Ti anomalies and modest positive Pb peaks (Fig. 15). These granites have significantly higher initial Nd values than the I-type, mostly in the range -3 to +1. Again, there is slight positive covariation of Sm/Nd with Nd(i) (Fig. 19A). They are directly associated with

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co-magmatic mafic rocks of the sub-alkaline group discussed above group (Mannum, Monteith) described

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above. This direct relationship includes mafic dyking as well as mafic magma mingling (Turner and Foden, 1996). These co-magmatic mafic rocks have Nd(i) values that overlap the A-type granites, in the range -1.4

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to +1.8 (Table 5, Fig. 19A).

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iii) Adakite: Granitic rocks of adakite (Castillo, 2012) affinity are identified at a restricted locality in the eastern Adelaide Hills (Monarto/ Kinchina Quarry). These late syn-tectonic 495 ± 1.2 Ma (see below)

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granites occur as sill-like intrusions in Kanmantoo Group metasediments and are interleaved with tholeiitic dolerite sills. They are very different from the contemporary I- and S-type granites. They have granodiorite

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to granitic bulk compositions and on an An-Ab-Or modal/ normative diagram (Fig. 12) they straddle the trondhjemite–granite fields. They are mildly peraluminous (Fig. 13), are more Ca-poor and Na2O- and Al2O3-rich than the contemporary I- and S-types. They have distinctive highly fractionated REE patterns (Fig. 15) with strong HREE depletion (3–6x chondritic) and LREE enrichment (200–400x chondrite). They are very Y-depleted (<10 ppm), have no Eu anomalies and only weak negative Sr anomalies they have very high Ce/YN (60–100) and very high Sr/Y (> 40) and are very Ba-rich. They differ from the other I-, S- and A-type granites in having significantly higher initial Nd values (+1 to +3, Fig. 19, Table 5). These resemble the ‘high SiO2’ adakites (Castillo, 2012).

iv) Murray Basin intermediate to felsic Rocks. While many of the available drill cores intersect obvious members of the Padthaway Ridge A-type granite suite, some cored samples (WYN-1, MTR13, PADD28,

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Journal Pre-proof KTH1, LD3, M161, COP58) reveal a diverse range of intermediate to felsic rocks that include both volcanics and intrusives. These include both deformed and undeformed examples ranging from andesite to dacite (WYN1, COP56, Coonalpyn4, MTR13) and rhyolite (KTH1) as well as quartz diorite (LD3) and granite (M161). Their silica content ranges from 55 to 75% with a significant proportion in the range 55 to 65%. They are mostly metaluminous and on the SiO2 v MALI figure (Fig. 13) they plot as calc-alkalic. Some have low TiO2 declining with increased SiO2 , but there is also a relatively TiO2-rich sub-group with TiO2 in the range 1.7 to 2.2% (Fig. 17). These Ti-rich samples are undeformed with 58–65% SiO2 and in this study are

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predominantly from drill hole PADD28 (U-Pb on zircon age = 475.2 ± 1.4 Ma. Fig. 4, Table 3). The lower TiO2 samples also have high Al2O3 and prominent negative Nb and positive Pb anomalies. They have REE

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patterns which are very flat in the MREE to HREE range (average ~20x chondrite) and with modest LREE

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enrichment (La = 80–120x chondritic; Fig. 15) and slight negative Eu anomalies. On granite discrimination

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diagrams (Fig. 16) they straddle between VAG fields and WPG (the higher TiO2 sub-group). Excluding the more TiO2-rich samples, these intermediate to felsic samples are very comparable with modern subduction

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suites (Fig. 17). They include quartz diorite LD3 that which yielded a 516 ± 2 Ma U-Pb age (Fig. 5 , Table 3) and PADD32 with a U-Pb age of 513.4 ± 5.7 Ma . Most of both the deformed and undeformed members of

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this group have initial Nd values in the range (-0.4 to -3.0; Fig. 19; Table 5).

v) Mt Stavely andesite and dacite lavas: Most geochemical variations show that the outcropping Mt Stavely Volcanics share common characteristics and lie on the same trends as the very low Ti Magdala basalts from nearby to the east across the Moyston fault, implying that they belong to the same suite. The Mt Stavely outcrops are dominated by andesite and dacite lavas. They are all metaluminous and have very distinctive compositions with seeming high Mg andesite/ boninite affiliations. They are metaluminous and have high CaO, MgO, Ni, Cr, Sc and extremely low Ti, Zr, Nb. Many of the andesites and some dacites have Mg# > 0.6. Their REE patterns mostly have flat MREE to HREE at ~ 10x chondrite and they have weakly enriched LREE/MREE with little or no Eu-anomaly. As an exception to this the youngest unit in the Mt Stavely stratigraphy (the Larnakardo porphyry; Bowman et al., 2019) has a distinctive fractionated REE pattern (Fig. 15) with strongly depleted HREE and without Eu-anomaly) and is very like the Adelaide Hills

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Journal Pre-proof Kinchina adakite described previously. This boninite-adakite association has been described from several Neogene western Pacific subduction margins (Falloon et al., 2008; Li et al., 2013). As a group the Mt Stavely suite all show large negative Nb and Ti anomalies and strong relative enrichment of Pb, K and U. Rb, Ba, Th and U are enriched but with relative enrichment U>Th and Ba > Rb. Some show weak positive Sr anomalies (Fig. 15). These Mt Stavely Belt have initial Nd values in the range +2 to -4.4, though most are in the -3 to -4 range (Fig 19B; Table 5).

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6. Discussion

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6.1 Geochemical tectonic discrimination

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We have used several discrimination diagrams as a means of assessing the tectonic settings of the mafic members of the magmatic suites. For the mafic rocks, these are the TiO2 v Y/Nb diagram (Floyd and

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Winchester, 1975), the Zr/4-2Nb-Y diagram (Meschede, 1986), the La/10-Y/15-Nb/8 diagram (Cabanis and

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Lecolle, 1989) and the Ti /1000 v V diagram (Shervais, 1982). The effectiveness of the discriminations indicated by the fields defined in these diagrams has been tested using large modern data sets with well-

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established tectonic settings from GeoROC (Sarbas and Nohl, 2008). There are four geochemically distinctive mafic suites; i. alkali basalts, ii. MORB-like tholeiites, iii.

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transitional sub-alkali basalts and mafic intrusives and iv. boninite-like high Mg andesites. Although the alkali series includes the highly alkaline and deformed Truro volcanics which are early- or pre-Delamerian, these have some geochemical distinctions from the other alkaline lavas from Murray Basin drill core (Fig 6), which are undeformed, implying that they post-date the last Delamerian contraction at 490 Ma (Foden et al., 2006). The discrimination diagrams all classify this sample group as alkaline basalts from anorogenic or within plate settings. They clearly differ from syn-subduction magmas in having much higher TiO2, in lacking negative Nb anomalies and in having no prominent positive LIL and Pb anomalies. The discrimination diagrams all define the tholeiite samples as N- or E-MORB or as continental tholeiites or as back-arc basalts and as illustrated in figure 6, the least differentiated members of this group fall directly in the MORB field (Jenner and O'Neill, 2012). Dispersal out of this field results from a combination of fractional crystallisation (see trends in Fig. 6) and, as implied by Nd-isotope shifts towards

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Journal Pre-proof lower initial Nd(I) values, some continental crustal contamination (Fig. 19). This affiliation is also supported by geochemical variation trends within the suite. The Murray Basin tholeiites also share Ni- and Crdepletion trends with declining Mg# with the SAFB suites. And in both groups the inflected TiO2 and Sc trends of initial increase with declining Mg# followed by decline are consistent with initial olivine-spinelplagioclase controlled fractionation of parental mafic melts, followed later by saturation of clinopyroxene. This is the same low-pressure crystallisation behavior as MORB (Yaxley, 2000), emphasising the MORBlike character of this suite. This is consistent with decompressional melting of upwelling DMM

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asthenosphere during lithosphere extension. The Al2O3 variation implies early plagioclase saturation and

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hence implies relatively low initial H2O content. While Liu and Fleming (1990) proposed separate Al2O3defined suites, in reality the Al2O3-enrichment trend is at constant Mg# and must simply be due to

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plagioclase accumulation presumably due to flotation and sorting during in-dyke magma flow.

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As illustrated in Figs 9 and 10, reflecting its mixed (subduction and rift) origins, the geochemical identity of the back-arc basalt field is not uniquely defined by most discrimination diagrams but it

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consistently falls between the MORB and Island Arc basalt field. On the Ti/1000 v V diagram (Fig 10) and

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on both the Zr/4-2Nb-Y and the La/10-Y/15-Nb/8 diagrams (Fig 9) all the Delamerian mafic suites fall in the same broad fields as modern back arc basalts, though in detail there are subtle variations. In the Zr/4-2Nb-Y

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diagram the sub-alkalic mafic rocks tend to skew more into volcanic arc basalt field ‘C’ than the BAB series. Likewise in the La/10-Y/15-Nb/8 diagram this series trends slightly into the ‘calc-alkali’ field (from the BAB-continental basalt field), suggesting that this series are more subduction-like than the other two series, though this probably reflects continental crustal contamination as indicated (Fig 9). Crustal contamination in the sub-alkalic series is also consistent with the prominent positive Pb and negative Nb anomalies and the fact that on the Ti/1000 v V diagram (Fig. 10) this series is less arc-like than the tholeiite series and lie between the tholeiites and the alkaline basalts. On this diagram the modern BAB suites closely overlap the field defined by the tholeiites and even plot a little further across into the designated ‘arc-tholeiite’ field (Tetley et al., 2019). Reflecting its slightly lower TiO2 and Nb, the least fractionated of the tholeiites from the Murray drill holes are displaced more towards the N-MORB- volcanic arc tholeiite fields in the Ti/1000 v V diagram (Fig 10) as well as the Zr/4-2Nb-Y and the La/10-Y/15-Nb/8 diagrams. This potentially reflects

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Journal Pre-proof derivation from a more depleted mantle source that may be developed in the approach to the then subduction plate boundary further east. The South Australian Cambro-Ordovician granites reinforce the tectonic setting conclusions from the mafic rocks. On standard granite discrimination diagrams (Pearce et al., 1984), the I- and S-type granites straddle the boundary between within plate (WPG) and volcanic arc granite (VAG) fields while the A-types plot mostly in the WPG fields. By contrast the Mt Stavely andesites and dacites lie well within the VAG fields (Fig.16). The intermediate to felsic samples from the Murray drill core include both those that fall into

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the VAG fields and some that are designated WPG. A core conclusion from the mafic rock geochemistry is that apart from the boninitic high Mg

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andesites, the SA mafic rocks are not produced directly in a subduction, volcanic arc setting. They are more

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likely to be rift-related and are like modern back-arc suites, particularly those where extended and thinned

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continental crust is present. Similarly, as supported by isotope-based constraints discussed below, and with the exception of the adakites, the I- and S-type granites not strictly ‘orogenic’ but result from thermal and

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material interaction between the rift-related mantle melts and the sedimentary back-arc basin fill (Kanmantoo

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Group).

Note that the NSW Mt Wright, the western Victorian Mt Stavely and the Tasmanian Mt Read Volcanics all

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occur within the same time interval (510–500 Ma) and are each classified by a wide range of discrimination diagrams as volcanic arc suites. They each have systematically lower TiO2 than most of the SA suites.

6.2 Tectonic controls on petrogenesis

Nd v 147Sm/144Nd show positively correlated trends (Fig 19) between the both I- and A-type granite fields and the mafic samples from the SAFB and the mafic to felsic samples from the Murray drill core. The linkage to the I-type suite requires a steeper trend than that to the A-types. These radiating trends converge on contemporary MORB (with an Nd at 500 Ma close to +8). The samples also define a general trend of negative correlation between SiO2 content and initial Nd. Together these relations strongly support coupled assimilation of continental material together with fractional crystallisation (AFC; DePaolo, 1981; Powell, 1984). In addition to the critical elemental melt –bulk mineral assemblage distribution coefficients (D

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Journal Pre-proof values), the geochemical impact of this process is also controlled by the ratio of the rate of assimilation by the magma (of crust) to its rate of crystallisation. This is described as the ‘r’ factor in governing equations (DePaolo, 1981; Powell, 1984). Taking the crustal assimilant as mean Kanmantoo Group shale and the mafic endmember as contemporary MORB, an r-factor of 0.35 models syn-tectonic I-type granite generation (Fig. 19). In the post-tectonic stage (<490 Ma) the same MORB source and crustal assimilant can produce the Atype granites but with less crustal assimilation and greater influence of fractional crystallisation (r = 0.15). As discussed below, we interpret that this major decline in crustal assimilation followed the delamination of

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dense, mafic underplate from the lowermost crust and transition to persistent lithospheric extension. In addition to the clear field evidence for mafic and granitic magma mingling (Turner and Foden,

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1996) linkage of the A- and I-type granites to contemporary mafic mantle input of MORB-like tholeiite

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composition is also supported by other element variation. This is in contrast for the model for the Ross

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orogen A-types where re-melting of parental lamprophyre is proposed (Rocchi et al, 2009). As illustrated in Fig 18, the tholeiite suite mafic rocks (which as already discussed are MORB-like) have elemental variation

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trends that link them to the A-type granites by fractional crystallization dominated paths. The tholeiite suites

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show reversals in trends of enrichment of both TiO2 and Zn as a function of declining Mg# marking the onset of Fe-Ti oxide. The alkali basalt suite by contrast has consistently high TiO2 and Zn (Fig. 18). This

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linkage between the A- type granites and a specifically tholeiitic mafic parent magma is also emphasised by the flat MREE-HREE patterns of these granites and the tholeiites (Dy/Yb of both the A-type granites and tholeiites have the same average Dy/Yb = 1.7 whereas the alkali basalts average Dy/Yb = 2.5; Figs 7, and 15).

As indicated in Fig 19A there is a continuous trend of initial Nd variation between the S- and I-type granites at constant essentially crustal Sm/Nd this is best interpreted to reflect direct mixing of Kanmantoo sediment melts with intruding I-type magmas. This is illustrated by field evidence that the Kanmantoo migmatite complexes which generate direct melts of the Kanmantoo complex are the sites of intrusion by and mingling with granite magmas of more I-type character (Foden et al., 2002a; Schwindinger and Weinberg, 2017).

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Journal Pre-proof Although there is a significant population of Nd v Sm/Nd trends that converge on contemporary MORB source (Fig. 19), there is also evidence of trends that do not project to contemporary MORB and must reach MORB-like initial Nd values at much higher Sm/Nd ratios (Fig. 19B). The KTH-012 boninites and the Mt Stavely Belt intermediate to felsic volcanics have quite negative initial Nd values (+2 to -6) but lie on potential trends (together with some of the deformed Murray Basin samples from cores) that suggest projection towards the Stavely Magdala boninite / low Ti tholeiites. These have initial Nd values of +5, but have far lower REE contents (< 1 ppm Nd cf 9 ppm Nd) and higher Sm/Nd ratios (0.434 cf 0.343) than

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MORB. Samples on these trends have low to very low HFSE contents and very high compatible element

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contents even in relatively silica-rich samples, suggesting they only have experienced limited fractional crystallisation. If these trends are treated as AFC trends (Fig 19B inset) regarding the Magdala low-Ti basalt

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as a parent, then they require implausible solutions. If regarded as AFC to achieve their Nd and 147Sm/144Nd

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values the trends require substantial fractionation and with miniscule rates (Fig 19B) of crustal assimilation

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(r = 0.007 to 0.005). This process would produce very low MgO, Mg#, Ni, Cr and Sc values that are completely unlike those of the samples. The more credible solution is that these are boninitic melts of

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refractory, highly depleted mantle that has been enriched with a component (2–4%) derived from subducted sediment. In this case their high SiO2 contents are closer to primary values, reflecting very low pressure,

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water-rich mantle melting (Falloon et al., 2008). As reflected by their high Mg# and Ni, Cr and Sc values they must have undergone only limited fractionation. We would interpret the generation of this depleted mantle to result from early (from ~520 Ma) tholeiitic melt extraction from an evolving mantle wedge above the newly foundering slab (Whattam and Stern, 2011).

6.3 The Delamerian subduction history This study provides geochemical, temporal and spatial constrains that show how this part of the Gondwananpalaeo-Pacific margin evolved and responded to the transition from passive margin to subduction. The 300 km wide transect of the Delamerian Orogen from its western edge at the eastern margin of the exposed Gawler Craton to the Mt Stavely Belt and Stawell Zone in western Victoria contains a 50m.y magmatic record extending from 522 Ma to 470 Ma. At 516.2 ± 1.5 Ma the quartz diorite from drill hole LD3 is the

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Journal Pre-proof oldest credibly subduction-generated magmatic rock in the belt and suggests subduction may have started as early as ~520 Ma. This requires that subduction was at least partly coeval with the deposition of the Kanmantoo group. Our results show that towards the developing South Australian foreland margin at the far western edge of the Delamerian orogen during the time interval from 522 to ~515 Ma, mafic magmatism underwent transition from alkaline to tholeiitic. Based on mafic rock geochemistry, the clear conclusion is that none of the three main defined South Australian mafic suites have subduction signatures. The tholeiites (suite#2) are MORB-like basalts, probably contaminated by continental crust. Their formation is consistent

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with production by decompressional polybaric melting associated with asthenospheric upwelling into a rifting and extended continental margin. The concept that the alkaline Truro suite are the product of smaller

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fraction, presumably higher pressure melt extraction is supported by their initial Nd values (up to +7.5)

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approaching those of the contemporary DMM and the Kanmantoo tholeiites and thus not requiring a distinct

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enriched mantle source. The tholeiites in particular correlate well with back arc basalt (BAB) characteristics and must be generated inboard of any volcanic arc. The alkali basalts (suite#1) that appear first at the earliest

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stages of back arc rifting have persistent ‘within plate’ designation and again have no subduction affiliation.

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Several recent studies (Leng et al., 2012; Stern et al., 2012; Whattam and Stern, 2011) have recognised that spontaneous subduction initiation is recorded by many supra-subduction ophiolites with

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numerous Tethyan examples. These record a magmatic sequence whereby early tholeiite (often with low and decreasing Ti) is intruded into what quickly becomes the back-arc. This is followed by boninite and calc alkaline suites. Prior to the establishment of down-dip subduction of the oceanic lithosphere, the first stage of oceanic lithosphere failure produces tholeiites due to asthenosphere upwelling into the developing mantle wedge above the foundering slab. The highly depleted mantle formed by melt extraction at this early stage creates the proto- mantle wedge and is then only further melted when down-dip slab motion commences and introduces subduction components including water. This stage may then produce boninite melts followed by arc tholeiites or calc-alkaline series magmas. This early stage of spontaneous subduction produces oceanward retreat of the trench with associated extension of the upper plate. This produces an extending back-arc basin with signature BAB tholeiite magmas and a zone of highly depleted mantle in the mantle wedge towards the forearc producing boninite related magmas. This model is directly applicable to the South Australian–western Victorian Delamerian.

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Journal Pre-proof Relative to the persistently MORB-like back arc basalts in the exposed Kanmantoo group to the west, the occurrence further east of high-Mg andesite boninite in drill hole KTH12, of boninitic basalt, andesite and dacite at Mt Stavely and in the Stawell Zone (Magdala Basalt) and of boninitic hornblende diorite in the Glenelg terrane is telling. Together with the eastward shift in the tholeiite chemistry towards more HFSE depletion and lower REEs (Figs 7 and 10), these factors all imply a progressive eastward transition towards a depleted mantle wedge resulting from initial slab foundering and eastward roll-back. The 516 ± 2 Ma quartz diorites in the LD3 hole are the most south-easterly Murray Basin samples taken in SA

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and together with the nearby highly deformed KTH12 boninite are the earliest and most westerly identified subduction magmatic activity in the belt. These samples are ~80 km east of the Glenelg terrane with its syn-

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D2 to post tectonic (<495±8 Ma; Ireland et al., 2002; Kemp, 2003) boninite intrusion as well as calc-alkalic

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basalts and VAG granites (Gray et al., 2002; Kemp, 2003; Kemp et al., 2002) and 150 km east of the

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boninitic 510–500 Ma Mt Stavely Arc. This implies initiation of subduction perhaps as early as 520 Ma followed by ~150 km of eastwards slab rollback in 10my to take the trench to the east of the Stavely arc by

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~510 Ma. Note that the implications of eastwards migration, coupled to the clear observation of direct

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intrusion of Kanmantoo equivalent sediments by boninite in the Glenelg Terrane all point to westward subduction and eastward slab roll back in this sector of the Gondwanan margin. This is similar to the

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conclusion of Johnson et al. (2016) with respect to the Koonenberry Belt. Cambrian boninite complexes are also described at other localities along the Gondwanan–Pacific margin. They occur in Tasmania with magmatic ages of 516–510 Ma based on specific dating of comagmatic gabbros and tonalites (Crawford and Berry, 1992; Turner et al., 1998; Mortensen et al., 2015). They also occur in the Ross Orogen in northern Victoria Land along the Lanterman-Mariner fault. This marks the east palaeo-Pacific margin of the Wilson Terrane craton, at its contact with the Cambrian Bowers Terrane (Palmeri et al., 2012; Tribuzio et al., 2008; Niagara Icefalls, Dessent Ridge and Mountaineer Range). In the north of the South Island of New Zealand they also occur in the Takaka Terrane (Münker and Crawford, 2000) at the base of the Devil River volcanic arc complex and have 516-514 Ma ages. In each case boninite magmatism marks a stage of subduction initiation at the Gondwana–Pacific margin. As also suggested by Kemp (2003), the model implied by our data for the SA–Victoria sector of this margin suggests west-dipping subduction with boninite and early calc alkaline magmatism and the

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Journal Pre-proof synchronous, early development of an extending back arc basin, and is the same as that proposed for the Koonenberry (Johnson et al., 2016). It is similar to models for the Northern Victoria Land margin (Palmeri et al., 2012; Tribuzio et al., 2008). It is also identical to the sequence proposed for the Takaka terrane in New Zealand (Münker and Crawford, 2000). It should be noted that the orientation of Cambrian subduction beneath the Australian sector of the Gondwanan margin has been controversial. Based on the assumption that the Tasmanian boninite complexes were generated in an offshore oceanic arc in the palaeo Pacific margin and obducted westward on to the

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Rocky Cape continental margin which was part of the downgoing plate, this model implies a phase of eastward subduction (Crawford and Berry, 1992). This may be consistent with the observation that Tasmania

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had a post Rodinina history that was separate from the Australian Gondwanan margin. Cayley (2011) and

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Moore et al. (2016) have postulated for a Tasmania that and which may be been first accreted to the

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Gondwanan continental margin between northern Victoria Land and Australia late in the early Cambrian

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6.4 Timing of deformation

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(Cayley, 2011).

The timing and cause of the Delamerian deformation (s) is a major issue. Johnson et al. (2016) assumed that

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the deformation in the Koonenberry Belt was entirely late (~500Ma) following a history of mid to late Cambrian subduction and back arc extension. In the South Australian transect we have concluded that there was also a history of on-going back-arc (Kanmantoo Basin) extension from the time of the early Cambrian extrusion of the Truro volcanics at 522 Ma onward through the Cambrian and into the clearly post-tectonic extensional phase after 490 Ma. And yet there is evidence that during this 522 Ma to 490 Ma interval, at least in the southern AFB, there were three distinct convergent deformation phases (Alias et al., 2002; Offler and Fleming, 1968) commencing with a major craton-ward D1 fold-thrust event (Flöttmann et al., 1998). The 40

Ar-39Ar age of 502.4 ± 4 Ma of S1 fabric forming muscovite published here (Fig. 3) is the only dating of

this D1 event. This is likely to be a cooling age. As the maximum metamorphic temperature of the Harvey’s Return meta-Kanmantoo sequence (and the dated muscovite) is likely to be between 500 and 550oC (chlorite-absent biotite-muscovite metapelite) the dated muscovite therefore probably grew at ~200oC > its

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Journal Pre-proof 40

Ar-39Ar closure T (350oC, Harrison et al., 2009). Even at a rapid cooling rate (20oC/ Ma) this implies that

the age of tectonically imposed muscovite growth may have been 10 Ma older than the cooling age, suggesting the age of thrusting (regional D1) could be ~512 Ma or older. Alias et al. (2002) have documented the sequence of magmatic intrusion, deformation and metamorphism at Petrel Cove adjacent to the Pt Elliot -Victor Harbor granite, demonstrating early (perhaps pre or syn D1) intrusion of mafic tholeiite and pegmatite and show that the 508± 2 Ma (Keeman et al., In submission), post-D1 Pt Elliot-Victor Harbor S-type granite intruded during or late in the D2 event and clearly cuts D1 foliation. This relationship clearly

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provides a minimum age for the D1 event (>508 Ma). And then the 495 ± 1 Ma Kinchina adakite and the 492.6 ± 1 Ma Reedy Creek granodiorite each also have tectonic fabrics which would logically be D3.

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These events seem to have equivalence in the Glenelg Terrane, where a 514 ± 6 Ma quartz porphyry

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intrusion is synchronous with or closely post-dates a D1 fabric, while a D2 event is recognised between the

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493 ± 8 Ma Wando Tonalite and the 490 ± 6 Ma Wando granodiorite (Gibson et al., 2015). The clearly

Lewis et al., 2016, Table 3).

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subduction related and weakly deformed Mt Stavely volcanics have ages between 510 and 503 Ma (Fig. 5;

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The cause of Delamerian deformation in the SA–Victoria sector of the plate margin remains unresolved. There is no clear evidence for accretion of exotic continental blocks at this time, though it has

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been suggested that the Rodinian elements of Tasmania (the Rocky Cape and Tyennan blocks) may have docked with the Gondwanan margin in the Cambrian (Caley, 2011). Gibson et al. (2015) have also suggested that the Mt Stavely belt may represent a colliding, boninitic oceanic arc, as discussed in this paper and by Kemp (2003) it seems clear that the boninites are generated from mantle beneath the Australian, and necessarily upper plate margin. The implication then is for orogenesis without collision, a process well recognised in the subsequent later Phanerozoic history of the Gondwanan Pacific margin (Cawood et al., 2011). As discussed by Greenfield et al. (2011) the current Pacific margin at the North Island of New Zealand may provide a good analogy. There Pacific-ward retreat of the Hikurangi Trench induces upper plate extension in the Taupo Volcanic zone, while at the same time periodic coupling between the upper plate and the down-dip motion of the subducting slab leads to simultaneous convergent deformation in the Axial ranges towards the forearc (Wallace et al., 2004). In this case convergence is driven by a combination of ridge push and slab pull forces.

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6.5 The termination of the Delamerian orogeny. As argued by Foden et al. (2006), South Australia Delamerian orogenesis associated with convergent deformation ceased at ~490 ± 5 Ma. Similar timing for Delamerian cessation is recorded from the Koonenberry Belt, the Mt Stavely Belt, the Glenelg Terrane and in Tasmania. In South Australia cessation of convergent orogenesis was followed by a period of bimodal anorogenic magmatism, dominated by A-type granites (Fig. 4; Turner et al., 1992). This phase continued for a period of about 20 Ma until ~470 Ma.

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In the Koonenberry Belt the Delamerian unconformity is overlain by the latest Cambrian or earliest

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Ordovician Kayrunnera Group sediments (Johnson et al., 2016). In the Mt Stavely Belt the 510–502 Ma volcanic terrane (Lewis et al., 2016) is cut by the post-tectonic 498 Ma Bushy Creek granodiorite (Whelan et

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al., 2007). Termination of deformation in the Glenelg Terrane is constrained to be between the 493 ± 8 Ma

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syn-D2 Wando Tonalite and the post kinematic 491±8 Ma Loftus Creek Granodiorite (Ireland et al., 2002;

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Morand and Fanning, 2006). In Tasmania the syn- to late- kinematic 510–493 Ma Mt Read Volcanics and Tyndal Group (Mortensen et al., 2015; Perkins and Walshe, 1993) are unconformably overlain by the post-

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Delamerian, latest Cambrian to Earliest Ordovician molassic conglomerates of the Dennison Supergroup (Jukes and Owen Conglomerates; Noll and Hall, 2003). This age of termination of the Delamerian also

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extends to the eastern end of the Ross Orogen in Northern Victoria Land with undeformed Granite Harbour granites having ages in the 504–485 Ma range and Ar-Ar hornblende and muscovite cooling ages in the range 488–482 Ma (Goodge and Dallmeyer, 1996). There is also good evidence that termination of convergent deformation `was followed by very rapid uplift and cooling. In Northern Victoria Land, Goodge and Dallmeyer (1996) estimate cooling at 30oC/ Ma and uplift at 1.2 km/ Ma. In South Australia, the (Figs. 2 & 4, Table 3 ) the erupted 472.5 ± 1 Ma Mt Monster rhyolite (part of the Padthaway Ridge A-type suite) unconformably overlies the by then exhumed to the surface Kanmantoo Group folded metamorphic complexes, whose pressures are estimated elsewhere in the belt to be ~3kbar (Alias et al., 2002). This implies erosion of at least 10 km of crust since the orogenic termination at 490 ± 5 Ma. 40Ar-39Ar dating of detrital micas from Ordovician turbidites in western Victoria (Turner et al., 1996) also demonstrate a detrital source from a rapidly exhumed Delamerian Orogen. Given

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Journal Pre-proof that post-Delamerian exhumation is not driven by convergent crustal shortening and vertical thickening, it must be buoyancy controlled and implies delamination of dense material from the Moho or below. It is also probable that subduction was terminated by slab breakoff and re-establishment further outboard (e.g. beneath the Ordovician Macquarie Arc in central western NSW). Percival and Pysklywec (2007), have discussed the occurrence of bursts of intrusion of post-orogenic granites lasting 20–40 Ma on several Archaean Cratons (Superior, Yilgarn, Slave) and have modeled these as the result of delamination of dense eclogitic metabasic rocks from Moho depths creating convective stirring

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of the lithospheric mantle. This results in partial localised overturn of the lithospheric mantle intruding a pulse of upwelling asthenosphere to near Moho depths. They predict this may decompress mantle material

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with T>1000oC to near Moho depths for > 10m.yr. This decompression will potentially generate both alkali

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and tholeiitic mafic partial melts dependent on percentage partial melting and depth of melt extraction. This

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would explain the occurrence of the post-tectonic tholeiite (suite#2) and alkali (suite#1) magmas. The predicted duration and physical characteristics of this process fit the petrogenetic requirements to generate

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the post-Delamerian A-type granites closely. In addition to their association with rapid post convergent exhumation and erosion, characteristics of the A-type suite that are compatible with this model include; high

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temperatures (950-1000oC; Turner et al., 1992) and their shift to an increased contribution of a mantle

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component as predicted by the ACF modeling.

Additional support for delamination is provided by the 495 ± 1.2 Ma. Kinchina adakite. As Percival and Pysklywec (2007) model predicts the dense delaminated eclogite (garnet pyroxenite) will produce silicic partial melts as the foundering down-flow is heated to >1000oC. The composition of the Kinchina adakite with its strongly fractionated and HREE-depleted, Eu-anomaly-free REE patterns, low Y and high Sr /Y ratios point to evolution in equilibrium with residual garnet and in the absence of plagioclase (Castillo, 2006) . Its high initial Nd values compared to the syn-tectonic granites also point to a mafic source. Experimental studies show that partial melting of mafic rocks sources at pressures between 1.4 and 3 GPa are in equilibrium with eclogite or garnet pyroxenite composed of residual garnet and clinopyroxene + rutile ± amphibole assemblages and yield melts with SiO2 in the range 58–72% (Pertermann and Hirschmann, 2003; Yaxley, 2000) at between 900 and 1050oC. Although extended petrogenetic discussion is beyond the scope of this paper, MELTS modeling (~2GPa, 1050oC) and trace element partial melting calculations using the

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Journal Pre-proof composition of the slightly crustally contaminated mafic tholeiite sills interleaved with the adakites in outcrop yield very close match to these adakites at ~20% melting. These melts are formed in equilibrium with a CPX-Garnet-Amphibole-Rutile residue.

7. Conclusions Figure 20 illustrates the model presented here for magmatic evolution in the Cambrian Gondwanan margin r in SE Australia. This study documents the magmatic consequences of the initiation of subduction at the South Australian- western Victorian sector of the Pacific – Gondwana margin. The resultant Delamerian

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Orogen in this sector is 300 km wide and hosts a magmatic history from the early Cambrian until the early

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Ordovician (522–470 Ma.). Our data shows that this 50 Ma syn- to post-Delamerian history started with commencing west directed subduction as least as early as 516 Ma. This was marked by volcanic arc-type

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andesite and quartz diorite (516.1 ± 2 Ma. Fig. 5) sampled from drill core from beneath younger sedimentary

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cover in the eastern Murray Basin. The occurrence nearby of likely forearc magmas in the form of highly

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cleaved boninitic high Mg andesite from drill hole KTH12 suggest that the volcanic arc was within easternmost SA at this early stage. From then on, Pacific-ward trench retreat resulted in volcanic arc

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migration to reach the Mt Stavely Belt and Stawell Zones in western Victoria by 510 Ma where boninitic arc magmatism continued until ~490 Ma (Kemp, 2003).

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Further west to the orogen’s foreland margin exposed in the AFB, early (522± 4 Ma) alkali basalt gave way to intrusion and extrusion of MORB-like tholeiite of back-arc basalt character, and through most of the middle and late Cambrian all of the South Australian Delamerian was in the back-arc and mostly under extension. Nevertheless there were two or three interludes of compression, the first being the major foreland fold-thrust D1 event in the middle Cambrian and the last at around 490 Ma. These compressive interludes resulted from periodic Pacific-Australian plate coupling beneath the forearc in western Victoria. In SA and the Victorian Glenelg Terrane the syn-tectonic I- and S-type granites all reflect back-arc mantle-derived magma and heat transport into the base of the Kanmantoo basin. This promoted partial melting and assimilation. They are essentially ‘rift granites’ and in addition to the key role of mantle-derived tholeiitic magma, their production was critically dependent on the very fertile, wet, recently deposited, Kanmantoo Group basin fill. Particularly in the South Australian back-arc zone, termination of the

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Journal Pre-proof Delamerian orogenic history at ~490 Ma was accompanied by buoyancy-controlled, uplift, exhumation and erosion. This was driven by delamination of a dense, Moho depth crustal mafic underplate whose re-melting at 1.5 to 2GPa and 950–1050oC generated the unique 495 ± 1 Ma AFB Kinchina/Monarto adakite. Slab rollback and breakoff is also likely, leading to re establishement of subduction further outboard (Macquarie Arc, NSW). This scenario is very like that proposed in the Ross Orogen (Rocchi et al., 2009). Delamination resulted in lithospheric mantle thinning and local convective overturn allowing shallow upwelling of the asthenosphere to drive the post-kinematic magmatic phase of the Delamerian, yielding voluminous 490Ma–

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470 Ma A-type granites accompanied by both post-tectonic MORB-like and alkali basaltic magmatism recorded in Murray basin cores samples. It is probable that the Padthaway Ridge defines the locus of

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asthenospheric upwelling produced by delamination. The results suggest significant similarities of events in

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this sector to those in the Koonenberry belt in western NSW (Greenfield et al., 2011; Johnson et al., 2016).

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8. Acknowledgements

This work was supported by an Australian Research Council (ARC) grant (DP0773913) to J.F. and M.E.

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David Bruce and John Stanley provided laboratory assistance. Fred Jourdan is thanked for assistance with Ar-Ar determinations. The work benefited from discussions with colleagues including Peter Haines, Ros Cayley, David Taylor, John Greenfield, Stacey Curtis, Anthony Reid and Mike Sandiford. Peter Rolley and

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9. References

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Hillgrove Resources are thanked for their recent assistance.

Alias, G., Sandiford, M., Hand, M., Worley, B., 2002. The P–T record of synchronous magmatism, metamorphism and deformation at Petrel Cove, southern Adelaide Fold Belt. Journal of Metamorphic Geology 20, 351-363. Bachmann, O., Bergantz, G.W., 2008. Rhyolites and their source mushes across tectonic settings. Journal of Petrology 49, 2277-2285. Berry, R., Chmielowski, R., Steele, D., Meffre, S., 2007. Chemical U–Th–Pb monazite dating of the Cambrian Tyennan Orogeny, Tasmania. Australian Journal of Earth Sciences 54, 757-771. Betts, M.J., Paterson, J.R., Jacquet, S.M., Andrew, A.S., Hall, P.A., Jago, J.B., Jagodzinski, E.A., Preiss, W.V., Crowley, J.L., Brougham, T., 2018. Early Cambrian chronostratigraphy and geochronology of South Australia. Earth-Science Reviews 185, 498-543. Black, L., 2006. SHRIMP U–Pb zircon ages obtained during 2005/06 for NSW Geological Survey projects. Geological Survey of New South Wales, Report GS2006/821. Black, L., 2007. SHRIMP U–Pb zircon ages obtained during 2006/07 for NSW Geological Survey projects. Geological Survey of New South Wales, Report GS2007/298. Boger, S., Miller, J.M., 2004. Terminal suturing of Gondwana and the onset of the Ross–Delamerian Orogeny: the cause and effect of an Early Cambrian reconfiguration of plate motions. Earth and Planetary Science Letters 219, 35-48. Bowman, N., van Otterloo, J., Cairns, C., Taylor, D., Cas, R., 2019. Complex evolution of volcanic arcs: The lithofacies and palaeogeography of the Cambrian Stavely Arc, Delamerian Fold Belt, Western Victoria. Journal of Volcanology and Geothermal Research 373, 120-132.

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Figure Captions. Figure 1 Regional map of Delamerian Orogen in South Australia and Western Victoria. Adapted from Miller et al. (2005). Figure 2 A.Total Magnetic Intensity (TMI) image of the Delamerian Orogen extending from Tasmania to western New South Wales. B. Detail of the Delamerian transect across southern South Australia into western Victoria

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showing the sampled Murray Basin drill cores and the Padthaway Ridge. Figure 3

Ar/39Ar analysis of muscovite separate from middle amphibolite facies metapelite of the Kanmantoo Group

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from the Harvey’s Return locality at the NW coast of Kangaroo Island. Muscovite defines axial planar S1

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fabric growth associated with recumbent folding and craton-ward thrusting. Figure 4

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Wetherill 206Pb/238U v 207Pb/235U Concordia plots of LA ICP MS analyses of zircons from the Padthaway

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Ridge A-type granite samples from Murray Basin drill core samples and outcrops. Figure 5

Wetherill 206Pb/238U v 207Pb/235U Concordia plots.

a.Monazite analyses from the Kinchina-Monarto

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adakitic granite, b. Zircon analyses from quartz diorite intrusion, drill hole LD3 from SE South Australian Murray Basin, c. Granodiorite intrusion from drill hole PADD32, d. Zircon analyses from the Mt Stavely

Figure 6

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Volcancics, Larnakardo porphyry (Bowman et al., 2019).

(A) TiO2 v MgO, (B) Al2O3 v MgO, (C) Zrppm v MgO and (D) Log Nbppm v MgO analyses of South Australian Delamerian basic magmatic rocks (SiO2 <55%). Red triangles – samples from outcrop in the exposed part of the orogen (the Adelaide Foldbelt – AFB), dark blue circles are samples from Murray Basin drill core to the east of the exposed AFB samples. Dark shaded envelope are the 522 Ma alkali Truro basalts sampled (Foden et al., 2002a), pale shaded envelope are the alkali suite samples from the Murray Basin drill core. MORB field are analyses of the global MORB glass samples (Jenner and O'Neill, 2012). The arrows show the trends for 50% fractional crystallisation for parent melts from three different primary MORB parents. Figure 7 Chondrite normalized rare earth and normalized incompatible element diagrams for Delamerian mafic rocks ; A) Tholeiites, closed circles from AFB outcrop, open circles from Murray Basin drill core, C) sub alkali basalts from Murray Basin drill core(including Black Hill intrusion; Turner et al., 1996), E) Murray Basin drill core alkali basalts.

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Delamerian mafic rocks plotted on the TiO2 v Y/Nb discrimination diagram (Floyd and Winchester,

1975) . Truro Volcanics - filled red circles , alkali suite from Murray Basin drill core - open inverted triangles, sub-alkalic suite from Murray Basin and Black Hill drill core - filled green triangles, AFB outcropping mafic rocks (Adelaide Hills, Fleurieu Peninsula, Kangaroo Island ) – filled blue squares, tholeiite series from Murray Basin drill core – open purple circles. B)

Global back arc basalt (BAB) data from current back arc basins. Data from GEOROC.

Figure 9

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A) Delamerian mafic rocks plotted on the Zr/4 – Nb*2-Y discrimination diagram (Meschede, 1986). – E-MORB , D – N-MORB , C,D – Volcanic arc basalt.

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Symbols as for figure 8. Defined fields : AI,AII – within plate alkalic , AII,C – within plate tholeiitic , B

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B) Global back arc basalt data (GEOROC) plotted on the Zr/4 – Nb*2-Y discrimination diagram (Meschede, 1986)

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C) Delamerian mafic rocks plotted on the La/10 – Y/15 – Nb/8 discrimination diagram (Cabanis and Lecolle, 1989). Symbols as for figure 8. Defined fields: VAT – volcanic arc tholeiities, NMORB,

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EMORB, Continental basalts, alkaline intercontinental rift basalts, calc-alkaline basalts, back arc basalts (*). The arrow denotes the trend towards continental crustal contamination.

(Cabanis and Lecolle, 1989).

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Figure 10

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D) Global back arc basalt data (GEOROC) plotted on the La/10 – Y/15 – Nb/8 discrimination diagram

A) Delamerian mafic rocks plotted on the V v Ti/1000 discrimination diagram (Shervais, 1982; Tetley et al., 2019). Symbols as for figure 8. In addition Magdala basalts from the eastern edge of the Mt Stavely Volcanic belt western Victoria – red diamonds. B) Global back arc basalt data (GEOROC) plotted on the V v Ti/1000 discrimination diagram (Shervais, 1982; Tetley et al., 2019). Figure 11 Comparison (CaO/Al2O3 v MgO, Cr ppm v MgO, chondrite-normalised REE patterns) between the high Mg andesites (red stars) from drill hole KTH12 in the eastern South Australian Murray Basin (Figs 1 and 2) and data from the global boninite data set (GEOROC). High Ca boninites (with CaO/Al2O3 . 0.5; Crawford et al., 1989) – purple crosses, Low – Ca boninites – open black circles Figure 12 Delamerian intermediate to felsic magmatic rocks plotted on the Normative Ab-An-Or diagram. A) S-type granites – open blue circles, I-type granites – filled blue circles, Kinchina / Monarto adakites – open red stars.

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Journal Pre-proof B) A-type granites – filled red circles, Mt Stavely andesites, dacites and dacitic porphyries – yellow crosses, Murray Drill core intermediate to felsic rocks (excluding members of the A-type granite suite) – open purple crosses. Figure 13 A), B) Delamerian intermediate to felsic magmatic rocks plotted on the SiO2 – MALI (modified alkali-lime index) diagram (Frost et al., 2001) . Symbols as in Figure 12. C), D) Delamerian intermediate to felsic magmatic rocks plotted on the molar A/NK v A/CNK (Shand, 1943). Symbols as in Figure 12. Figure 14 Chondrite normalized rare earth and normalized incompatible element diagrams for Delamerian felsic to

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intermediate rocks ; A) S-type granites from AFB outcrop, C) I-type granites from AFB outcrop , E) Mt Staveley andesite and dacite lavas and porphyry .

ro

B, D and F primitive mantle normalized incompatible trace element diagrams. B) S-type granites, D) I-type

-p

granites, F) Mt Staveley lavas. Figure 15

re

Chondrite normalized rare earth and normalized incompatible element diagrams for Delamerian felsic to intermediate rocks ; A) Adakite granite from Kinchina quarry AFB, C) A-type granites from Murray Basin ,

lP

E) Intermediate lavas and intrusives from Murray Basin.

B, D and F primitive mantle normalized incompatible trace element diagrams. A) Adakite granite from

Murray Basin. Figure 16

na

Kinchina quarry AFB, C) A-type granites from Murray Basin, E) Intermediate kavas and intrusives from

Jo ur

A), B) Delamerian intermediate to felsic magmatic rocks plotted on the Rb v Y+Nb granitic rock discrimination diagram (Pearce et al., 1984). Symbols as in Figure 12. C), D) Delamerian intermediate to felsic magmatic rocks plotted on the Y v Nb granitic rock discrimination diagram (Pearce et al., 1984). Symbols as in Figure 12. Fields; VAG – volcanic arc granites, Syn-COLG – syn collisional granites, WPG – within plate granites, ORG – orogenic granites. Figure 17. Wt% SiO2 v Wt% TiO2 showing intermediate to felsic lavas and iintrusives from Murray Basin core exclusive of the A-type granite samples. Grey circles are data from a very characteristic subduction-related modern arc calc alkaline volcano, Rindjani from the eastern Sunda Arc, Indonesia (Elburg et al., 2007; Foden, 1983). Red circles are intermediate to felsic samples from Murray Basin core that are most like modern island arc subduction suites. Blue diamonds are Murray Basin core samples that are unlike modern arc suites and seem rift related or anorogenic. Figure 18.

41

Journal Pre-proof

Collected Delamerian basalt data (Symbols as in Fig. 8) and the post tectonic A-type granites (*). Mg# vppm Ti and Mg# v ppm Zn showing the apparent disconnection of the alkali basalt suites from the A-type granites. Figure 19 Nd(500)values v 147Sm/144Nd ratios for Delamerian magmatic suites and Kanmantoo sedimentary rocks from South Australia and western Victoria. New unpublished data is listed in table 5. Other magmatic sample data from (Foden et al., 2006; Foden et al., 2002a; Foden et al., 2002b; Turner et al., 1996). Kanmantoo data from (Foden et al., 2002a; Haines et al., 2009; Turner et al., 1993). Symbols: Kanmantoo group sedimentary rocks – black crosses, S-type granites – open circles, I-type granites filled blue circles (in Fig 19A) , A-type

of

granites – filled red circles (in Fig. 19A), Kinchina/ Monarto adakite – open diamonds, mafic rocks from the exposed AFB and from Murray drill core – filled black squares, Murray basin intermediate to felsic

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volcancis and intrusives (excluding A-type granite) - X symbols. Blue square – average MORB at 500Ma.

-p

A) Illustrates the wedge-shaped distribution of the mafic samples converging on contemporary MORB. Variation without initial Nd variation reflects pure fractional crystallization or varying degrees of source

re

melting. Positive co-variation of Nd and 147Sm/144Nd reflects crustal contamination of mafic magma leading to I- and A-type granite fields. Inset depicts AFC trends (using the equations of DePaolo (1981) and Powell

lP

(1984)) calculated between contemporary MORB (Nd = +8.2, Nd = 9.5 ppm, Sm = 3.34 ppm) and mean Kanmantoo (Nd = -13.5, Nd = 51.7 ppm, Sm = 9.48 ppm). Calculation made for three different assimilation

na

to fractional crystallization ratios (‘r’ values), r = 0.35, 0.15 and 0.05. Intervals on the curves are 10% crystallization. The curves extend to 50% crystallization. These trends demonstrate the reduction in crustal

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contamination in the transition from the syn-tectonic I-type suite to the post-tectonic A-type suite. As also indicated the S-type granites reflect direct mixing of Kanmantoo sediment melts with intruding I-type magmas (as illustrated by field evidence at Kanmantoo migmatite complexes (Foden et al., 2002a; Schwindinger and Weinberg, 2017).

B) Symbols as for A) with the addition (shown as green diamonds) of boninite suite rocks form SA drill hole KTH12, from Mt Stavely andesite and dacite lavas and shallow intrusions (the Larnakardo porphyry, Bowman et al., 2019) and Magdala basalt samples from outcrop 5 km east of the Stavely outcrops. The red curves are the best fit to model the boninite suite rocks as AFC derivatives of the parental Magdala basalt, noting the extremely small required ‘r; values (0.02 – 0.006). Intervals on the curves are 10% crystallization. The curves extend to 80% crystallization. As discussed in the text, given the relatively high MgO, Ni, Cr and Sc of the Mt Staveley lavas and the KTH12 high Mg andesites, the process modeled by these curves is not viable and the alternative of subduction driven source mantle wedge contamination is much more likely. Figure 20 Figure 20 illustrates the model presented here for magmatic evolution in the Cambrian Gondwanan margin r in SE Australia.

42

Journal Pre-proof Tables; Table1 Name and location of drill holes sampled Table 2 Ar-Ar analyses Table 3 Summary of U-Pb dates on zircons and monazite Table 4 Representative whole rock analyses

Jo ur

na

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ro

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Table 5 Nd-Sm and Sr-isotope analyses

43

Journal Pre-proof

Table 1. Sampled Murray Basin Drill Cores

Coonalpyn-2 Coonalpyn-1 PD1 MTR12 MTR13 PADD28 KTH-011 KTH-005 KTH-004 PADD31 MTR10 PADD33 KTH-01 PADD32 KTH-02 KTH-03 KTH-012 PG4

BA, BA, BA, BA,BT BA BT BT IF BA BA IF AG,IF,BA,BT, BSA BSA BSA AG IF,BT IF IF BA BA BSA, BT BA BA BA IF AG AG BT BON AG

354951 382352 382237 380735 384796 384340 382939 333235 365171 368453 362521

of

Easting Northing 347842 6165607 343470 6165590 342900 6162660 366291 6098108 402421 6092278 382661 6076411 379240 6075154 354951 6074507

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ro

6074507 6074497 6073633 6071595 6070393 6069994 6069664 6068679 6067778 6064778 6064678

re

lP

na

KMD-07

Rock Type AG, BA BT IF,BSA BT,IF BT, IF BSA BA, BT

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Drill Core S10 119104 S11 COP56 WYN1 Yumali-6 Yumali-9 Nanyah Mason Lookout (DDH1) Yumali-7 Coomandook Yumali-5 Yumali-4 Yumali-3 Yumali-2 M161 COP57 COP55 COP58

379614 403043 401595 389521 392822 390521 443201 426771 424652 425422 433241 399863 403196 429938 403878 430374 430301 436771 442734 44

6041096 6040969 6038448 6036677 6017478 6017477 6008676 6007378 6004578 5991558 5988578 5985278 5985269 5980113 5972405 5971192 5971186 5969177 5958339

Journal Pre-proof

Jo ur

na

lP

re

-p

ro

of

PG11 AG 442583 5956312 PG5 AG 443519 5955907 LD3 IF 459556 5931261 https://minerals.sarig.sa.gov.au/SearchResults.aspx AG - A-type granite, BA - Alkali basalt, BT - Tholeiitic basalt/intrusive IF - Intermediate to Felsic Volcanics and Intrusives, BSA - Sub-Alkali Basalt BON - High Mg Andesite/ Boninite

45

Journal Pre-proof

Table 2. Ar-Ar Geochronology Sample

Laboratory Number

Unit

Muscovite HRM-m

Kanmantoo Grp

Muscovite HRM-m2

Kanmantoo Grp

Muscovite HRM-m3

Kanmantoo Grp

Muscovite HRM-m tot

Kanmantoo Grp

Plateau Coordinates Age (Ma,±2) 501.3 ± 18 35o44'53"S 136o38'20"E 504.7 ± 5.5 35o44'53"S 136o38'20"E 501 ± 4.9 35o44'53"S 136o38'20"E 502.4± 4.4 35o44'53"S 136o38'20"E

l a

92 100

0.85 519± 65

0.15

0.99 516± 16

102

0.29

0.96 497± 9.5

346

r P

0.34

1 498±9.5

133

n r u

o J

46

f o

o r p

e 97

Isochron Age (Ma,±2s)

Ar/36Ar Intercept (±1) 342

Total 39Ar P Released MSWD (%) 100 0.27

40

Journal Pre-proof

Table 3. Summary of U-Pb Dating of Zircon and Monazite Magma Sample Suite A-type PADD28 Granite A-type 1109-7 Granite A-type JF07-118 Granite KW08A-type 15 Granite A-type JF07-108 Granite JF07A-type 114b Granite LD3 Murray Core PADD32 Murray Core JF09Mt Stavely 11/12 Volc. CG17

Adakite

Eastin g

Age (Ma, ± Northing 2s)

Rock Type

Mineral

Locality

Granite

zircon

Core

443201

6008677

475.2 ± 1.4

6.1

21

Granite

zircon

Mannum

350102

6137630

482.7 ± 2.3

4.9

11

Granite

zircon

Marcollat

442594

5956187

478.2 ± 0.8

3.5

51

Granite

zircon

Monteith

352868

6106504

470.1 ± 1.4

3.2

35

Granite

zircon

Mt Monster

438634

5993813

472.5 ± 1

2.8

34

Granite Qtz Diorite Granodiorite Dacite Porphyry

zircon zircon zircon

Kongal Rocks

450411 459556 403878

5974957 5931261 5972405

486.1 ± 1 475.2 ± 1.4 516.1 ± 2

2.9 0 0.6

33 13 10

Mt Stavely Arc, W. Vic. 643406 Monarto Kinchina Quarry 334885

5835528

504.7 ± 2.3

0.55

13

6118365

495.0 ± 1.6

1.6

51

Granite

zircon monazit e

Core Core

l a

rn

u o

ro

-p

e r P

J

47

f o

MSWD

n

Jo u

rn

al

Pr

e-

pr oo f

Journal Pre-proof

48

Journal Pre-proof Table 4. Representative Whole Rock Analyses. Sam Sui D Roc Lo E No S A ple te ril k cal as rth i l2 l type ity ti ing O O C ng 2 3 or e Thol eiites CG 18 11

CG 18 29

R164 L75

R177

Tho leiit ic Maf ic Roc ks in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Tho leiit ic Maf ic Roc ks in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Tho leiit ic Maf ic Roc ks in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Tho

Ou tcr op

doleri te

Kin chi na Qu arr y

33 70 07

611 350 2

4 9. 2 7

13 .5 0

T Fe M M C N K P L T M A B C C C C C D E E G G H K L L L N N N P P P R S S S T T T i 2O n g a a2 2 2 O o g S a e o r s u y r u a d o a i u b d i b r b c m r b h i O 3T O O O O O O I t # I al 2 5

T U V Y Y Z Z m b n r

2. 5 9

14. 84

0. 2 6

6. 1 6

8. 4 5

2. 39

0. 7 8

0. 3 5

0. 6 1

9 9. 2 0

0. 4 5

0 . 6 7

3 6

5 8

1 3 0

0

7 5

9 . 8

6 . 0

2 . 3

2 4

8 . 8

2 . 1

6 4 7 5

1 3. 4

0 . 8

1 1. 0

2 6. 0

5 0

1 5 1 0

2

5 . 2

2 0. 6

3 9 . 0

7 . 8

2 4 0

1 . 5 4

3 . 1

1 5 5 2 4

0. 8 0

0 . 7

4 4 0

5 0. 4

5. 4 5

7 6

2 8 0

0 . 6

1 1. 5

2 2. 8

4 4

1 1 7 0

3

4 . 4

3 6. 8

3 7 . 0

6 . 7

2 3 0

1 . 2 6

4 . 3

1 1 8 0 8

0. 7 0

1 . 4

3 2 0

4 2. 8

4. 5 5

7 0

2 7 0

f o

Ou tcr op

doleri te

Kin chi na Qu arr y

33 70 07

611 350 2

5 1. 0 2

14 .2 0

1. 9 7

12. 81

0. 2 0

6. 0 1

8. 9 6

2. 37

0. 8 7

0. 2 7

0. 6 3

9 9. 3 1

0. 4 8

0 . 6 7

4 0

2 9

5 4

1 6 0

l a

1

2 2 0

r P

e

o r p

8 . 4

5 . 0

2 . 0

2 1

7 . 4

1 . 8

7 2 2 2

1 0. 9

n r u

o J Ou tcr op

Doler ite

Ta nun da

31 61 86

617 540 8

5 0. 4 1

14 .2 9

0. 9 6

9.9 7

0. 1 7

7. 8 9

1 1. 8 8

2. 42

0. 6 2

0. 1 0

0. 5 9

9 9. 3 0

0. 6 1

0 . 5 4

1 7 1

1 8

5 5

1 8 7

4 5

1 5

5 1 4 7

4. 0

5. 2

7. 0

5 1

4 3 6

4

2 0. 3

3 8 . 3

8 7

3 . 2

5 7 5 4

0 . 6

2 5 7

2 7. 0

8 1

6 5

Ou

Doler

Ta

31

617

4

19

0.

7.0

0.

6.

1

2.

0.

0.

0.

9

0.

0

1

1

5

3

3

1

4

6.

2.

8.

6

2

2

1

3

1

3

3

1

1

2

4

2

49

Journal Pre-proof L483

MTR 12-01

MTR 12-02

MTR 12-03

WYN 1-01

Subalkali Basalt s F0708 FO60 8

KMD -0701

KMD -0701

KMD -0701

KMD -0701

leiit ic Maf ic Roc ks in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Tho leiit ic Maf ic Tho leiit ic Maf ic Tho leiit ic Maf ic Tho leiit ic Maf ic

tcr op

ite

M TR 12

Sub alka lic maf ic Sub alka lic maf ic Sub alka lic maf ic Sub alka lic maf ic Sub alka

nun da

61 86

540 8

9. 1 8

.9 0

5 1

8

1 0

3 8

2. 7 2

71

5 3

0 5

Ande site

39 28 21

601 747 7

5 5. 0 2

17 .2 1

1. 1 3

12. 55

0. 2 2

4. 8 6

2. 5 5

5. 13

1. 1 3

0. 2 0

M TR 12

Ande site

39 28 21

601 747 7

5 4. 4 2

18 .6 0

1. 2 1

11. 15

0. 2 0

4. 6 9

1. 6 5

6. 64

1. 2 4

0. 2 1

M TR 12

Basal t

39 28 21

601 747 7

5 3. 6 0

16 .1 4

1. 0 3

12. 25

0. 2 0

4. 5 8

4. 5 6

4. 92

2. 5 3

0. 1 9

W Y N1

Basal t

40 24 21

609 227 8

5 0. 8 4

15 .5 2

1. 2 3

11. 22

0. 2 0

7. 0 8

8. 5 5

4. 21

1. 0 1

0. 1 6

Ou tcr op

Basal t/ Doler ite

K M D07

Mo ntei th

8 2

9. 9 8

6 4

. 7 1

3 1

7

2

2 2

1 0 0. 0 0 1 0 0. 0 0 1 0 0. 0 0 1 0 0. 0 0

0. 4 3

1 . 2 0

2 1 7

2 0

0

7

2

4 . 3

2 . 6

1 . 2

1 8

3 . 5

0 . 8

0. 4 5

1 . 2 2

2 4 6

1 4

0

7

1

4 . 0

2 . 6

0 . 7

1 9

3 . 0

0 . 8

0. 4 3

0 . 8 4

4 8 2

2 1

0

7

4

4 . 0

2 . 4

1 . 2

1 6

3 . 3

0 . 8

0. 5 6

0 . 6 6

2 2 5

2 0

0

2 4 3

6 . 5

4 . 3

1 . 3

1 6

4 . 8

1 . 3

0. 5 3

0 . 6 4

1 8 6

4 7

6 5

9 6

o J

n r u

l a

7

5

r P 1

2 0

0

9 4 0 1

5. 0

f o

o r p

e

4 0 0

6

0

6

1 8

0. 9

0 . 0

0 7

. 3

0 5 7

. 6

8 0

3. 4

6

5

0 . 0

0 . 4

0. 8

1 2. 0

6

8 6 1

8

2 5. 4

3 0 . 5

3 . 2

2 6 4

0 . 6 8

3 . 9

6 7 8 8

0. 3 5

1 . 7

3 3 4

2 5. 4

2. 5 0

1 5 7

6 0

1 0 3 2 8 2 1 0 1 4 8 4 0 9

5. 0

0 . 0

0 . 4

2. 8

1 0. 0

6

8 9 7

7

2 7. 6

3 5 . 2

2 . 8

1 4 9

0 . 6 4

3 . 0

7 2 7 3

0. 4 0

0 . 5

3 5 1

2 7. 7

2. 6 0

1 5 9

6 0

6. 0

0 . 0

0 . 4

2. 1

1 2. 0

3

8 1 8

4

6 4. 1

3 2 . 7

3 . 2

1 7 0

0 . 6 6

2 . 7

6 1 8 2

0. 3 5

0 . 0

3 2 9

2 3. 6

2. 5 0

1 3 1

5 8

4. 0

0 . 0

0 . 6

2. 2

1 4. 5

7 9

6 7 7

2

3 1. 7

3 2 . 6

4 . 3

2 1 1

1 . 0 5

0 . 2

7 3 7 3

0. 5 5

0 . 4

2 3 8

4 0. 2

4. 0 0

7 6

1 3 9

8 2 3 5

1 1. 0

1 9. 5

1 4. 0

5 8

1 1 0 0

8

4 4. 3

2 9 . 8

2 . 5

9 2 9 7

0 . 3

2 4 5

1 9. 0

6 0

1 1 0

35 28 68

610 650 4

4 5. 1 6

19 .6 6

1. 5 5

8.9 1

0. 1 5

5. 0 2

1 3. 6 8

2. 92

0. 9 9

0. 2 5

1. 8 7

1 0 0. 1 6

Basal t/ Doler ite

37 96 14

604 109 6

4 5. 2 5

18 .1 9

0. 7 5

11. 12

0. 1 3

9. 7 1

9. 3 0

2. 22

0. 6 5

0. 1 1

1. 7 3

9 9. 1 6

0. 6 3

0 . 8 6

7 8

1 5

1 0 8

2 3 0

9

1 8 7 0

2 . 6

1 . 6

0 . 9

1 5

2 . 5

0 . 5

5 3 9 6

6. 6

3 0 . 0

0 . 2

4. 1

9. 1

1 2 4 0

4 8 0

5

2 . 1

3 7. 2

1 1 . 0

2 . 2

3 3 4

0 . 4 2

1 . 1

4 4 9 5

0. 2 1

0 . 3

1 1 1

1 4. 0

1. 3 6

8 2

7 2

S2

Basal t/ Doler ite

37 96 14

604 109 6

4 5. 4 9

18 .1 6

0. 4 6

8.6 3

0. 1 2

1 2. 8 0

9. 1 0

1. 56

0. 7 2

0. 0 7

2. 6 5

9 9. 7 6

0. 7 5

0 . 9 1

1 1 5

1 3

6 5

6 8 0

1 6

1 1 1

1 . 6

1 . 0

0 . 6

1 5

1 . 6

0 . 3

5 9 7 7

6. 0

3 0 . 0

0 . 1

3. 0

6. 5

2 1 6

3 0 5

8

1 . 6

5 0. 0

7 . 0

1 . 5

3 2 4

0 . 2 5

1 . 6

2 7 5 7

0. 1 2

0 . 4

6 5

8. 8

0. 8 5

8 3

4 0

K M D07

Basal t/ Doler ite

37 96 14

604 109 6

4 5. 9 5

17 .7 0

0. 9 6

10. 92

0. 1 3

9. 5 9

9. 5 5

2. 49

0. 3 7

0. 1 4

1. 1 9

9 8. 9 9

0. 6 4

0 . 8 1

6 8

1 8

1 0 1

2 1 0

5

1 9 5 0

3 . 2

1 . 9

1 . 1

1 6

3 . 1

0 . 6

3 0 7 1

7. 8

1 0 . 0

0 . 3

5. 1

1 0. 7

1 2 5 0

6 1 1

4

2 . 4

1 1. 8

1 7 . 0

2 . 7

3 3 8

0 . 5 2

1 . 0

5 7 5 4

0. 2 7

0 . 3

1 4 5

1 7. 0

1. 6 0

7 4

9 5

K M D-

Basal t/ Doler

37 96 14

604 109 6

4 6. 6

15 .2 6

1. 5 8

13. 39

0. 7 5

7. 1 9

6. 6 4

2. 70

1. 9 0

0. 2 4

3. 1 4

9 9. 4

0. 5 2

0 . 8

2 3 4

3 9

3 7

2 0 0

8

2 7

6 . 0

3 . 5

1 . 7

2 1

5 . 8

1 . 2

1 5 7

1 7. 1

6 0 .

0 . 5

1 0. 0

2 0. 7

8 5

1 0 4

7 5

5 . 0

2 1 9.

2 7 .

5 . 3

2 5 5

0 . 9

3 . 7

9 4 7

0. 4 9

0 . 9

2 2 0

3 3. 1

3. 1 8

9 3 2

1 7 3

50

5 4 9

Journal Pre-proof lic maf ic Sub alka lic maf ic Sub alka lic maf ic Sub alka lic maf ic Sub alka lic maf ic

07

ite

K M D07

Basal t/ Doler ite

37 96 14

604 109 6

4 7. 6 0

17 .8 2

0. 7 8

8.8 7

0. 1 3

1 1. 4 5

9. 5 0

2. 04

0. 5 9

0. 1 0

1. 0 7

9 9. 9 5

0. 7 2

0 . 8 4

1 0 6

1 9

7 8

2 3 0

8

9 7

2 . 6

1 . 6

0 . 9

1 5

2 . 6

0 . 6

4 8 9 8

8. 7

1 0 . 0

0 . 2

5. 3

1 0. 0

2 2 2

4 3 6

7

K M D07

Basal t/ Doler ite

37 96 14

604 109 6

5 0. 7 2

15 .4 8

1. 6 4

10. 53

0. 1 8

6. 7 1

9. 3 7

2. 95

0. 7 9

0. 2 4

0. 9 3

9 9. 5 4

0. 5 6

0 . 6 8

1 8 9

4 0

4 3

3 1 0

4

5 9

5 . 9

3 . 6

1 . 8

2 0

6 . 1

1 . 3

6 5 5 8

1 7. 8

1 0 . 0

0 . 5

1 0. 5

2 2. 4

6 3

1 0 4 7

K M D07

Basal t/ Doler ite

37 96 14

604 109 6

5 1. 3 4

15 .2 0

1. 6 2

9.7 1

0. 2 5

4. 8 1

6. 8 8

4. 69

1. 8 0

0. 2 3

2. 8 3

9 9. 3 6

0. 5 0

0 . 6 9

1 9 7

5 3

4 2

1 4 0

1

4 7

7 . 0

4 . 1

1 . 8

2 1

6 . 7

1 . 4

1 4 9 4 2

2 3. 7

4 0 . 0

0 . 6

1 3. 0

2 6. 2

3 4

K M D07

Basal t/ Doler ite

37 96 14

604 109 6

5 2. 9 7

16 .1 6

0. 7 1

8.1 9

0. 1 6

6. 6 6

8. 0 9

3. 06

1. 3 6

0. 1 8

1. 7 0

9 9. 2 4

0. 6 2

0 . 7 6

2 3 4

4 2

3 5

2 6 0

5

2 7

5 . 4

3 . 3

1 . 5

1 9

5 . 3

1 . 2

1 1 2 8 9

1 9. 2

2 0 . 0

0 . 5

9. 2

2 1. 3

Alk alic Maf ic

C OP P5 5

Basal t

36 84 53

606 477 8

5 2. 9 5

17 .5 6

1. 7 6

9.7 4

0. 1 5

4. 6 3

7. 2 5

3. 61

1. 8 6

0. 4 9

4 8. 0

0 . 0

0 . 4

2 6. 6

MTR 10-01

Alk alic Maf ic

M TR 10

Basal t

39 98 63

598 527 8

4 9. 5 4

16 .7 7

2. 0 4

10. 99

0. 2 1

4. 3 2

9. 5 9

3. 64

2. 5 4

0. 3 5

3 5. 0

0 . 0

0 . 3

PAD D3108

Alk alic Maf ic

PA D D3 1

Basal t

43 32 41

598 857 8

4 6. 0 1

15 .8 6

3. 0 6

13. 82

0. 2 1

8. 7 0

6. 8 9

4. 38

0. 6 3

0. 4 4

1 5 4 0 0 2 1 0 7 8 5 2 3 0

2 1. 0

0 . 0

PAD D3104

Alk alic Maf ic

PA D D3 1

Basal t

43 32 41

598 857 8

4 7. 3 6

15 .5 4

3. 8 3

16. 76

0. 1 5

8. 8 5

3. 5 3

0. 70

2. 7 3

0. 5 6

2 5. 0

PAD D3105

Alk alic Maf ic

PA D D3 1

Basal t

43 32 41

598 857 8

4 0. 5 1

13 .4 9

3. 2 0

14. 64

0. 2 3

9. 1 6

1 5. 3 0

1. 20

1. 1 1

1. 1 5

2 2 6 4 4 9 2 0 8

PAD D3304

Alk alic Maf ic

PA D D3 3

Basal t

40 31 96

598 526 9

4 5. 9 4

17 .4 2

3. 9 5

14. 74

0. 1 9

5. 4 3

6. 3 6

2. 81

2. 5 5

0. 6 1

F0706 FO60 6

Alk alic Maf ic

Ou tcr op

Basal t

Mo ntei th

35 28 68

610 650 4

4 5. 6 7

18 .8 7

1. 8 6

9.7 6

0. 1 5

5. 2 0

1 0. 2 5

4. 82

0. 4 5

0. 2 7

2. 6 0

F0707 FO60 7

Alk alic Maf

Ou tcr op

Basal t

Mo ntei th

35 28 68

610 650 4

4 6. 6

16 .3 6

1. 9 8

11. 51

0. 1 8

6. 2 4

1 0. 5

3. 99

0. 4 7

0. 2 9

1. 6 3

KMD -0701

KMD -0701

KMD -0701

KMD -0701

Alkali Basalt s COP5 5-01

3

2

1 0 0. 0 0 1 0 0. 0 0 1 0 0. 0 0 1 0 0. 0 0 1 0 0. 0 0 1 0 0. 0 0 9 9. 8 9

2

0. 4 9

0 . 8 3

5 8 0

0. 4 4

0 . 6 4

6 6 0

0. 5 6

0 . 7 8

0. 5 1

1 0 0

0

l a

2

2

e 5 . 5

3 . 0

2 9

5 . 0

r P

2 . 0

2 5

7 . 0

1 . 0

2 . 3

2 . 2

1 9

6 . 5

0 . 9

0

3 0

9 9

5 5

0

7 2

1

5 . 5

2 . 5

2 . 2

2 3

7 . 0

0 . 9

1 . 4 8

1 3 0

7 5

0

3 9

1

7 . 0

3 . 3

2 . 9

2 8

9 . 5

1 . 2

0. 5 5

0 . 4 4

6 7 4

7 5

0

4 3

0

6 . 5

3 . 0

2 . 8

2 1

9 . 0

1 . 1

0. 4 2

0 . 9 2

9 9 3

6 5

0

1

2

6 . 5

2 . 9

2 . 7

2 2

8 . 5

1 . 1

0. 5 1

0 . 7 0

2 1 6

4 5

6 6

5 0

1 9

0. 5 2

0 . 6

1 8 6

5 5

6 8

7

2 1

51

0

0

0

2 . 4

3 2. 3

1 3 . 0

2 . 5

3 1 0

0 . 4 3

3 . 6

4 6 7 5

0. 2 4

0 . 9

1 1 7

1 4. 9

1. 5 0

7 6

8 1

8

5 . 1

3 3. 9

3 3 . 0

5 . 7

3 0 2

0 . 9 7

4 . 1

9 8 3 0

0. 5 3

1 . 0

2 5 7

3 3. 7

3. 1 1

1 0 2

1 5 4

1 0 0 4

2 5 5

6 . 7

7 4. 5

3 0 . 0

6 . 4

1 6 4

1 . 0 8

8 . 0

9 7 1 0

0. 6 4

1 . 9

2 2 7

3 9. 3

3. 7 8

2 3 5

1 8 0

7 9

7 8 5

2 2

5 . 3

1 1 4. 0

2 5 . 0

5 . 0

3 2 3

0 . 8 5

5 . 4

4 2 5 6

0. 4 9

1 . 3

1 1 5

3 0. 2

3. 0 8

1 2 2

1 8 5

4 1. 0

1 2

2 1 2 4

8

6 0. 3

2 4 . 6

8 . 0

6 1 2

1 . 0 0

1 2 . 0

0. 4 0

2 . 1

2 2 8

3 1. 8

2. 6 0

1 1 6

1 4 7

1 7. 5

4 0. 5

2 1

1 5 4 5

2 6

2 4 2. 2

3 2 . 1

8 . 5

6 3 8

0 . 9 6

1 3 . 2

0. 3 0

1 . 0

3 6 1

2 6. 5

2. 1 0

1 2 2

1 3 1

0 . 3

3 5. 1

2 9. 5

7 8

1 9 1 0

2

1 6. 9

3 0 . 6

7 . 0

6 5 3

0 . 9 8

4 . 3

0. 3 0

1 . 4

3 3 5

2 8. 0

1. 9 0

1 3 9

1 7 7

0 . 0

0 . 3

4 9. 6

3 8. 0

2 7

2 4 4 5

2

5 0. 9

2 3 . 1

9 . 0

2 0 9

1 . 3 0

3 . 9

0. 4 0

0 . 0

3 0 3

3 5. 4

2. 6 0

1 6 6

2 7 2

2 9. 0

0 . 0

0 . 3

3 7. 1

3 8. 5

2 0

5 0 4 0

2

1 9. 8

2 1 . 6

8 . 5

1 5 1

1 . 2 0

4 . 1

0. 4 0

0 . 9

2 7 9

3 5. 5

2. 3 0

1 2 6

2 0 3

2 1 1 6 1 3 7 3 5

2 0. 0

0 . 0

0 . 3

3 4. 6

3 3. 5

2 7

2 6 8 3

5

5 9. 1

2 2 . 3

8 . 5

3 0 8

1 . 1 5

5 . 6

0. 3 5

1 . 5

2 7 2

3 2. 3

2. 3 0

1 4 6

2 2 9

1 6. 0

2 2. 4

1 4. 0

6 0

1 1 9 1

8

1 2. 5

3 3 . 2

7 7 4

3 . 4

1 . 0

2 7 3

2 0. 6

7 5

1 2 3

3 9 3

1 4. 0

2 1. 6

1 7. 0

6 0

1 2 6

7

1 7. 8

3 9 .

5 6 4

3 . 9

1 0 5 7 3 1 2 2 4 9 1 8 3 6 9 2 2 9 4 2 1 9 1 9 2 2 3 6 5 7 1 1 1 1 9 1 1 8

0 . 0

3 5 5

2 4. 5

8 1

1 3 3

f o

o r p

7 5

n r u

o J

9 9. 8

7 2

7

8

1

Journal Pre-proof ic KW0 8-2

HighMg Andes ite/Bo ninite 115419

115420

KTH1 2-01

KTH1 2-02

Mt Stavel y Volca nics and Magd ala Low Ti Thole iite/ Bonin ite VIC 02

6

3

4

2

5

Dol erite

Ou tcr op

Doler ite

Sed an

34 91 49

618 251 8

5 6. 7 2

14 .9 1

2. 2 2

11. 19

0. 2 0

2. 3 0

3. 4 1

4. 55

3. 0 7

0. 4 1

0. 1 6

9 9. 1 4

0. 2 9

0 . 8 8

5 5 6

3 7 8

3 6

4

Bon inite (Dri ll hole KT H012 ) Bon inite (Dri ll hole KT H012 ) Bon inite (Dri ll hole KT H012 ) Bon inite (Dri ll hole KT H012 )

K T H12

bonin ite

Kei th

43 67 71

596 917 7

5 7. 5 2

13 .5 4

0. 5 5

7.6 4

0. 1 3

8. 8 0

5. 7 7

2. 10

1. 5 7

0. 1 1

2. 7 0

1 0 0. 4 3

0. 7 0

0 . 8 7

2 1 7

3 3

6 3

6 3 3

6 4

K T H12

bonin ite

Kei th

43 67 71

596 917 7

5 7. 2 5

13 .4 8

0. 5 4

7.4 1

0. 1 2

8. 7 9

5. 1 7

1. 98

1. 4 7

0. 1 1

3. 4 3

9 9. 7 5

0. 7 0

0 . 9 5

2 1 7

4 0

6 4

5 9 9

4 6

Ma gdal a Bas alt east of

K T H12

bonin ite

Kei th

43 67 71

K T H12

bonin ite

Kei th

43 67 71

Ou tcr op

Boni nite

Sta wel l Zo ne Vic

66 87 52

596 917 7

5 8. 8 6

13 .6 4

0. 5 4

7.5 8

0. 2 4

9. 1 9

5. 8 1

2. 40

1. 6 4

0. 1 1

1 0 0. 0 0

596 917 7

5 8. 7 5

13 .7 9

0. 5 4

7.7 1

0. 1 3

8. 8 0

5. 8 1

2. 69

1. 6 6

0. 1 1

1 0 0. 0 0

586 225 6

5 1. 4 1

14 .9 6

0. 1 8

9.5 7

0. 1 6

8. 8 4

1 2. 4 6

1. 38

0. 0 5

0. 0 5

9 9. 0 6

0. 7 1

0 . 8 4

2 2 3

3 1

l a

o J

n r u 0. 6 9

0 . 8 2

2 3 2

0. 6 5

0 . 6 0

2 1

0

5 9 3

3 3

0

5 5 2

1 0

8 3

4 6 0

4

3

3 1

5 0 . 0

8 . 5

2 . 8

1 . 6

2 . 9

1 . 6

2 3

2 5 4 8 4

1 8 0. 0

1 4

1 3 0 3 3

1 6

9 . 5

3 . 7

7

1 3 6. 7

1 7 5. 0

6

1 7 8 9

7

1 4. 0

6. 9

1 4. 0

1 8 8

4 8 0

1 2 2 0 2

1 5. 0

7. 8

1 4. 0

1 8 6

f o

8 0 . 0

2 0 9. 4

1 8 . 6

6 0 . 0

1 8 3

0 . 2 0

6 0 . 1

1 5

5 4. 5

2 2 . 7

1 4 9

8 . 9

4 8 0

1 8

5 3. 5

2 2 . 6

1 3 5

8 0 1 3 3 0 7

4. 1 0

2 9 . 9

1 2 7

2 5 7. 2

3 2 9 7

2 . 2

1 5 0

8 . 6

3 2 3 7

1 . 8

2 8. 5 0

1 4 8

1 6 1 9

1 6. 1

6 4

1 1 6

1 4 1

1 6. 3

6 0

1 1 6

0 . 7

1 4

2 . 6

0 . 5

1 3 5 8 6

1 3. 0

0 . 0

0 . 2

7. 2

1 3. 5

1 7 7

4 9 1

1 0

5 3. 7

2 3 . 4

2 . 9

1 5 7

0 . 4 8

7 . 3

3 2 5 0

0. 2 5

1 . 6

1 4 7

1 6. 6

1. 6 5

6 6

1 1 0

0 . 8

1 4

2 . 7

0 . 5

1 3 7 6 6

1 2. 0

0 . 0

0 . 2

7. 7

1 4. 5

1 8 1

4 9 1

1 0

6 1. 3

2 3 . 9

3 . 0

1 6 5

0 . 5 0

9 . 2

3 2 5 2

0. 2 5

2 . 1

1 3 8

1 7. 7

1. 6 5

7 0

1 1 0

4 1 5

1. 0

0. 1

1. 0

1 6 5

2 1 8

0

0. 5

4 6 . 7

1 . 1

1 0 7 9

0 . 2

2 0 0

8. 5

6 9

6

1 2

52

4 9 . 5

o r p

e

r P 3

2 8 . 5

6

5 9

Journal Pre-proof

VIC 07

MTS/ 3/02

MTS/ 6/02

MTS/ 2/02

MTS/ 4/02

MTS/ 1/02

Mt Stav ely Belt , VIC Ma gdal a Bas alt east of Mt Stav ely Belt , VIC Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria

Ou tcr op

Boni nite

Sta wel l Zo ne Vic

66 87 52

586 225 6

5 1. 3 7

14 .9 5

0. 1 8

9.6 0

0. 1 8

8. 9 8

1 2. 6 4

1. 36

0. 0 3

0. 0 5

Ou tcr op

Ande site

Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a

64 00 13

589 785 4

5 5. 8 5

16 .0 0

0. 4 7

8.4 6

0. 1 3

4. 9 8

1 0. 2 9

2. 48

0. 2 8

0. 0 9

5 7. 0 8

15 .5 5

1 1. 1 2

1. 57

Ou tcr op

Ande site

Ou tcr op

Ande site

Ou tcr op

Dacit e

Ou tcr op

Dacit e

64 00 13

589 785 4

0. 4 2

9.7 1

0. 1 1

3. 7 3

0. 0 9

0. 1 1

0. 8 4

0. 5 3

9 9. 3 4

0. 6 5

0 . 5 9

1 9

1 2

6 6

4 6 4

1 1

2 4 9

2. 0

0. 1

2. 0

1 2 4

2 1 8

1

0. 9

4 6 . 2

4 8

1 . 2

1 0 7 9

0 . 2

2 0 3

6. 9

5 6

9

9 9. 8 6

0. 5 4

0 . 6 9

1 0 0

2 0

3 8

1 2 8

1 6

2 3 4 1

5. 0

1. 9

8. 0

5 6

4 1 0

6

1 0. 2

2 9 . 8

2 0 8

4 . 0

2 8 1 7

0 . 0

2 9 7

1 7. 2

7 7

4 3

1 0 0. 0 1

0. 4 3

0 . 6 8

1 9

1 9

7 2 2

6. 0

2. 2

5. 0

2 5

4 7 1

1 4

1. 4

2 5 . 1

6 0

3 . 1

2 4 8 8

0 . 8

3 4 1

1 1. 9

8 9

5 2

64 00 13

589 785 4

5 9. 8 9

13 .0 6

0. 2 3

7.7 2

0. 1 2

6. 3 0

8. 5 6

2. 30

0. 5 2

0. 0 7

0. 8 6

9 9. 6 2

64 00 13

589 785 4

6 4. 4 0

13 .3 6

0. 3 9

6.9 6

0. 1 1

3. 2 4

5. 2 2

4. 33

0. 3 7

0. 1 0

0. 9 7

64 00 13

589 785 4

6 6. 4 2

13 .3 4

0. 4 4

7.9 3

0. 0 9

2. 3 0

3. 4 6

4. 52

0. 5 5

0. 1 1

0. 8 1

f o

2 3

l a

n r u 0. 6 2

0 . 6 6

1 0 5

9 9. 4 4

0. 4 8

0 . 7 9

9 9. 9 7

0. 3 6

0 . 9 3

o J

4 3

5 6

e

o r p

r P

1 7

4 1

2 7 3

1 3

4 3 4 1

5. 0

1. 3

3. 0

4 9

2 9 2

7

1 1. 9

3 2 . 2

1 9 8

4 . 1

1 3 7 3

0 . 9

2 0 4

6. 5

6 3

3 4

1 1 9

2 0

3 4

5 3

1 1

3 0 3 8

4. 0

2. 3

5. 0

2 0

4 2 8

8

6. 7

2 2 . 4

2 0 6

3 . 4

2 3 6 2

0 . 3

2 1 9

1 1. 6

7 2

5 3

7 0

2 1

5 8

6

1 4

4 5 3 2

5. 0

2. 4

7. 0

1 0

4 8 9

7

1 7. 6

2 1 . 5

1 5 7

5 . 3

2 6 1 3

1 . 9

2 8 2

1 4. 0

7 4

6 0

53

Journal Pre-proof MTS/ 5/02

VIC 31

VIC 55

VIC 23

VIC 45

Murr ay Drill Core Inter media te to Felsic Volca nics and Intrus ives MTR 13-04

Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria Mt Stav ely Belt Vol cani cs, W. Vict oria

Ou tcr op

Rhyo lite

Ou tcr op

Ande site

Ou tcr op

Ande site

Ou tcr op

Ande site

Inte rme diat e to felsi c

M TR 13

andes ite/rh yolite

Ou tcr op

Ande site

Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a Mt Sta vel y Bel t W. Vic tori a

64 00 13

589 785 4

7 5. 2 4

12 .5 1

0. 3 2

2.6 2

0. 0 4

0. 3 9

1. 1 6

5. 78

0. 5 4

0. 1 7

64 99 49

587 501 3

5 5. 2 0

14 .6 8

0. 6 1

9.0 5

0. 1 2

4. 3 2

8. 5 1

2. 37

1. 5 5

64 89 99

588 326 4

5 7. 8 9

12 .8 8

0. 4 7

8.5 6

0. 1 3

6. 5 3

6. 3 9

2. 47

1. 4 7

64 55 36

582 779 2

5 8. 4 2

14 .7 7

1. 4 9

6.6 3

0. 1 2

4. 7 0

6. 6 6

3. 80

0. 8 9

9 9. 1 6

0. 2 3

1 . 0 3

1 7 5

2 6

5 6

4

9

4 4 4 1

9. 0

2. 4

1 0. 0

2

7 5 5

8

1 1. 4

1 3 . 2

1 3 4

5 . 4

1 9 3 0

0 . 5

2 5

2 9. 7

5 4

5 6

0. 2 2

9 6. 6 3

0. 4 9

0 . 7 0

1 5 0

3 9

4 0

6 7

2 0

1 2 8 6 7

1 0. 0

1. 6

1 4. 0

1 4

9 6 0

4

3 0. 6

2 9 . 1

1 0 0

5 . 9

3 6 5 6

1 . 5

2 5 9

1 2. 5

7 0

8 2

0. 1 6

9 6. 9 5

0. 6 0

0 . 7 5

2 9 5

3 0

4 4

3 0 9

1 5

1 2 2 0 2

6. 0

0. 2

1 0. 0

6 4

6 9 8

4

3 8. 4

2 5 . 4

5 2 6

3 . 3

2 8 1 7

1 . 0

2 3 8

1 1. 0

6 6

7 0

2 1

7 3 8 8

1 1. 0

5. 7

2 0. 0

6 5

1 7 0 2

6

2 7. 3

1 9 . 3

4 2 5

2 . 5

8 9 3 1

1 . 3

1 6 7

2 1. 2

5 9

1 5 2

1 4

7 2 2 2

3. 0

0. 1

2. 0

4 8

3 0 5

5

2 6. 2

3 3 . 8

2 0 5

1 . 1

1 5 5 8

1 . 6

1 9 5

6. 2

5 6

3 8

1 4 7 3 0

1 4. 0

5. 9

1 7. 5

0

6 8 3

9

5 6. 1

1 6 . 4

8 . 4

3 1 2 8

5 . 2

1 7

2 6. 9

5 6

1 1 9

0. 3 9

0. 4 1

9 7. 8 7

63 95 98

589 757 3

6 0. 4 6

12 .6 4

0. 2 6

8.0 3

0. 1 3

6. 7 3

7. 4 6

1. 88

0. 8 7

0. 0 7

9 8. 5 3

39 05 21

601 747 7

6 8. 3 0

15 .1 0

0. 5 2

5.3 3

0. 1 0

0. 9 8

3. 7 0

4. 03

1. 7 7

0. 1 6

1 0 0. 0 0

0. 5 8

0 . 7 6

7 7

4 5

1 1 8

l a

n r u

o J

4 9

0. 6 2

0 . 7 2

1 3 2

1 8

4 1

2 7 4

0. 2 7

0 . 9 9

2 3 4

3 4

0

1

f o

o r p

e

r P

2

54

4 . 0

2 . 6

1 . 0

1 4

3 . 7

0 . 8

0 . 0

0 . 5

4 . 1

1 4 7

0 . 6 8

0. 4 0

2. 9 0

Journal Pre-proof

COP5 8-01

COP5 6-02

LD302

PAD D2801

Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es

C OP 58

diorit e

36 25 21

606 467 8

6 0. 1 0

14 .4 3

0. 9 1

10. 09

0. 2 2

5. 7 4

2. 3 1

1. 20

4. 7 4

0. 2 5

1 0 0. 0 0

0. 5 3

1 . 2 8

5 9 0

6 5

0

9 7

8

6 . 0

3 . 5

1 . 2

2 0

6 . 5

1 . 1

C OP 56

andes ite

36 62 91

609 810 8

6 2. 3 4

13 .0 4

2. 2 0

10. 88

0. 2 3

5. 1 7

1. 9 7

2. 78

1. 1 1

0. 2 8

1 0 0. 0 0

0. 4 8

1 . 3 9

2 8 6

3 3

0

1 3

1

7 . 5

5 . 0

1 . 3

1 7

6 . 5

1 . 6

L D3

diorit e

45 95 56

593 126 1

6 3. 7 6

17 .0 7

0. 6 3

5.4 3

0. 1 3

2. 0 2

5. 4 0

3. 16

2. 1 6

0. 2 2

1 0 0. 0 0

PA D D2 8

diorit e

44 32 01

600 867 6

5 7. 2 6

15 .3 1

1. 6 9

9.4 8

0. 1 8

3. 3 7

6. 4 1

3. 71

2. 2 5

0. 3 2

1 0 0. 0 0

o J

n r u

l a

0. 4 2

0 . 9 8

5 0 1

0. 4 1

0 . 7 6

4 7 9

3 9 3 8 0

3 0. 0

o r p

f o

0 . 0

0 . 5

1 5. 1

2 9. 0

4 8

1 0 9 4

1 7

1 3 6. 6

1 8 . 5

6 . 5

1 7 0

0 . 9 4

1 3 . 1

5 4 4 9

0. 5 0

5 . 8

1 9 4

3 6. 0

3. 4 0

1 2 4

1 7 9

9 2 2 0

1 2. 0

0 . 0

0 . 7

6. 2

1 7. 5

8

1 2 2 3

1 4

4 3. 0

3 2 . 4

4 . 9

1 3 5

1 . 1 0

6 . 0

1 3 1 9 1

0. 7 5

2 . 3

3 7 0

4 3. 0

5. 0 0

1 9 0

1 7 7

e

r P

4 6

0

6

3

3 . 0

1 . 6

1 . 2

1 8

3 . 2

0 . 5

1 7 9 6 1

2 2. 0

0 . 0

0 . 2

2 1. 4

2 0. 5

3

9 7 5

1 6

8 1. 2

9 . 1

4 . 0

3 7 8

0 . 5 6

7 . 2

3 7 7 5

0. 2 5

2 . 2

7 4

1 8. 2

1. 5 5

7 5

1 3 6

8 5

0

5

4

7 . 5

4 . 2

2 . 0

1 9

7 . 0

1 . 4

1 8 6 9 0

3 1. 0

0 . 0

0 . 5

1 5. 4

3 8. 5

6

1 4 1 6

3 7

9 8. 7

2 9 . 3

8 . 0

3 5 9

1 . 3 0

1 3 . 4

1 0 1 5 2

0. 5 5

2 . 3

2 2 5

4 2. 1

3. 7 0

1 8 1

2 1 2

55

Journal Pre-proof PAD D2805

PAD D2806

WYN 1-06

WYN 1-07

KMD -0701

Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in

PA D D2 8

diorit e

44 32 01

600 867 6

5 7. 7 1

15 .6 3

1. 9 6

9.3 2

0. 1 8

2. 5 2

5. 7 9

4. 08

2. 1 6

0. 6 4

1 0 0. 0 0

0. 3 5

0 . 8 0

4 7 7

1 1 0

0

0

4

9 . 5

5 . 0

2 . 7

2 1

9 . 0

1 . 7

1 7 9 7 1

4 6. 0

0 . 0

0 . 6

2 1. 6

5 5. 0

1

2 8 1 2

2 2

9 3. 6

2 6 . 3

1 1 . 0

4 5 9

1 . 6 0

1 3 . 7

1 1 7 6 9

0. 6 5

2 . 3

1 2 9

5 1. 8

4. 5 0

1 4 6

1 7 4

PA D D2 8

diorit e

44 32 01

600 867 6

5 8. 4 0

15 .5 8

1. 7 9

8.5 0

0. 1 6

2. 7 2

5. 7 3

4. 02

2. 6 4

0. 4 5

1 0 0. 0 0

0. 3 9

0 . 7 8

5 2 7

9 5

0

0

3

8 . 0

4 . 4

2 . 3

2 0

7 . 5

1 . 5

2 1 9 4 7

3 7. 0

0 . 0

0 . 6

1 9. 4

4 4. 5

3

1 9 4 5

3 1

1 0 7. 4

2 3 . 2

9 . 0

4 3 8

1 . 4 0

1 2 . 8

1 0 7 4 7

0. 6 0

3 . 8

1 6 6

4 5. 4

4. 0 0

1 3 9

1 3 7

f o

W Y N1

andes ite

40 24 21

609 227 8

6 4. 4 3

12 .7 6

1. 1 0

13. 01

0. 0 7

1. 4 4

1. 7 5

5. 07

0. 0 7

0. 2 8

1 0 0. 0 0

0. 1 8

1 . 1 0

2 6

3 6

0

1

l a

e

o r p

0

r P

1 0 . 5

7 . 0

1 . 8

1 9

7 . 5

2 . 1

5 8 9

1 1. 0

0 . 0

1 . 0

7. 3

2 3. 5

1

1 2 3 8

1

1. 3

1 6 . 3

7 . 0

1 1 3

1 . 6 5

4 . 7

6 6 1 8

0. 9 5

1 . 8

4 9

6 1. 9

6. 5 0

1 8

2 1 8

1 0 . 5

6 . 5

2 . 1

1 7

8 . 0

2 . 0

5 8 8

1 4. 0

0 . 0

0 . 9

7. 8

2 7. 0

0

9 7 1

1

1. 4

1 4 . 1

7 . 5

1 1 8

1 . 7 0

6 . 1

5 3 3 3

0. 9 0

1 . 6

3 6

6 4. 4

6. 5 0

1 2

2 4 3

4 . 2

2 . 8

1 . 2

2 1

4 . 3

0 . 9

1 5 1 0 8

2 4. 6

3 0 . 0

0 . 4

1 0. 3

2 1. 7

8 3

5 6 7

1 4

1 0 8. 0

1 6 . 0

4 . 4

2 7 6

0 . 6 9

9 . 7

4 1 9 6

0. 4 0

2 . 0

9 7

2 5. 0

2. 4 5

9 2

1 6 8

n r u

o J

W Y N1

andes ite

40 24 21

609 227 8

6 9. 6 8

11 .8 8

0. 8 9

9.5 2

0. 0 5

1. 0 6

1. 6 7

4. 95

0. 0 7

0. 2 2

K M D07

diorit e

37 96 14

604 109 6

5 5. 9 0

17 .7 7

0. 7 0

7.1 0

0. 1 1

6. 0 6

6. 0 8

3. 19

1. 8 2

0. 1 3

0. 9 4

1 0 0. 0 0

0. 1 8

1 . 0 6

2 8

4 4

0

2

0

9 9. 8 0

0. 6 3

0 . 9 7

3 0 3

5 0

5 4

1 8 0

9

56

2 5

5 . 8

Journal Pre-proof

KMD -0701

Padth away Ridge Atype Grani te JF07100

JF07102

JF07114b

JF07114a

JF07122

Mur ray Dril l Hol es Inte rme diat e to felsi c Roc ks in Mur ray Dril l Hol es

K M D07

diorit e

37 96 14

604 109 6

5 8. 3 2

16 .7 8

0. 2 0

1.9 6

0. 1 0

1. 5 2

4. 2 6

6. 02

3. 4 4

0. 0 3

6. 4 6

9 9. 0 9

0. 6 1

0 . 7 9

3 0 5

8 8

2 4

< 1 0

6

1 3 6

1 0 . 9

6 . 6

0 . 9

1 9

9 . 6

2 . 3

2 8 5 5 5

4 2. 1

1 0 . 0

1 . 0

2 1. 3

3 6. 4

4

1 3 1

1 0 1

1 0 . 1

1 6 2. 5

2 . 0

9 . 5

1 1 2

1 . 6 8

2 4 . 2

1 1 9 9

0. 9 9

4 . 2

9

6 6. 8

6. 4 2

1 6

2 0 3

f o

Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay

Ou tcr op

Grani te

Ou tcr op

Grani te

Col d and We t

38 69 64

604 414 8

7 4. 3 5

12 .3 2

0. 1 6

1.8 8

Col d and We t

38 69 64

604 414 8

7 3. 2 6

13 .0 8

0. 1 9

2.1 4

0. 0 4

0. 1 8

0. 8 1

3. 49

0. 0 5

0. 2 2

0. 8 5

3. 63

4. 8 4

0. 0 3

0. 2 9

9 8. 3 9

5. 1 9

0. 0 3

0. 2 9

9 8. 9 3

0. 1 6

0 . 9 9

3 8 4

1 0 7

l a

o J

n r u 0. 1 7

1 . 0 0

4 1 8

7 6

3

8

7

1 4 . 0

1 1 . 5

r P

e

o r p 1 . 0

1 7

1 0 . 0

3 . 3

4 0 1 7 7

5 8. 0

1 . 9

1 7. 1

4 4. 0

0

1 3 1

2 6

1 1 . 0

2 4 7. 6

4 . 5

8 . 5

3 6

2 . 0 0

4 0 . 0

9 5 9

1. 7 5

7 . 8

7

1 3 6. 2

1 2. 0 0

3 8

1 9 4

1 1 5

5 7

1

9

2

1 4 . 5

1 2 . 0

0 . 9

1 8

1 0 . 0

3 . 4

4 3 0 8 2

6 1. 0

2 . 0

1 8. 4

4 6. 0

0

1 3 1

3 0

1 0 . 5

2 6 2. 6

5 . 5

8 . 0

4 0

2 . 0 0

4 6 . 5

1 1 3 9

1. 8 0

8 . 7

9

1 4 8. 6

1 2. 5 0

4 1

2 1 1

Ou tcr op

Grani te

Ko nga l Ro cks

45 04 11

597 495 7

7 5. 1 9

11 .8 8

0. 0 7

6.4 6

0. 0 8

0. 0 6

0. 1 3

0. 34

3. 8 9

0. 0 1

1. 5 1

9 9. 6 2

0. 0 2

2 . 3 7

2 2

9 3

5 2

1

2 5

1

1 1 . 5

6 . 5

0 . 1

2 1

8 . 5

2 . 1

3 2 2 9 1

3 9. 0

1 . 1

3 8. 4

3 8. 0

0

4 4

9

1 1 . 0

6 1 6. 0

2 . 5

1 0 . 0

2

1 . 9 0

5 7 . 5

4 2 0

1. 0 0

1 3 . 9

2

9 6. 9

7. 5 0

4 0

1 1 5

Ou tcr op

Grani te

Ko nga l Ro cks

45 04 11

597 495 7

7 7. 0 2

12 .0 2

0. 0 6

1.5 2

0. 0 3

0. 0 4

0. 2 2

3. 24

4. 9 5

0. 0 1

0. 5 0

9 9. 6 1

0. 0 5

1 . 0 8

1 7

6 5

1 0 8

1

6

1

1 0 . 5

7 . 0

0 . 1

1 7

7 . 0

2 . 1

4 1 0 9 0

2 6. 0

1 . 3

3 4. 8

2 8. 0

0

4 4

2 6

8 . 0

4 4 0. 9

2 . 5

8 . 0

4

1 . 6 0

5 9 . 8

3 6 0

1. 1 5

1 7 . 9

3

7 5. 7

9. 0 0

1 3

1 4 2

Ou tcr op

Grani te

Jip Jip

42 71 39

596 157 2

7 4. 6 0

12 .7 0

0. 1 4

1.9 7

0. 0 5

0. 0 9

0. 8 5

4. 72

3. 0 4

0. 0 2

0. 4 1

9 8. 5 9

0. 0 8

1 . 0 1

4 2 0

9 6

5 2

1

1

1 2 . 5

8 . 5

1 . 8

2 5

9 . 5

2 . 7

2 5 2 3 5

4 5. 0

1 . 3

1 8. 5

5 2. 0

8 7

5

1 3 . 0

8 2. 0

1 1 . 5

5 8

2 . 0 0

1 5 . 5

8 0 9

1. 2 5

2 . 0

6 4. 0

9. 0 0

2 8

2 2 0

57

Journal Pre-proof

JF07108

JF07109

JF07116

JF07117

JF07119

KW0 8-1

KW0 8-15

PAD D32-

Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype Padt haw ay Rid ge Typ e Atype

Ou tcr op

Grani te

Mt Mo nst er

43 86 34

599 381 3

7 3. 7 1

13 .2 2

0. 1 8

1.9 7

0. 0 4

0. 2 3

0. 8 4

3. 55

5. 3 9

0. 0 3

0. 5 2

9 9. 6 8

0. 1 9

1 . 0 0

3 5 2

1 6 3

5 0

Ou tcr op

Grani te

Mt Mo nst er

43 86 34

599 381 3

7 3. 1 0

13 .1 0

0. 1 9

1.9 7

0. 0 4

0. 2 0

0. 8 5

3. 43

5. 4 0

0. 0 3

0. 6 6

9 8. 9 7

0. 1 7

1 . 0 1

3 3 0

1 6 0

4 8

Ou tcr op

Grani te

Ma rco llat

44 25 94

595 618 7

7 4. 4 2

12 .2 0

0. 1 9

2.5 3

0. 0 7

0. 0 8

0. 6 4

3. 66

5. 2 8

0. 0 2

0. 1 4

9 9. 2 3

0. 0 6

0 . 9 5

6 2

2 7 3

6 1

0. 0 4

0 . 9 5

8 0

Ou tcr op

Grani te

Ma rco llat

44 25 94

595 618 7

7 4. 5 0

12 .2 0

0. 2 0

2.4 5

Ou tcr op

0. 0 8

0. 0 5

0. 6 2

3. 63

Grani te

Ma rco llat

44 25 94

595 618 7

7 3. 8 0

12 .5 0

0. 1 7

Ou tcr op

Grani te

Sed an

34 91 49

618 251 8

7 4. 4 1

13 .2 3

Ou tcr op

Grani te

Mo ntei th

35 28 68

610 650 4

7 1. 4 5

PA D

Grani te

40 38

597 240

7 2.

5. 2 8

0. 0 2

0. 2 3

9 9. 2 6

2.0 4

0. 0 7

0. 0 4

0. 5 9

3. 69

5. 3 9

0. 0 2

0. 2 7

9 8. 5 8

0. 2 1

1.5 7

0. 0 4

0. 4 0

1. 2 7

3. 76

4. 2 6

0. 0 4

0. 2 8

13 .8 9

0. 3 7

1.9 7

0. 0 4

0. 4 5

0. 9 2

3. 90

5. 2 5

0. 1 0

0. 2 4

13 .9

0. 3

2.8 4

0. 0

0. 3

1. 2

2. 32

6. 7

0. 1

2 7 0

6 2

2

0

8 . 5

4 . 8

0 . 9

2 0

8 . 0

1 . 6

4 4 7 4 2

8 0. 0

0 . 7

2 4. 6

5 8. 0

4

3

9 . 0

5 . 5

1 . 0

2 4

8 . 5

1 . 9

4 4 8 2 5

8 2. 0

0 . 8

2 6. 0

6 4. 0

8 . 0

3 . 9

0 . 4

1 9

1 0 . 5

1 . 4

1

0 . 9 6

6 0

2 0 0

6 2

9 9. 4 7

0. 3 4

1 . 0 1

4 5 8

7 7

6 7

3

9 8. 5 8

0. 3 1

1 . 0 1

6 4 2

1 6 6

4 9

3

1 0

0. 2

1 .

8 7

2 0

0

3

1

1

2

2

1

6

58

9 . 0

4 . 5

2

7 . 0

3

8

4 3 8 2 9

1 4 9. 0

f o

0 . 6

2 4. 0

1 1 2. 0

o r p

e

r P

0. 0 4

o J

3

< 0 . 5

l a

n r u

4

0

1

1 3 1

1 5

1 7 . 5

1 8 4. 6

1 3 1

3 3

1 8 . 0

1 5 0. 0

8 7

1 4

2 8 . 0

1 0 7. 1

4 . 1

3 . 1

1 0 . 5

4 9

1 . 5 0

2 9 . 3

1 0 7 9

0. 6 5

6 . 0

1 1 . 0

5 0

1 . 5 0

2 8 . 5

1 1 3 9

0. 7 5

4 . 7

1 5 . 5

9

1 . 5 5

2 5 . 8

1 1 3 9

0. 5 5

5 . 5

7

4

5 0. 9

4. 8 0

2 6

2 3 0

4 4. 5

5. 5 0

4 0

2 2 0

4 2. 2

3. 9 0

5 7

4 0 8

0 . 5

2 4

1 1 . 0

1 . 7

4 3 8 2 9

1 5 0. 0

0 . 7

2 9. 5

1 1 5. 0

8 7

1 3

3 1 . 0

9 4. 0

1 7 . 0

1 0

1 . 6 5

2 4 . 5

1 1 9 9

0. 6 5

2 . 0

3 6. 0

4. 3 0

6 6

4 6 0

3 . 6

0 . 5

2 4

8 . 5

1 . 3

4 4 7 4 2

1 0 5. 0

0 . 5

2 3. 5

8 4. 0

8 7

1 4

2 3 . 0

1 0 0. 0

1 2 . 5

1 1

1 . 3 0

2 0 . 0

9 8 9

0. 5 0

2 . 2

2 9. 5

3. 5 0

5 4

3 9 0

4 . 9

3 . 2

0 . 8

1 7

4 . 3

1 . 0

3 5 3 6 2

4 1. 0

0 . 6

2 9. 0

2 3. 0

1

1 7 5

9

7 . 0

1 9 6. 5

3 . 9

4 . 8

9 4

3 3 . 4

1 2 5 9

0. 5 0

7 . 9

1 8

3 5. 1

3. 9 0

1 9

1 5 3

1 1 . 5

6 . 5

1 . 8

2 0

1 0 . 5

2 . 1

4 3 5 8 0

7 9. 0

0 . 8

4 3. 6

6 8. 0

1

4 3 6

1 3

1 5 . 5

1 4 1. 3

5 . 3

1 2 . 0

1 2 8

1 1 . 4

2 2 1 8

0. 9 5

1 . 2

2 1

7 3. 7

7. 0 0

3 7

2 7 3

6 .

2 .

0 .

2 0

1 1

0 .

5 5

6 8.

0 .

2 0.

8 0.

2

4 8

3 7

1 8

4 .

1 5

5 5

3 1

1 9

0. 2

4 .

1 4

3 2.

1. 4

5 0

2 5

0 .

< 0 . 2

< 0 . 2

1 .

Journal Pre-proof 04

IType Grani te Adela ide Hills A110 9-4

A110 9/13

BCv3 5

779/5 2

Padt haw ay Rid ge Typ e

D3 2

Itype Gra nite in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Itype Gra nite in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Itype Gra nite in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Itype Gra nite in Out crop

Ou tcr op

Grani te

Pt Elli ot

78

5

0 7

7

2

29 00 72

606 495 9

7 3. 2 8

13 .2 0

0. 3 3

2.2 5

4

7

0

0. 0 2

0. 7 4

1. 1 2

2. 62

4

1

5. 6 3

0. 0 8

0. 4 9

0. 0 0

1

0 5

6

5

9 9. 7 6

0. 3 9

1 . 0 6

5 0 8

7 7

7 4

1 3

5

0

1

9

6 . 9

3 . 7

0 . 8

1 8

. 5

9

9 7 3

0

7 . 2

1 . 2

4 6 7 3 5

4 0. 0

0

2

7

0

6

0 . 5

1 4. 8

3 2. 2

6

3 4 9

2 0

9. 4

8

. 0

9 . 8

3 3 0. 7

5 . 5

6 . 5

3 5

. 8

4 2

5

6

6 5

1 . 0 6

3 1 . 9

1 9 7 8

0. 4 5

2 . 6

8

0

6

3 1

4 6. 7

3. 1 0

1 3

1 4 8

4 9

2 2 0

f o

Ou tcr op

Grani te

An aba ma

42 36 36

637 696 8

6 5. 1 3

17 .2 8

0. 5 6

3.6 6

0. 0 5

1. 5 1

2. 9 3

3. 99

3. 7 7

0. 1 6

0. 8 0

9 9. 8 4

0. 4 5

1 . 0 8

1 3 4 6

9 5

7 9

2 1

l a

2 0 1

r P

e

o r p

5 . 1

2 . 6

1 . 4

2 2

5 . 8

0 . 9

3 1 2 9 5

5 0. 9

0 . 4

2 3. 3

3 6. 6

1 2

6 9 8

1 0

1 1 . 5

1 5 5. 3

7 . 6

6 . 3

4 0 4

0 . 8 0

2 2 . 0

3 3 5 7

0. 3 0

5 . 6

6 5

2 3. 9

2. 3 5

1 . 3 0

3 1 . 5

4 4 9 5

0. 4 5

5 . 2

9 5

4 3. 9

3. 1 0

3 2 0

3 . 0

4 0 1 6

0. 1 0

2 . 8

8 1

6. 0

0. 6 0

1 4 3

n r u

o J

Ou tcr op

Grani te

Vic tor Har bor

28 51 98

606 188 8

6 8. 7 0

14 .0 0

0. 7 5

4.3 3

0. 0 6

1. 5 9

2. 6 8

2. 85

4. 4 5

0. 1 5

Ou tcr op

Grani te

Re edy Ck

33 71 83

613 331 6

6 5. 6 0

16 .2 0

0. 6 7

4.5 7

0. 0 6

1. 7 7

3. 3 8

4. 36

2. 0 0

0. 2 4

1. 2 0

9 9. 5 6

0. 4 2

0 . 9 7

7 3 7

1 0 1

4 9

8 . 2

4 . 0

1 . 0

1 8

9 . 6

1 . 4

3 6 9 3 9

5 1. 5

0 . 5

1 7. 6

4 5. 9

8

6 5 5

1 4

1 2 . 9

2 1 5. 8

1 1 . 2

8 . 9

1 0 2

1 0 0. 0 5

0. 4 3

1 . 0 5

8 5 7

2 7

1 7

1 . 9

0 . 9

1 . 1

1 9

2 . 4

0 . 3

1 6 6 0 2

1 5. 2

0 . 1

1 3. 0

1 1. 6

1 9

1 0 4 7

8

3 . 1

9 2. 0

1 0 . 0

2 . 1

5 1 8

59

Journal Pre-proof

R14 L1

R154 L75

R99 L248

Kinch ina Quarr y High SiO2 Adaki te CG 18 12

Ade laid e Hill s/ Fleu rieu r/ KI Itype Gra nite in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Itype Gra nite in Out crop Ade laid e Hill s/ Fleu rieu r/ KI Itype Gra nite in Out crop Ade laid e Hill s/ Fleu rieu r/ KI

Ada kite s (Mo

Ou tcr op

Grani te

Ta nun da

31 62 38

617 533 1

7 0. 4 9

13 .4 6

0. 6 8

3.9 4

0. 0 4

1. 1 5

2. 7 3

2. 99

3. 3 8

0. 1 3

0. 4 6

9 9. 4 5

0. 3 7

0 . 9 9

9 2 2

6 8

5 4

1 0

3 0

Ou tcr op

Grani te

Ta nun da

31 62 38

617 533 1

7 6. 7 5

11 .9 4

0. 2 8

1.6 9

0. 0 1

0. 3 3

0. 7 0

3. 72

3. 6 7

0. 0 3

0. 1 8

9 9. 3 1

0. 2 8

1 . 0 5

5 7 4

9 5

6 8

3

1 8

o J

Ou tcr op

Grani te

Ta nun da

31 62 38

617 533 1

7 1. 5 9

13 .6 3

0. 6 8

2.5 2

0. 0 1

0. 6 1

1. 1 9

4. 60

3. 2 8

0. 1 2

1. 5 1

9 9. 7 5

Ou tcr op

Adak itic Grani te

Kin chi na Qu

33 70 07

611 350 2

7 1. 6 2

15 .1 0

0. 2 6

1.9 7

0. 0 2

0. 5 2

1. 9 1

4. 27

3. 4 2

0. 0 9

0. 2 8

9 9. 4 6

2 8 0 8 2

r P

0. 3 2

1 . 0 3

5 0 5

9 4

8 7

7

0. 3 4

1 . 0 6

2 2 8 0

1 8 1

7 2

< 1 0

3 6

1

60

5

3 1. 0

1 5. 7

3 1. 0

7

5 7 2

3

1 2 1. 7

9 . 0

1 2 3

1 2 . 1

4 0 7 6

2 . 2

6 2

4 6. 4

3 0

2 8 5

f o

o r p 1 7

e

l a

n r u

1 9

2 4

1 . 1

0 . 5

1 . 1

1 8

2 . 2

0 . 2

3 0 4 9 8

4 8. 0

2 1. 6

3 4. 0

2

1 4 0

3

1 4 4. 3

3 . 6

4 5

4 0 . 6

1 6 7 8

8 . 2

1 2

4 0. 1

4

2 6 9

2 7 2 6 0

3 8. 0

2 4. 6

4 3. 0

5

5 4 1

3

6 2. 7

1 1 . 8

1 0 9

2 2 . 7

4 0 7 6

2 . 9

3 9

4 4. 4

7

3 5 8

2 8 3 8

1 2 4. 0

1 0. 0

4 2. 7

< 2

3 8 0

1 4

7 9. 8

2 . 0

6 3 . 8

1 5 5 8

2 4

3 2 0

0 . 1

1 5 . 0

4 . 5

5 8 0

0 . 2 4

0. 0 5

3 . 3

4. 7

0. 5 5

Journal Pre-proof

CG 18 6

CG 18 24

CG 18 18

CG 18 19

nart o/ Kin chin a) Ada kite s (Mo nart o/ Kin chin a) Ada kite s (Mo nart o/ Kin chin a) Ada kite s (Mo nart o/ Kin chin a) Ada kite s (Mo nart o/ Kin chin a)

arr y

9

Ou tcr op

Adak itic Grani te

Kin chi na Qu arr y

33 70 07

611 350 2

7 1. 8 2

15 .1 0

0. 2 5

2.0 9

0. 0 2

0. 5 2

1. 7 9

4. 13

3. 3 4

0. 0 8

0. 2 9

9 9. 4 3

0. 3 3

1 . 1 1

2 3 4 0

1 8 3

6 0

< 1 0

1

4

1 . 1

0 . 5

1 . 1

1 9

2 . 4

0 . 2

2 7 7 2 5

1 2 9. 0

0 . 1

8. 0

4 4. 8

< 2

3 5 0

1 5

1 5 . 3

8 3. 0

2 . 0

4 . 7

5 7 0

0 . 2 4

6 6 . 9

1 4 9 8

0. 0 5

3 . 3

2 0

4. 7

0. 5 0

2 8

2 8 0

Ou tcr op

Adak itic Grani te

Kin chi na Qu arr y

33 70 07

611 350 2

7 3. 1 2

14 .4 0

0. 2 8

1.6 2

0. 0 2

0. 5 7

1. 6 9

4. 73

2. 3 5

0. 0 7

0. 4 7

9 9. 3 2

0. 4 1

1 . 0 7

1 6 0 0

1 0 0

6 8

< 1 0

1

7

1 . 2

0 . 7

0 . 9

1 8

2 . 0

0 . 2

1 9 5 0 7

6 5. 5

0 . 1

9. 5

2 6. 3

< 2

3 2 0

1 7

8 . 7

6 1. 0

2 . 0

3 . 4

5 0 0

0 . 2 2

6 4 . 1

1 6 7 8

0. 1 0

3 . 4

2 0

5. 7

0. 7 5

2 4

2 8 0

Ou tcr op

Adak itic Grani te

Kin chi na Qu arr y

33 70 07

611 350 2

7 2. 6 7

14 .8 0

0. 2 2

1.6 9

0. 0 2

0. 4 4

1. 7 2

4. 37

3. 0 2

0. 1 2

0. 3 4

9 9. 4 1

0. 3 4

1 . 0 9

2 2 5 0

1 2 3

6 7

< 1 0

1

1 8

1 . 4

0 . 8

1 . 0

1 7

2 . 0

0 . 3

f o

Ou tcr op

Grani te

Kin chi na Qu arr y

33 70 07

611 350 2

7 7. 0 6

14 .1 0

0. 0 2

0.2 6

0. 0 1

0. 1 6

2. 5 8

4. 86

0. 4 9

0. 0 7

0. 3 6

9 9. 9 7

0. 5 5

1 . 0 7

1 3 0

7

5 4

0 . 5

1 4

0 . 6

0 . 1

l a

< 1 0

n r u

o J

Note: Table S1 in supplementary data contains a full listing of whole rock analyses.

e

r P 1

61

4

o r p

0 . 5

0 . 3

2 5 0 6 9

8 2. 9

0 . 1

1 3. 5

3 0. 9

< 2

5 3 0

1 3

1 0 . 3

7 0. 4

2 . 0

3 . 6

5 2 0

0 . 2 4

4 3 . 0

1 3 1 9

0. 1 0

2 . 7

3 0

6. 4

0. 7 0

1 8

1 8 0

4 0 6 7

4. 3

0 . 0

< 0. 5

3. 0

< 2

3 0 0

6

0 . 8

1 9. 4

< 1

0 . 7

2 8 0

0 . 0 8

1 . 6

1 2 0

< 0. 0 5

0 . 4

2 0

2. 3

0. 2 5

1 0

1 0

Journal Pre-proof

Table 5. Nd- and Sr- isotopic Compositions of Delamerian Samples Ma gma Sa tic mp Suit Loc le e ality No. E N Syn-tectonic I-type Granite

31 61 86

617 540 8

Grani te Defo rmed Grani te Defo rmed

32 .2 3

7. 38

0.512 177

0. 50 0

39 .1 8

7. 57

0.511 801

0. 50 0

68 .2 9

11 .8 8

0.512 045

0. 50 0

13 2. 62

25 .9 4

0.512 128

0. 50 0

33 .3 8

7. 27

0.512 228

0. 50 0

33 .8 4

6. 48

0.512 209

0. 50 0

47 .8 9

9. 62

0.512 224

0. 50 0

24 .4 0

3. 94

0.511 614

0. 50 0

40 .2 9

7. 68

47

0.2 29

0.139

1. 21

1. 84

0.117

1. 59

2. 01

9. 00 16 .3 3

26

0.1 93

0.105

0. 99

0.118

0. 99

 N ( d G (0 a) )

Nd/ 144 Nd( T)

N d( T)

r/86 Sr

± S R (2 r b sig p p R m p p b/ a) m m Sr

0.51172 3

5.2 9

0.73 094

12

12 5

12 1

0.9 68

2.80 6

0.710 95

0.51141 8

11. 24

0.72 916

14

16 9

99

0.5 83

1.68 9

0.717 12

1. 46

11 .5 8

0.51170 0

5.7 4

0.75 449

15

75

14 5

1.9 26

5.59 7

0.714 61

1. 53

9. 95

0.51174 0

4.9 5

0.84 694

15

34

22 5

6.6 30

19.4 43

0.708 40

143

87

S

87

R b/86 Sr

87

Sr/ Sr( T)

86

Grani te 31 61 86

617 540 8

Defo rmed

17

0.1 74

23

0.1 96

45

0.2 18

36

0.1 92

31 61 86

617 540 8

R15 L85 eh5 R15 4 L75 eh8 R16 5 L76 eh7

31 61 86

617 540 8

31 61 86

617 540 8

31 61 86

617 540 8

R24 L38 eh1 R99 L24 8 eh6

31 61 86

617 540 8

31 61 86

617 540 8

Defo rmed Grani te Defo rmed Grani te Defo rmed Grani te Defo rmed Grani te Defo rmed Grani te Defo rmed

0.512 207

Cold and Wet

JF0 7 100

38 69 64

604 414 8

Unde form ed

Grani te

0. 48 5

42 .3 5

8. 52

0.512 340

Cold and Wet Kong al Rock s

JF0 7 102 JF0 7 114 b

38 69 64

604 414 8

Unde form ed

Grani te

0. 48 5

42 .5 5

8. 63

0.512 342

45 04 11

597 495 7

Unde form ed

Grani te

0. 48 5

51 .3 4

9. 32

0.512 300

Jip Jip Kong al Rock s Murr ay Drill Core

JF0 7 122 JF0 7 114 a PA DD 324

42 71 39

596 157 2

Unde form ed

Grani te

0. 48 5

48 .6 7

10 .3 4

0.512 458

45 04 11

597 495 7

Unde form ed

Grani te

0. 48 5

27 .2 4

6. 98

0.512 370

40 38 78

597 240 5

Unde form ed

Grani te

0. 48 5

81 .6 6

13 .6 8

0.511 983

Mt Mons ter

JF0 7 109

43 86 34

599 381 3

Unde form ed

Grani te

0. 48 5

61 .6 3

10 .5 0

0.512 238

Mt Mons ter

JF0 7 108

43 86 34

599 381 3

Unde form ed

Grani te

0. 48 5

61 .6 0

10 .1 7

0.512 233

Marc olat Marc

JF0 7 117 JF0

44 25 94 44

595 618 7 595

Unde form ed Unde

Grani te Grani

0. 48 5 0.

99 .9 3 11

14 .6 5 15

0.512 152 0.512

pr oo f

Grani te

Post-tectonic A-type Granite Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te A-

0. 50 0

0.132

0. 96

1. 59

7. 99

0.51179 7

3.8 4

0.71 090

14

24 0

2

0.0 08

0.02 4

0.710 72

0.116

0. 81

1. 37

8. 38

0.51182 9

3.2 2

0.77 243

14

47

14 4

3.0 75

8.95 4

0.708 64

0.121

0. 84

1. 43

0.51182 6

3.2 8

0.78 573

17

46

17 2

3.7 05

10.8 00

0.708 77

0.098

1. 57

1. 92

8. 08 19 .9 7

0.51129 4

13. 67

0.72 348

13

29 5

10 6

0.3 58

1.03 9

0.716 08

0.115

0. 81

1. 37

8. 41

0.51182 9

3.2 2

0.72 679

12

11 1

62

0.5 58

1.61 7

0.715 26

0.122

0. 61

1. 33

5. 82

0.51195 3

1.1 7

0.83 136

15

36

22 0

6.1 80

18.0 96

0.706 31

0.123

0. 61

1. 34

5. 77

0.51195 2

1.1 9

0.82 866

13

26 3

36

0.1 37

0.40 1

0.825 89

0.110

0. 59

1. 24

6. 60

0.51195 1

1.2 1

5.01 182

42

3

49 5

15 0

617

0.749 79

0.128

0. 40

1. 22

3. 51

0.51205 0

0.7 2

0.73 725

15

58

82

1.4 14

4.10 2

0.708 90

0.155

0. 98

1. 99

0.51187 8

2.6 4

2.28 266

24

6

36 5

66

222

0.751 30

0.101

1. 05

1. 57

5. 23 12 .7 7

0.51166 1

6.8 7

0.78 732

15

55

18 9

3.4 56

10.0 78

0.717 68

0.103

0. 65

1. 25

7. 80

0.51191 1

2.0 0

0.77 477

15

50

15 0

3.0 30

8.82 5

0.713 78

0.100

0. 64

1. 22

7. 90

0.51191 6

1.9 1

0.77 879

14

48

18 5

3.8 86

11.3 22

0.700 54

0.089 0.084

0. 69 0.

1. 21 1.

9. 47 -

0.51187 1 0.51190

2.7 8 -

0.88 594 0.89

15 15

10 9

94 10

9.8 95 12.

29.1 27 36.6

0.684 65 0.638

e-

Tanu nda Grani te Tanu nda Grani te Tanu nda Grani te Tanu nda Grani te Tanu nda Grani te

617 540 8

42

0.2 01

50

0.1 62

20

0.1 91

11

0.2 01

11

0.2 03

9

0.1 81

22

0.2 12

9

0.2 56

9

0.1 68

17

0.1 70

10

0.1 65

12 16

0.1 47 0.1

Pr

Tanu nda Grani te

31 61 86

N

T D M

± (2 147 sig S S m m/ m/144 a) Nd Nd

al

Itype grani te Itype grani te Itype grani te Itype grani te Itype grani te Itype grani te

R14 L1 eh1 0 R14 L1 K eh2 R14 7A L47 5 eh1 1 R14 8 L47 7 eh9

d/144 Nd

143

rn

Itype grani te

Tanu nda Grani te Tanu nda Grani te Tanu nda Grani te

S m p p m

Jo u

Itype grani te Itype grani te

Roc kTyp e

A g N e d ( p G p a) m

T C h ur ( G a)

62

Journal Pre-proof olat

7 116

25 94

618 7

form ed

Marc olat

JF0 7 119

44 25 94

595 618 7

Unde form ed

Derg holm

Der ghol m

51 92 18

586 371 6

Mont eith

KW 0815

35 28 68

Mont eith Seis mogr aph rocks

F06 09

te

48 5

2. 00

.5 0

175

38

63

14

Grani te

0. 48 5

81 .5 1

Unde form ed

Grani te

0. 48 5

610 650 4

Unde form ed

Grani te

35 28 68

610 650 4

Unde form ed

SEI S20 00

43 95 03

596 997 8

Man num

MG 1

34 94 48

Man num

MG 3

Seda n

Seda n

11 .8 8

0.512 159

22

0.1 46

0.088

0. 67

1. 19

9. 34

0.51187 9

2.6 2

0.90 370

15

32 .7 6

5. 93

0.512 218

24

0.1 81

0.109

0. 73

1. 28

8. 19

0.51187 0

2.7 9

0.79 988

0. 48 5

68 .0 0

12 .0 0

0.512 256

15

0.1 76

0.107

0. 65

1. 26

7. 45

0.51191 7

1.8 8

Grani te

0. 48 5

69 .2 9

12 .8 0

0.512 231

12

0.1 85

0.112

0. 73

1. 36

7. 94

0.51187 6

Unde form ed

Grani te

0. 48 5

60 .6 0

11 .6 9

0.512 171

25

0.1 93

0.117

0. 89

1. 44

9. 11

613 761 6

Unde form ed

Grani te

0. 48 5

61 .8 8

10 .6 0

0.512 267

24

0.1 71

0.104

0. 61

1. 21

34 94 48

613 761 6

Unde form ed

Grani te

0. 48 5

53 .2 8

9. 33

0.512 325

20

0.1 75

0.106

0. 53

1. 09

SG1

34 91 49

618 251 8

Unde form ed

Grani te

0. 48 5

24 .0 1

4. 60

0.512 282

20

0.1 92

KW 081

34 91 49

618 251 8

Unde form ed

Grani te

0. 48 5

23 .0 0

4. 80

0.512 346

21

0.2 09

618 251 8

Unde form ed

Syn Atype mafic

Man num Dyke

MG 7

34 94 48

613 761 6

Unde form ed

KW 087

34 94 48

613 761 6

Unde form ed

F06 07

35 28 68

610 650 4

Unde form ed

F06 06

35 28 68

610 650 4

Unde form ed

Syn Atype mafic Syn Atype mafic Syn Atype mafic

Man num Taile m Bend gabbr o Taile m Bend gabbr o

0. 48 5

25 9. 71

48 .0 7

0.512 302

0. 48 5

26 .6 0

5. 94

0.512 534

0. 48 5

15 .8 9

3. 38

0.512 396

0. 48 5

20 .7 0

4. 68

0.512 682

0. 48 5

19 .2 4

4. 26

0.512 645

10

0.1 85

31

0.2 23

10

0.2 12

20

0.2 26

18

0.2 21

12

0.1 05

11

0.1 09

10

0.2 10

2.0 3

183

7

45 3

80

34

11

10 0

9.0 91

26.8 07

0.718 44

15

23 0

48

0.2 07

0.60 6

0.795 69

0.72 873

15

12 8

14 1

1.1 01

3.19 3

0.706 67

2.6 8

0.73 365

15

10 4

14 3

1.3 83

4.01 0

0.705 94

0.51180 0

4.1 6

0.77 248

20

19 2

57

0.2 96

0.86 3

0.766 52

7. 24

0.51193 8

1.4 7

0.71 990

15

17 8

12 7

0.7 13

2.06 7

0.705 62

6. 11

0.51198 8

0.4 8

0.73 230

20

13 1

17 9

1.3 65

3.96 0

0.704 93

0.116

1. 26

6. 94

0.51191 4

1.9 4

0.74 431

21

10 0

20 0

1.9 97

5.79 9

0.704 24

0.126

0. 63

1. 39

5. 70

0.51194 5

1.3 3

0.74 643

15

94

19 7

2.0 97

6.09 0

0.704 34

0.112

0. 61

1. 26

6. 56

0.51194 6

1.3 1

0.72 856

14

15 0

18 5

1.2 33

3.57 6

0.703 85

0.135

0. 26

1. 18

2. 03

0.51210 5

1.7 9

0.70 563

12

39 7

25

0.0 63

0.18 2

0.704 37

0.129

0. 54

1. 34

4. 73

0.51198 7

0.5 0

0.70 533

14

42 8

25

0.0 57

0.16 6

0.704 19

0.137

0. 11

0. 92

0. 86

0.51224 7

4.5 7

0.70 588

15

56 4

18

0.0 32

0.09 1

0.705 25

0.134

0. 02

0. 95

0. 15

0.51222 0

4.0 5

0.70 527

15

77 4

13

0.0 16

0.04 7

0.704 95

0.064

0. 39

0. 79

6. 66

0.51209 0

1.7 5

0.70 720

5

57 0

83

0.1 46

0.42 1

0.704 23

0.066

0. 40

0. 80

0.51207 8

1.5 2

0.70 714

5

58 0

80

0.1 38

0.39 8

0.704 33

0.127

1. 56

1. 91

6. 75 13 .9 0

0.51151 3

9.5 2

0.71 297

5

28 0

19

0.0 69

0.20 1

0.711 56

0.108

1. 68

1. 94

19 .2 1

0.51130 5

13. 58

0.75 319

5

13 0

16 2

1.2 46

3.62 1

0.727 65

0.134

0. 66

1. 48

5. 32

0.51192 7

1.3 0

0.71 333

13

14 7

56

0.3 82

1.10 6

0.705 45

Pr

34 91 49

al

KW 082

rn

Seda n

Sub alkali c doleri te Sub alkali c doleri te Sub alkali c doleri te Sub alkali c doleri te Sub alkali c doleri te

Jo u

Syn Atype mafic

9

0. 67

e-

Post-tectonic mafic magmas co-magmatic with A-type Granite

9. 03

pr oo f

type grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te Atype grani te

Syn-tectonic Adakite and associated crustal melt Adak ite

Adak ite

Leuc o Kan mant oo Mig matit ie

Kinc hina Quar ry Kinc hina Quar ry Kinc hina Quar ry

Kinc hina Quar ry

CG 186

33 70 07

611 350 2

Defo rmed

Tron djemi te

0. 49 5

38 .7 7

4. 08

0.512 296

CG 1812

33 70 07

611 350 2

Defo rmed

Tron djemi te

0. 49 5

37 .4 9

4. 08

0.512 292

CG 1819

33 70 07

611 350 2

Defo rmed

Leuc ogran ite

0. 49 5

2. 37

0. 50

0.511 925

CG 185

33 70 07

611 350 2

Defo rmed

Mig matit e

0. 49 5

38 .6 8

6. 88

0.511 653

12

0.1 78

8

0.2 21

Murray Drill Hole Intermediate to Felsic Samples (not A-type) Defo rmed

Murr ay Drill Core

MT R13 -4

39 05 21

601 747 7

Defo rmed

Dacit e

0. 50 0

18 .1 3

4. 01

0.512 365

63

Defo rmed

Defo rmed

Defo rmed Unde form ed Unde form ed Unde form ed

Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core

CO P58 -01

36 25 21

606 467 8

Defo rmed

CO P56 -02

36 62 91

609 810 8

45 95 56

LD 3-2 PA DD 2801 PA DD 2805 PA DD 286

Ande site

0. 51 0

28 .8 2

5. 81

0.511 939

Defo rmed

Dacit e

0. 47 5

17 .2 7

4. 37

0.512 481

593 126 1

Defo rmed

Diori te

0. 50 0

21 .1 2

3. 95

0.512 211

44 32 01

600 867 6

Unde form ed

Diori te

0. 47 5

36 .6 8

7. 51

0.512 317

44 32 01

600 867 6

Unde form ed

Diori te

0. 47 5

53 .6 0

10 .3 0

0.512 288

44 32 01

600 867 6

Unde form ed

Diori te

0. 50 0

42 .5 5

8. 42

0.512 306

0.122

1. 43

1. 99

13 .6 4

0.153

0. 55

1. 65

3. 07

0.51200 5

0.4 1

0.71 339

13

13 5

43

0.3 19

0.92 4

0.707 13

0.113

0. 78

1. 41

8. 32

0.51184 1

2.9 9

0.71 152

14

37 8

81

0.2 15

0.62 2

0.707 09

0.124

0. 67

1. 40

6. 27

0.51193 2

1.8 4

0.71 104

11

35 9

99

0.2 75

0.79 7

0.705 65

0.116

0. 67

1. 34

6. 84

0.51192 6

1.9 6

0.70 966

11

45 9

94

0.2 04

0.59 0

0.705 67

0.120

0. 66

1. 36

6. 47

0.51191 4

1.5 6

0.71 036

13

43 8

10 7

0.2 45

0.71 0

0.705 30

0.128

1. 10

1. 77

0.51171 4

5.2 1

0.71 233

13

16 6

61

0.3 69

1.07 0

0.704 55

0.126

1. 13

1. 78

9. 67 10 .2 0

0.51169 3

5.6 2

0.71 319

15

15 7

54

0.3 42

0.99 0

0.705 99

0.106

0. 71

1. 31

8. 14

0.51189 0

2.6 7

0.70 719

14

61 2

60

0.0 99

0.28 5

0.705 26

e-

Journal Pre-proof

0. 62

1. 33

6. 08

0.51195 2

1.4 4

0.71 319

12

63 8

24 2

0.3 80

1.09 9

0.705 75

0.2 14

0.129

0. 08

0. 98

0. 73

0.51216 9

3.6 7

0.70 498

11

65 3

17

0.0 26

0.07 5

0.704 44

0.130

0. 07

0. 98

0. 57

0.51217 4

3.7 8

0.70 909

12

20 9

51

0.2 44

0.70 5

0.703 96

0.124

0. 15

0. 98

1. 37

0.51218 3

3.0 7

0.70 772

15

15 1

20

0.1 32

0.38 1

0.705 14

0.133

0. 10

0. 88

0. 79

0.51226 6

4.6 9

0.70 959

14

30 8

59

0.1 92

0.55 6

0.705 83

0.179

0. 05

1. 96

0. 12

0.51203 4

1.0 4

0.70 947

18

90

20

0.2 19

0.63 4

0.704 87

0.171

1. 28

2. 33

4. 26

0.51184 9

2.5 8

0.70 865

10

10 7

11

0.1 00

0.29 1

0.706 53

0.175

0. 39

1. 36

1. 09

0.51212 7

2.4 8

0.71 044

12

24 0

21

0.0 86

0.24 8

0.708 69

0.176

0. 84

1. 21

2. 19

0.51217 9

3.4 9

0.71 104

15

23 0

37

0.1 60

0.46 3

0.707 78

0.161

0. 42

1. 75

1. 89

0.51200 2

0.4 1

0.70 781

11

26 4

25

0.0 96

0.27 9

0.705 79

0.165

0. 35

1. 80

1. 40

0.51201 4

0.6 5

0.70 903

12

14 9

28

0.1 86

0.53 7

0.705 12

0.150 0.154

0. 45 0.

1. 53 1.

2. 73 -

0.51199 8 0.51201

0.3 4 0.6

0.71 223 0.71

13 12

10 9 17

33 64

0.3 04 0.3

0.88 0 1.09

0.705 83 0.705

13

0.2 02

8

0.2 53

9

0.1 87

8

0.2 05

9

0.1 92

9

0.1 98

10

0.2 12

9

0.2 09

9

0.1 76

0.1 99

0.51153 1

8.7 8

0.73 129

13

17 0

13 7

0.8 04

2.33 2

0.714 34

KT H12 -02

43 67 71

596 917 7

Defo rmed

Boni nite

0. 51 0

15 .2 4

3. 23

0.512 142

KT H12 -01

43 67 71

596 917 7

Defo rmed

Boni nite

0. 51 0

12 .9 5

2. 71

0.512 115

0. 47 5

43 .7 1

7. 69

0.512 221

0. 47 5

38 .2 5

7. 60

0.512 326

11

0. 51 0

29 .6 4

6. 34

0.512 601

0. 51 0

38 .9 4

8. 38

0.512 609

0. 47 5

40 .0 1

8. 18

0.512 568

0. 47 5

32 .8 8

7. 21

0.512 679

0. 51 0

8. 72

2. 58

0.512 632

0. 51 0

8. 46

2. 39

0.512 420

0. 49 5

23 .8 4

6. 89

0.512 694

0. 49 5

19 .7 1

5. 74

0.512 750

0. 51 0

17 .3 0

4. 62

0.512 541

0. 51 0

17 .5 8

4. 80

0.512 566

0. 51 0 0.

10 .0 5 12

2. 48 3.

0.512 498 0.512

Murray Drill Core Alkali Basalt 606 477 8

Defo rmed

MT R10 -01 PA DD 3108 PA DD 3104 PA DD 3105 PA DD 3304

39 98 63

598 527 8

Defo rmed

43 32 41

598 857 8

Unde form ed

43 32 41

598 857 8

Unde form ed

43 32 41

598 857 8

Unde form ed

40 31 96

598 526 9

weak ly Def

Alkal i Basal t Alkal i Basal t Alkal i Basal t Alkal i Basal t Alkal i Basal t Alkal i Basal t

10

al

36 84 53

rn

CO P55 -01

Jo u

Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core

9

0.2 15

9

0.2 05

10

0.2 19

33

0.2 96

53

0.2 82

11

0.2 89

11

0.2 91

11

0.2 67

8

0.2 73

9 12

0.2 47 0.2

pr oo f

Murr ay Drill Core Murr ay Drill Core

Pr

High Mg Andesite- Boninite

0.120

Tholeiitic Basalt and Dolerite Tanu nda gabbr o Tanu nda gabbr o Kinc hina Quar ry Kinc hina Quar ry Murr ay Drill Core Murr ay Drill Core Murr ay Drill Core Murr

R16 4 L75 eh3 R17 7 L48 3 eh4

31 61 86

617 540 8

Thole iite Defo rmed Thole iite

31 61 86

617 540 8

CG 1811

33 70 07

611 350 2

CG 1829

33 70 07

611 350 2

MT R12 -01

39 28 21

601 747 7

MT R12 -02

39 28 21

601 747 7

MT R12 -04 MT

39 28 21 39

601 747 7 601

Defo rmed Thole iite Defo rmed Thole iite Defo rmed Thole iite Defo rmed Thole iite Defo rmed Thole iite Defo rmed Defo

Thole

64

Journal Pre-proof ay Drill Core Murr ay Drill Core

R12 -03

28 21

747 7

rmed

WY N101

40 24 21

609 227 8

Unde form ed

iite

Thole iite

51 0

.0 0

0. 51 0

14 .7 0

06

526

55

40

57

2. 18

2

0

347

4. 49

0.512 894

12

0.3 06

0.185

3. 37

1. 32

4. 98

0.51227 6

5.7 6

0.70 984

19

0.4 33

0.262

1. 11

0. 11

9. 33

0.51225 8

5.1 6

0.70 449

13

0.4 34

0.263

1. 12

0. 09

9. 43

0.51226 1

5.2 3

0.70 352

11

0.2 44

0.147

0. 96

1. 86

6. 06

0.51184 4

2.9 2

0.70 792

16

0.2 44

0.147

0. 99

1. 89

6. 25

0.51183 4

3.1 1

9

0.2 64

0.160

1. 38

2. 35

6. 47

0.51178 3

12

0.2 35

0.2 46

0

78

5

51

21 1

32

0.1 50

0.43 5

0.706 68

59

1

0.0 08

0.02 5

0.704 31

48

1

0.0 19

0.05 4

0.703 14

11

15 7

18

0.1 12

0.32 5

0.705 60

0.70 785

13

19 8

12

0.0 60

0.17 4

0.706 61

4.1 2

0.70 711

16

20 8

10

0.0 49

0.14 2

0.706 10

12

Mt Stavely Volcanic Suite and Magdala Basalt, W. Victoria 586 225 6

Defo rmed

Boni nite

0. 50 0

0. 86

0. 37

0.513 116

66 87 52

586 225 6

Defo rmed

Boni nite

0. 50 0

0. 78

0. 34

0.513 122

MT S1

64 00 13

589 785 4

Defo rmed

Dacit e

0. 50 0

9. 09

2. 22

0.512 327

MT S2

64 00 13

589 785 4

Defo rmed

Ande site

0. 50 0

4. 20

1. 02

0.512 317

MT S3

64 00 13

589 785 4

Defo rmed

Ande site

0. 50 0

7. 37

1. 95

0.512 307

MT S4

64 00 13

589 785 4

Defo rmed

Ande site

0. 50 0

7. 30

1. 72

0.512 237

MT S5

64 00 13

589 785 4

Defo rmed

Rhyo lite

0. 50 0

11 .4 6

2. 82

0.512 316

9

MT S6

64 00 13

589 785 4

Defo rmed

Rhyo lite

0. 50 0

8. 14

1. 91

0.512 244

JF0 9 VIC 23

64 55 36

582 779 2

Defo rmed

Ande site

0. 50 0

21 .8 1

4. 95

0.512 546

JF0 9 VIC 31

64 99 49

587 501 3

Defo rmed

Ande site

0. 50 0

16 .3 3

3. 29

0.512 368

JF0 9 VIC 45

63 95 98

589 757 3

Defo rmed

Ande site

0. 50 0

4. 74

1. 20

0.512 346

JF0 9 VIC 55

64 89 99

588 326 4

Defo rmed

Ande site

0. 50 0

12 .8 7

2. 70

0.512 348

rn

11

0.2 27

9

0.2 01

12

0.2 52

7

0.2 10

65

13

1. 92

7. 82

0.51177 1

4.3 6

0.70 730

12

20 6

7

0.0 33

0.09 4

0.706 63

1. 03

1. 94

6. 28

0.51182 8

3.2 4

0.70 831

14

13 4

11

0.0 85

0.24 6

0.706 55

0.142

1. 09

1. 89

7. 68

0.51178 0

4.1 7

0.70 732

12

60

1

0.0 23

0.06 7

0.706 84

0.137

0. 24

1. 19

1. 79

0.51209 7

2.0 1

0.70 650

42 5

27

0.0 64

0.18 6

0.705 17

0.122

0. 55

1. 28

5. 27

0.51196 9

0.4 8

0.71 013

10 0

31

0.3 08

0.89 0

0.703 79

0.153

1. 01

1. 98

5. 69

0.51184 6

2.8 8

0.70 807

20 5

26

0.1 28

0.37 1

0.705 43

0.127

0. 64

1. 39

5. 66

0.51193 2

1.2 1

0.70 597

52 6

38

0.0 73

0.21 1

0.704 46

0.142

e-

0.2 34

16

1. 13

0.149

al

13

pr oo f

66 87 52

Pr

JF0 9 VIC 02 JF0 9 VIC 07

Jo u

Mag dala Basal t Mag dala Basal t Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics Mt Stave ly Volc anics

11

11

12

14

Journal Pre-proof Declaration of interests

Jo

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-p

ro

of

☒ The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

66

Journal Pre-proof Graphical abstract

Jo

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of

Highlights  Establishment of subduction in the early Cambrian Between Australian sector of Gondwana  Early subduction produces volcanic arc in eastern South Australia in late Early Cambrian  Early production of boninite  Mid to Late Cambrian history of back-arc extension and MORB-like magmatism in eastern South Australia  Arc moves to Mt Stavely belt W. Victoria by 510Ma  Delamerian Oorgeny terminated by delamination and slab break-off to produce adakite and Atype granite

67

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20