Detrital fingerprint: The use of early Precambrian zircon age spectra as unique identifiers of Phanerozoic terranes

Earth and Planetary Science Letters 506 (2019) 97–103

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Detrital fingerprint: The use of early Precambrian zircon age spectra as unique identifiers of Phanerozoic terranes Uri Shaanan a,b , Gideon Rosenbaum a , Matthew J. Campbell a a b

School of Earth and Environmental Sciences, The University of Queensland, Brisbane, Australia Institute of Earth Sciences, Hebrew University of Jerusalem, Givat Ram, Israel

a r t i c l e

i n f o

Article history: Received 6 May 2018 Received in revised form 26 October 2018 Accepted 28 October 2018 Available online xxxx Editor: A. Yin Keywords: detrital fingerprint terrane analysis zircon provenance paleodrainage New Caledonia

a b s t r a c t Archean and Proterozoic zircon grains are commonly found in much younger clastic sedimentary rocks, but the geological significance of these ages is often overlooked. Here we demonstrate that the age spectra of early Precambrian sedimentary recycled and/or magmatic inherited zircon grains form a unique pattern (detrital fingerprint) that can be used to test connectivity or indicate sediment recycling between terranes. Using the island of New Caledonia as a case study, we compiled 212 (published and new) concordant ages that are older than 1400 Ma from samples that represent contemporary sediments (this study), an allochthonous nappe sequence, and Paleozoic–Mesozoic metasedimentary rocks. By comparing these data with an equivalent dataset of Precambrian zircon ages (n > 1400 Ma = 2636) from Paleozoic eastern Australia (Tasmanides), we test connectivity and disjunction of New Caledonia with crustal domains within the Tasmanides. Results show that the early Precambrian detrital fingerprint of New Caledonia is similar to the southern Tasmanides (and possibly East Antarctica), but is significantly different than the detrital fingerprint of the northern Tasmanides. The results thus provide an independent constraint on the origin of the late Paleozoic to early Mesozoic New Caledonian continental basement, shedding new light on the tectonic evolution of the southwestern Pacific region, and demonstrate the capabilities of the methodological approach. © 2018 Elsevier B.V. All rights reserved.

1. Introduction Zircon is resistant to physical and chemical weathering and its U–Pb isotopic chronometers are highly resilient. Therefore, Precambrian ages of zircon grains commonly occur in much younger Phanerozoic clastic sedimentary rocks (e.g., Fedo et al., 2003; Gehrels, 2014). Clusters of zircon ages record periods of magmatism and crustal growth (e.g., Condie et al., 2009; Belousova et al., 2010), but these ages may be preferentially preserved and biased by sedimentary and tectonothermal processes (Carson et al., 2002; Cawood et al., 2003, 2012). The determination of prominent detrital zircon age populations is commonly used in provenance studies (Vermeesch, 2004; Andersen, 2005), but the geological significance of Precambrian ages that are found in much younger sedimentary rocks is commonly not explored. Such ages may record prolonged histories of sedimentary recycling, metamorphic growth and/or magmatic inheritance. The distribution of early Precambrian ages may have been affected by age-modifying processes (i.e., open system behavior and/or Pb mobilization), and does not necessarily involve prominent clusters of age populations; nevertheless, equiv-

E-mail address: [email protected] (U. Shaanan). https://doi.org/10.1016/j.epsl.2018.10.039 0012-821X/© 2018 Elsevier B.V. All rights reserved.

alent age spectra may represent characteristic grain assemblages that experienced similar transportation and post-deposition history. In this work we show that early Precambrian detrital zircon ages from different Phanerozoic tectonic entities (i.e., crustal domains, basin sequences, and drainage systems) form an insightful spectrum of ages that is characteristic of each entity, thus defining a unique identifier of Phanerozoic terranes (hereinafter detrital fingerprint). Using data from eastern Australia and the southwestern Pacific region, we explain how to define and validate characteristic early Precambrian age spectra of different Phanerozoic tectonic entities. We further demonstrate how such age spectra can be used to determine connectivity and sediment recycling between terranes. The Paleozoic crustal domains of eastern Australia and the southwestern Pacific region are dominated by subduction-related rock units that formed along the convergent margins of eastern Gondwana (Fig. 1; Cawood, 2005; Rosenbaum, 2018). These rocks typically include a significant component of recycled sediments (Fergusson et al., 2017; Shaanan et al., in press). The Cretaceous to Cenozoic opening of the Tasman and Coral seas (Fig. 1B, Gaina et al., 1998, 1999) led to dispersal of continental fragments throughout the southwest Pacific region (Schellart et al., 2006;

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Matthews et al., 2015). Earlier (Paleozoic and early Mesozoic) tectonic reconstructions remain poorly constrained. 2. Methodological approach 2.1. Determination of a characteristic age spectrum

Fig. 1. A. The study area. B. Land topography and ocean bathymetry of eastern Australia and the southwest Pacific region. White dashed arrows denote the proposed/permissible path of New Caledonia and the gray polygon denotes the postulated location of New Caledonia at 80 Ma relative to Australia (after Seton et al., 2012; Matthews et al., 2015). A white star denotes the location of the early Permian rock units (Nambucca Slate, Kempsey beds, and Dyamberin beds). C. Simplified tectonostratigraphic map of New Caledonia showing the locations of alluvial samples (this study) and rock samples (Adams et al., 2009; Cluzel et al., 2011; Pirard and Spandler, 2017; Campbell et al., 2018). Abbreviations: Cre-Eoc – Late Cretaceous to early Eocene, M – Mossman domain, NAC – North Australian Craton, NE – New England domain, QP – Queensland Plateau.

Seton et al., 2012; Matthews et al., 2015), but there is evidence that continental fragmentation had already commenced earlier, in the course of an early Permian phase of extension that was likely driven by subduction rollback (Cawood, 1984; Korsch et al., 2009b; Shaanan et al., 2015). One such rifted continental fragment is the continental basement of New Caledonia (Fig. 1B, Cawood, 1984; Cluzel et al., 2010, 2011; Campbell et al., 2018), but kinematic information on the dispersal of this continental domain is relatively scarce and limited to the latest Cretaceous and Cenozoic times (e.g., Cande et al., 2000; Schellart et al., 2006; Seton et al., 2012;

Determination of prominent detrital zircon age components from a clastic sedimentary sample is commonly perceived as statistically adequate if several dozens to about a hundred concordant ages are obtained (Vermeesch, 2004; Andersen, 2005, and references therein). A greater number of ages provides higher confidence that all meaningful age populations are represented in the data. Regardless of the required number of analyses for a sample to be considered statistically adequate, natural variations in the proportions of age populations occur even between successive beds of coherent successions (Fig. 2A; Shaanan and Rosenbaum, 2018; Shaanan et al., in press) and along drainage pathways (Cawood et al., 2003; Sharman and Johnstone, 2017; Ibañez-Mejia et al., 2018). Therefore, in order to determine the characteristic age spectrum of a given tectonic entity, and to account for internal heterogeneity of the age spectra, one must examine multiple statistically adequate samples that are spatially distributed. An example for a varying proportion of age populations in multiple genetically-related samples (from the New England Orogen, eastern Australia; Fig. 1) is presented in Fig. 2B–F. The example shows that samples from three early Permian rock units of a once contiguous rift-related basin (n = 1325, Fig. 2C–E) consist of large variations in the proportions of similar age populations. The age populations of these samples are intermitted by similar intervals of absence of zircon ages at 1500–1300 Ma and 850–650 Ma (Fig. 2B, F). The combined datasets (i.e., data from two or more related samples that are used together as a group) of the three early Permian rock units (n = 1325) show that these units consist of similar age populations in resembling proportions. Furthermore, the fact that the age spectra of early Permian rocks are similar to the age spectrum of Paleozoic (meta)sedimentary rocks from the encompassing orogenic belt (n = 1710, black stroke in Fig. 2B) indicates that these age populations and proportions are characteristic of the orogenic belt. The required number of samples, their distribution in space and time, and the quantity of total grain analyses for the determination of the characteristic age spectrum of a given tectonic entity, largely depend on the geological context and research questions (e.g., Ibañez-Mejia et al., 2018). In the New England Orogen, age spectra from different samples of early Permian basin sequences are consistent with each other and with a larger dataset of their encompassing orogenic belt (Fig. 2B). Similarly, here we show that early Precambrian age spectra from basement rocks (37 samples, n > 1400, Ma = 117) in New Caledonia (Figs. 1, 3) provide a characteristic detrital fingerprint, and we demonstrate repeatability with and within alluvial samples from across the island (Figs. 3B, 4; nine samples, n > 1400, Ma = 55). The number of analyses and the spatial distribution of the samples within the terrane determine the ability to recognize and validate the significance of subtle patterns in the age spectra. The validity of the age spectra of specific intervals (e.g., early Precambrian) can be determined by (1) demonstrating repeatability, and/or (2) meeting the number of ages that must be produced to achieve a statistical adequacy of an individual provenance sample (e.g., Vermeesch, 2004; Andersen, 2005). While we cannot provide a numeric threshold for the number of samples or analyses, we demonstrate the application using datasets that differ by an order of magnitude (i.e., from n = 342 to n = 3831). The larger datasets allow us to establish regional tectonic constraints, whereas the smaller dataset is used to test repeatability of the >1400 Ma age spectra.

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2.2. Comparison of geochronological datasets Once detrital zircon datasets are constructed, it is possible to assess genetic relationships between different tectonic entities, such as derivation from a common source or recycling (correspondence). Datasets that represent common provenance are expected to comprise equivalent age populations, as well as corresponding intervals of absence of ages (e.g., Fig. 2B, F). The nonparametric two-sample Kolmogorov–Smirnov test is commonly used to quantify dissimilarity in the age spectra of different provenance samples (e.g., Vermeesch, 2018, and references therein). This test determines the difference between two samples as the maximum distance between their cumulative distributions along the Y -axis (D-value, Fig. 2G, H). However, the Kolmogorov–Smirnov test does not account for natural variations in the proportions of ages and thus quantifies such variations as a difference (e.g., Saylor et al., 2013; Ibañez-Mejia et al., 2018; Shaanan and Rosenbaum, 2018; Vermeesch, 2018). For example, samples that consist of similar age populations in varying proportions (e.g., green and blue curves in Fig. 2G, H) are classified as unrelated to each other. Conversely, two distinctly different sets of ages with resembling slope (blue and red curves in Fig. 2G, H) seem highly similar. High variations in the proportion of age populations are expected in sedimentary systems that receive detritus from several different source regions and/or drainage systems (e.g., Fig. 2A). Therefore, for the study of bimodal or polymodal basins, such as backarc basins, where continental interior and arc-derived sediments are mixed (Cawood et al., 2012) in varying proportions (in space and time), the Kolmogorov–Smirnov test may not be suitable. Alternatively, as shown in Fig. 4, the comparison and possible relationships between geochronological datasets can be considered based on the correspondence of age populations and intermitting time intervals (absence of zircon ages), and not on the basis of variation in the proportion of age populations. 2.3. Examination of selected intervals

Fig. 2. Examples of the effect of sediment mixing on proportional variations in age populations. A. Block diagram showing a bimodal basin infill. Note that the mixing ratio would vary in space and time. Also shown are schematic columnar sections, circle charts, and distribution function plots for age populations. B–E. Cumulative proportion curves of detrital zircon U–Pb ages from samples (thin lines) and datasets (thick lines) of early Permian siliciclastic units (Nambucca Slate, Kempsey beds, and Dyamberin beds) from the New England domain (eastern Australia), and equivalent data from other Devonian–Permian metasedimentary successions throughout the whole New England domain. F. Distribution of detrital ages from the New England domain. G. Synthetic cumulative proportion curves showing two samples of similar ages in different proportions (green and blue). The curves appear dissimilar to each other, but two samples (blue and red) that do not have overlapping ages appear similar to each other. H. Three representative samples from the Nambucca Slate that demonstrate the relationships illustrated in G. The red sample is synthetic and was generated by artificially shifting all (measured) ages of a corresponding sample to be 50 Myr older. Data sources: Adams et al., 2013; Shaanan et al., 2015, in press; Shaanan and Rosenbaum, 2018, and references therein.

Age spectra are commonly presented in relative probability plots (Dodson et al., 1988; Sircombe, 2004), kernel density estimation plots (Sircombe and Hazelton, 2004), and/or cumulative proportion curves (e.g., Cawood et al., 2012). In these distribution functions, the Y -axis is normalized, so subtle patterns and subpopulations are commonly obscured by the dominant age components. For example, mixing of recycled sediments with younger more prominent age components would hinder the recognition of the original proportion of the recycled detritus. An individual sample of a Phanerozoic clastic sedimentary rock would typically contain only a few Archean and/or Proterozoic zircon grains. While these cannot support a meaningful interpretation, datasets from multiple samples may reveal clusters of early Precambrian ages. This can be done by normalizing separate intervals from the datasets (e.g., Fig. 3B). For example, Ordovician clastic sedimentary rock, which was derived from a combination of Precambrian siliciclastic basement and Cambrian igneous rocks, may provide detrital zircon data that can be split into two datasets. While Cambrian ages are sourced from the Cambrian igneous rocks, the majority of Precambrian ages would likely correspond to the characteristic ages of the Precambrian basement. Dissecting the age spectra into intervals enables to examine and compare age populations with specific possible sources or correlative successions (e.g., Shaanan and Rosenbaum, 2018; Shaanan et al., 2018, in press). Cut-off points for dissection of the age spectra into intervals are best placed in periods of absence (or low abundance) of ages. Such periods appear on a cumulative proportion curve as horizontal

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Fig. 3. Detrital zircon geochronological data from the Tasmanides and New Caledonia. A. Cumulative proportion curves. B. Cumulative proportion curves for ages older than 1400 Ma. C. Kernel density estimates. Data sources: Adams et al. (2009), Cluzel et al. (2011), Pirard and Spandler (2017), Shaanan et al. (in press, and references therein), Campbell et al. (2018), and this study (see Fig. 4).

(flat) sections, and as troughs (lows) on the kernel density estimation plot. For example, the two most prominent detrital age populations in Paleozoic rocks from eastern Australia are 1300–900 Ma and 600–500 Ma (Figs. 3A, C), so the cut-off point for a separate examination of these populations can be positioned in the intermitting time span. Whether the cut-off is set at 900 or 700 Ma does not significantly influence the results, as ages within this interval are relatively scarce. 2.4. Detrital fingerprint Age calculation of the U–Th–Pb series commonly yields discordant data (when 206 Pb/238 U, 207 Pb/235 U, 208 Pb/232 Th, and 207 Pb/ 206 Pb present inconsistent ages) as a result of Pb loss during later geological events or long-term Pb mobilization (Mezger and Krogstad, 1997). Such open-system or diffusive behaviors are commonly plotted in concordia diagrams (e.g., 206 Pb/238 U versus 207 Pb/235 U) as discordia lines. Accepted concordance for the inclusion of analyses in a dataset is subjective and is typically under 10% discordance (Sircombe, 2004; Nemchin and Cawood, 2005). Nevertheless, the use of ratios between different chronometers for assessment of data reliability (i.e., concordance) results in higher tolerance for data of earlier geological time (Nemchin and Cawood, 2005). For example, while <10% discordance of Late Cretaceous ages (100–66 Ma) are under ±10 Myr, that of Archean ages (4000–2500 Ma) can be up to ±400 Myr. Further-

more, high uranium content and prolonged tectonothermal histories make Precambrian grains more prone and likely to undergo age-modifying processes associated with an open-system behavior and/or intra-grain Pb mobilization (Mezger and Krogstad, 1997; Carson et al., 2002; Kusiak et al., 2013; Gehrels, 2014; Ge et al., 2018). Such processes may result in apparent ages of unclear geological significance. While some of the Precambrian ages found in younger sedimentary rocks may not be geologically meaningful, it is expected that different geological entities would have characteristic detrital fingerprints that reflect the history of sediment recycling and/or magmatic inheritance processes, as well as differences in thectonothermal histories. An examination of the detrital fingerprint requires that the selected cut-off age predates tectonic events that may have disrupted the continuity of corresponding terranes or basin sequences, while including a sufficient number of ages within the dissected time span. The fact that older grains are more prone to have isotopic compositions that were modified by tectonic events makes the age spectra of early intervals most likely to be influenced by the tectonothermal history of the terrane. Therefore, while agemodifying events may lead to geologically meaningless ages (i.e., ages that do not necessarily correspond to geological ‘events’), the effect of age-modifying processes can contribute to the development of a unique spectrum of ages that is characteristic to rocks that were deposited together and shared the same tectonic history.

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Fig. 4. Detrital zircon geochronological data from alluvial samples (New Caledonia). A. Cumulative proportion curves. B. Cumulative proportion curves for split (and separately normalized) intervals (<350 Ma, 500–700 Ma, 700–1200 Ma, excluding samples with n < 20). C. Kernel density estimates (excluding samples with n < 50) and distribution of all detrital ages.

3. Southwest pacific case study New Caledonia is made of late Paleozoic to early Mesozoic continental terranes (Téremba, Koh-Central, and Boghen, Fig. 1C) that are unconformably overlain by a Late Cretaceous and Cenozoic sedimentary and ophiolitic nappe sequence (Cluzel et al., 2012). Sedimentary rocks from the ophiolitic nappe sequence are suggested to consist of first-cycle relatively young (Cretaceous to Eocene) detritus that is mixed with recycled detritus from the underlying late Paleozoic to early Mesozoic terranes (Cluzel et al., 2011; Pirard and Spandler, 2017). The Paleozoic to early Mesozoic terranes consist of terrigenous rocks with a detrital input from Precambrian and early Paleozoic continental Gondwana (Adams et al., 2009; Cluzel et al., 2010; Campbell et al., 2018). 3.1. Detrital fingerprints of the Tasmanides The Tasmanides have traditionally been subdivided into five orogenic belts (hereinafter domains) that generally become younger from west to east (Rosenbaum, 2018). Remarkable consistency in detrital zircon data from the Delamerian and Thomson domains suggests that they are the southern and northern segments, respectively, of a single tectonic entity (Fig. 3A, Shaanan et al., in press), which also includes the Ross Orogen in Antarctica (Fig. 5, Flöttmann et al., 1993). The New England domain, although representing the youngest component of the Tasmanides, is the least recycled; over 80% of the detrital ages in the New England domain proximate the time of deposition, thus indicating first-cycle

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Fig. 5. Pre-Permian schematic plate reconstruction of the southwest Pacific region (after Cande et al., 2000; Seton et al., 2012; Matthews et al., 2015) showing the suggested source region of the New Caledonian proto-basement (black ellipse). The position of New Caledonia at 80 Ma (relative to Australia), and its present-day position, are also shown (gray and black polygons, respectively). Gray dashed arrows denote a permissible path for New Caledonia in respect to Australia. Abbreviations: D-T – Delamerian–Thomson domain, L – Lachlan domain, M – Mossman domain, NC – New Caledonia, NE – New England domain.

sediments (Fig. 3A). However, the >1400 Ma age spectrum of the late Paleozoic New England domain suggests that detritus was also sourced from the early Paleozoic Delamerian–Thomson domain (Fig. 3B, Shaanan et al., in press). In contrast, data from the Mossman and Lachlan domains, and specifically their >1400 Ma age spectra, significantly differ from data of the Delamerian–Thomson and New England domains (Fig. 3A, B). Thus, within the >1400 Ma age spectra of the Tasmanides, three distinct end-members are recognized: (1) the Delamerian–Thomson and New England domains; (2) Mossman domain; and (3) Lachlan domain. These three endmembers occupy different sections of eastern Australia (Fig. 1B), so the recognition of these end-members in age spectra of formerly contiguous segments of eastern Gondwana, such as New Caledonia, can indicate their origin in respect to the different domains. 3.2. Data acquisition and results Samples of riverbed and coastal sand from a wide area throughout New Caledonia (Fig. 1C) were stepwise crushed and sieved through a 425 μm mesh to ensure sufficient fragmentation. Clay and other light and magnetic minerals were extracted using a Wilfley shaker table and a Frantz magnetic separator. Heavy minerals (>3.32 g/cm3 ) were separated using a Diiodomethane heavy liquid in a tapped funnel. Zircon grains were handpicked, mounted in nonreactive epoxy, polished to expose their inner sections, and imaged both optically (Leica DM6000 M) and with an electron microscope (Zeiss Sigma FE SEM) in order to allocate ablation sites for analyses. Isotopic compositions were obtained using an Agilent 8800 laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS). Temora 2 (Black et al., 2004) and Plešovice (Sláma et al., 2008) zircon grains and NIST 610 glass (Pearce et al., 1997) were used as primary, monitor and trace elements reference mate-

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rials, respectively. Data reduction was conducted using Iolite software (Paton et al., 2011). Age calculation and data visualization were produced using DensityPlotter (Vermeesch, 2012) and Isoplot (Ludwig, 2003) software (for further details see Supplemental Material). A total of 1890 analyses of alluvial zircon grains from nine samples from New Caledonia (Fig. 1C) yielded 868 concordant ages (discordance <10%), of which 55 analyses from five samples yielded concordant ages that are older than 1400 Ma (Figs. 3, 4, and Supplemental Material). The youngest alluvial concordant zircon dates are 42 ± 11 and 42 ± 15 Ma; these ages overlap within 2σ error with a cluster of Paleogene ages that culminate at c. 60 Ma (Fig. 3C). The 60 Ma age population is dominant in one sample (146_SH_NC) and is absent in the other samples, suggesting derivation from a proximal source of limited dispersion (Fig. 4). The second and third youngest age populations are c. 120 and c. 230 Ma (Early Cretaceous and Triassic), whereas two prominent older age populations are c. 550 Ma and c. 930 Ma (Figs. 3C, 4C). The high resemblance (overlapping lines) of the separately normalized intervals (Fig. 4B) and consistency of population estimates and intermitting intervals (Fig. 4C), suggest that the variation between the full age spectra of the samples (Fig. 4A) results from differences in the proportion of similar age populations (i.e., provenance). The indication of representation of similar provenance in the different samples implies that the samples are suitable to be examined and used together as a dataset. Our new data were examined together with 3120 concordant U–Pb ages (n > 1400, Ma = 117) from late Paleozoic to early Mesozoic rocks from New Caledonia (Fig. 3B, after Adams et al., 2009; Cluzel et al., 2011; Campbell et al., 2018), and 9628 concordant U–Pb ages from the Tasmanides (Shaanan et al., in press, and references therein). Ages older than 1400 Ma on a cumulative proportion curve (Fig. 3B) show that the New Caledonian age spectra from both alluvium and metasedimentary rocks (172 ages) are consistent with each other and with the flattening and steepening of the age spectra of the Delamerian–Thomson/New England and in somewhat lesser degree, with the Lachlan domains (end-members 1 and 3). However, they do not correspond to the age spectrum of the Mossman domain (end-member 2), which has a unique prominent age population of c. 1550 Ma that is absent from all other datasets. An equivalent dataset of Late Cretaceous to early Eocene metasedimentary sequence from northern New Caledonia (Pirard and Spandler, 2017) includes of a lower number of >1400 Ma ages (n = 40), which also seem to correspond with the age spectra of the Delamerian–Thomson/New England domains (Fig. 3B). 3.3. Tectonic implications The detrital zircon age spectra from New Caledonia, and specifically, the occurrence of prominent c. 550 Ma and c. 930 Ma age populations are characteristic for the Tasmanides (e.g., Fergusson et al., 2017; Shaanan et al., in press). Within the Tasmanides, the age population of c. 1550 Ma is prominent only in the Mossman domain (Shaanan et al., in press), and occurs as a minor constituent in the New England domain (Korsch et al., 2009a) and its inferred northern continuation (Queensland Plateau, Fig. 1B; Shaanan et al., 2018). The correlation of the >1400 Ma age spectra of New Caledonia with the detrital fingerprints of the Delamerian–Thomson/New England domains, in conjunction with the absence of the c. 1550 Ma (end-member 2, Mossman domain) and c. 320 Ma (New England domain) age populations (Fig. 3), suggest recycling of detritus from Delamerian–Thomson (and possibly Lachlan) early Paleozoic successions into late Paleozoic and early Mesozoic New Caledonia. Disjunction with the Mossman (absence of the ∼1550 Ma age population) and New England (absence of

the ∼320 Ma age population) domains, in conjunction with evidence for recycled detritus of the Delamerian–Thomson and possibly Lachlan domain(s), indicate that the crustal basement of New Caledonia was derived from southeastern Australia or East Antarctica (Fig. 5). Late Paleozoic sediment dispersal from the Delamerian–Thomson domain toward the paleo-Pacific margins of eastern Gondwana has previously been suggested (Shaanan et al., in press). However, our results for the detrital fingerprint of New Caledonian cannot be explained by direct drainage of the Ross–Delamerian–Thomson domain through the Lachlan domain, as New Caledonia was situated at an isolated intra-oceanic island arc setting during the Mesozoic (Adams et al., 2009; Campbell et al., 2018), and its basement appears to have been rifted from eastern Gondwana during the early Permian (Campbell et al., 2018). This implies that the recycling of early Paleozoic Thomson–Delamerian detritus into late Paleozoic and Mesozoic New Caledonia was not direct. An intermitted cycle of pre-Permian deposition and post-rift erosion and reworking may explain the New Caledonian detrital fingerprint. An alternative possibility is that a rifted segment of the Ross–Delamerian–Thomson domain constitutes an older unexposed basement of New Caledonia and that this early Paleozoic segment was subsequently locally reworked. The c. 930 Ma age population recognized in the alluvium (Figs. 3C, 4C) may be the recycled expression of the prominent age population of such a proto-basement. Regardless of the exact source of the New Caledonian detritus (i.e., reworking of a rifted early Paleozoic New Caledonian proto-basement block or pre-Permian drainage and sediment recycling), the detrital fingerprints of New Caledonian rock units and alluvium suggest disjunction from the northern Tasmanides and an origin proximal to southeastern Australia (Figs. 1B, 5). 4. Conclusions Early Precambrian ages from Phanerozoic clastic rocks provide a characteristic detrital fingerprint that can be used to assess correspondences between terranes. The propensity of Precambrian zircon grains to undergo modification of isotopic ratios (due to a relatively high uranium content and prolonged recycling/inheritance histories) means that the geological significance of individual Precambrian U–Pb ages is commonly ambiguous. However, the early Precambrian age spectra, even if affected by age-modifying processes, can be used for terrane analysis, because such modifications further distinguish between terranes that underwent different tectonic histories. Based on detrital zircon datasets from the Tasmanides and New Caledonia, we demonstrate connectivity of the latter with the southern Tasmanides (and possibly East Antarctica) and disjunction from the northern Tasmanides. Examinations of early intervals, in conjunction with the overall age spectra, indicate that detritus from the early Paleozoic Delamerian–Thomson rocks was recycled in the New England domain (Shaanan et al., in press) and New Caledonia (this study). The approach, as demonstrated on Paleozoic terranes using Archean–Mesoproterozoic ages, can possibly be used also for younger intervals (e.g., using Paleozoic ages for analysis of Cenozoic terranes). In addition to providing constraints on tectonic reconstructions, a similar approach can be used to correlate basins and to better understand sediment dispersal systems and crustal evolution. Acknowledgements Dominique Cluzel and Pierre Maurizot are acknowledged for their assistance in the field.

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Appendix A. Supplementary material Supplementary material related to this article can be found online at https://doi.org/10.1016/j.epsl.2018.10.039. References Adams, C.J., Cluzel, D., Griffin, W.L., 2009. Detrital-zircon ages and geochemistry of sedimentary rocks in basement Mesozoic terranes and their cover rocks in New Caledonia, and provenances at the eastern Gondwanaland margin. Aust. J. Earth Sci. 56, 1023–1047. Adams, C.J., Korsch, R.J., Griffin, W.L., 2013. Provenance comparisons between the Nambucca Block, eastern Australia and the Torlesse Composite Terrane, New Zealand: connections and implications from detrital zircon age patterns. Aust. J. Earth Sci. 60, 241–253. Andersen, T., 2005. Detrital zircons as tracers of sedimentary provenance: limiting conditions from statistics and numerical simulation. Chem. Geol. 216, 249–270. Belousova, E.A., Kostitsyn, Y.A., Griffin, W.L., Begg, G.C., O’Reilly, S.Y., Pearson, N.J., 2010. The growth of the continental crust: constraints from zircon Hf-isotope data. Lithos 119, 457–466. Black, L.P., Kamo, S.L., Allen, C.M., Davis, D.W., Aleinikoff, J.N., Valley, J.W., Mundil, R., Campbell, I.H., Korsch, R.J., Williams, I.S., Foudoulis, C., 2004. Improved 206 Pb/238 U microprobe geochronology by the monitoring of a trace-elementrelated matrix effect; SHRIMP, ID–TIMS, ELA–ICP–MS and oxygen isotope documentation for a series of zircon standards. Chem. Geol. 205, 115–140. Campbell, M.J., Shaanan, U., Rosenbaum, G., Allen, C.M., Cluzel, D., Maurizot, P., 2018. Permian rifting and isolation of New Caledonia: evidence from detrital zircon geochronology. Gondwana Res. 60, 54–68. Cande, S.C., Stock, J.M., Muller, R.D., Ishihara, T., 2000. Cenozoic motion between East and West Antarctica. Nature 404, 145–150. Carson, C.J., Ague, J.J., Grove, M., Coath, C.D., Harrison, T.M., 2002. U–Pb isotopic behaviour of zircon during upper-amphibolite facies fluid infiltration in the Napier Complex, east Antarctica. Earth Planet. Sci. Lett. 199, 287–310. Cawood, P.A., 1984. The development of the SW Pacific margin of Gondwana – correlations between the Rangitata and New England orogens. Tectonics 3, 539–553. Cawood, P.A., 2005. Terra Australis Orogen: Rodinia breakup and development of the Pacific and Iapetus margins of Gondwana during the Neoproterozoic and Paleozoic. Earth-Sci. Rev. 69, 249–279. Cawood, P.A., Nemchin, A.A., Freeman, M., Sircombe, K., 2003. Linking source and sedimentary basin: detrital zircon record of sediment flux along a modern river system and implications for provenance studies. Earth Planet. Sci. Lett. 210, 259–268. Cawood, P.A., Hawkesworth, C.J., Dhuime, B., 2012. Detrital zircon record and tectonic setting. Geology 40, 875–878. Cluzel, D., Adams, C.J., Meffre, S., Campbell, H., Maurizot, P., 2010. Discovery of Early Cretaceous rocks in New Caledonia: new geochemical and U–Pb zircon age constraints on the transition from subduction to marginal breakup in the Southwest Pacific. J. Geol. 118, 381–397. Cluzel, D., Adams, C.J., Maurizot, P., Meffre, S., 2011. Detrital zircon records of Late Cretaceous syn-rift sedimentary sequences of New Caledonia: an Australian provenance questioned. Tectonophysics 501, 17–27. Cluzel, D., Maurizot, P., Collot, J., Sevin, B., 2012. An outline of the geology of New Caledonia; from Permian–Mesozoic southeast Gondwanaland active margin to Cenozoic obduction and supergene evolution. Episodes 35, 72–86. Condie, K.C., Belousova, E., Griffin, W.L., Sircombe, K.N., 2009. Granitoid events in space and time: constraints from igneous and detrital zircon age spectra. Gondwana Res. 15, 228–242. Dodson, M.H., Compston, W., Williams, I.S., Wilson, J.F., 1988. A search for ancient detrital zircons in Zimbabwean sediments. J. Geol. Soc. 145, 977–983. Fedo, C.M., Sircombe, K.N., Rainbird, R.H., 2003. Detrital zircon analysis of the sedimentary record. Zircon 53, 277–303. Fergusson, C.L., Henderson, R.A., Offler, R., 2017. Late Neoproterozoic to early Mesozoic sedimentary rocks of the Tasmanides, eastern Australia. In: Sediment Provenance. Elsevier, pp. 325–369. Chapter 13. Flöttmann, T., Gibson, G.M., Kleinschmidt, G., 1993. Structural continuity of the Ross and Delamerian orogens of Antarctica and Australia along the margin of the paleo-Pacific. Geology 21, 319–322. Gaina, C., Müller, D.R., Royer, J-Y., Stock, J., Hardebeck, J., Symonds, P., 1998. The tectonic history of the Tasman Sea: a puzzle with 13 pieces. J. Geophys. Res., Solid Earth 103, 12413–12433. Gaina, C., Muller, R.D., Royer, J.Y., Symonds, P., 1999. Evolution of the Louisiade triple junction. J. Geophys. Res., Solid Earth 104, 12927–12939. Ge, R.F., Wilde, S.A., Nemchin, A.A., Whitehouse, M.J., Bellucci, J.J., Erickson, T.M., Frew, A., Thern, E.R., 2018. A 4463 Ma apparent zircon age from the Jack

103

Hills (Western Australia) resulting from ancient Pb mobilization. Geology 46, 303–306. Gehrels, G., 2014. Detrital zircon U–Pb geochronology applied to tectonics. Annu. Rev. Earth Planet. Sci. 42, 127–149. Ibañez-Mejia, M., Pullen, A., Pepper, M., Urbani, F., Ghoshal, G., Ibañez-Mejia, J.C., 2018. Use and abuse of detrital zircon U–Pb geochronology—a case from the Río Orinoco delta, eastern Venezuela. Geology 46, 1019–1022. Korsch, R.J., Adams, C.J., Black, L.P., Foster, D.A., Fraser, G.L., Murray, C.G., Foudoulis, C., Griffin, W.L., 2009a. Geochronology and provenance of the late Paleozoic accretionary wedge and Gympie Terrane, New England Orogen, eastern Australia. Aust. J. Earth Sci. 56, 655–685. Korsch, R.J., Totterdell, J.M., Cathro, D.L., Nicoll, M.G., 2009b. Early Permian east Australian rift system. Aust. J. Earth Sci. 56, 381–400. Kusiak, M.A., Whitehouse, M.J., Wilde, S.A., Nemchin, A.A., Clark, C., 2013. Mobilization of radiogenic Pb in zircon revealed by ion imaging: implications for early Earth geochronology. Geology 41, 291–294. Ludwig, K.R., 2003. Isoplot 3.75: A Geochronological Toolkit for Microsoft Excel. Special Publication. Berkeley Geochronology Center. p. 75. Matthews, K.J., Williams, S.E., Whittaker, J.M., Müller, R.D., Seton, M., Clarke, G.L., 2015. Geologic and kinematic constraints on Late Cretaceous to mid Eocene plate boundaries in the southwest Pacific. Earth-Sci. Rev. 140, 72–107. Mezger, K., Krogstad, E.J., 1997. Interpretation of discordant U–Pb zircon ages: an evaluation. J. Metamorph. Geol. 15, 127–140. Nemchin, A.A., Cawood, P.A., 2005. Discordance of the U–Pb system in detrital zircons: implication for provenance studies of sedimentary rocks. Sediment. Geol. 182, 143–162. Paton, C., Hellstrom, J., Paul, B., Woodhead, J., Hergt, J., 2011. Iolite: freeware for the visualisation and processing of mass spectrometric data. J. Anal. At. Spectrom. 26, 2508–2518. Pearce, N.J.G., Perkins, W.T., Westgate, J.A., Gorton, M.P., Jackson, S.E., Neal, C.R., Chenery, S.P., 1997. A compilation of new and published major and trace element data for NIST SRM 610 and NIST SRM 612 glass reference materials. Geostand. Newsl. 21, 115–144. Pirard, C., Spandler, C., 2017. The zircon record of high-pressure metasedimentary rocks of New Caledonia: implications for regional tectonics of the southwest Pacific. Gondwana Res. 46, 79–94. Rosenbaum, G., 2018. The Tasmanides: Phanerozoic tectonic evolution of eastern Australia. Annu. Rev. Earth Planet. Sci. 46, 291–325. Saylor, J.E., Knowles, J.N., Horton, B.K., Nie, J., Mora, A., 2013. Mixing of source populations recorded in detrital zircon U–Pb age spectra of modern river sands. J. Geol. 121, 17–33. Schellart, W.P., Lister, G.S., Toy, V.G., 2006. A Late Cretaceous and Cenozoic reconstruction of the Southwest Pacific region: tectonics controlled by subduction and slab rollback processes. Earth-Sci. Rev. 76, 191–233. Seton, M., Müller, R.D., Zahirovic, S., Gaina, C., Torsvik, T., Shephard, G., Talsma, A., Gurnis, M., Turner, M., Maus, S., Chandler, M., 2012. Global continental and ocean basin reconstructions since 200 Ma. Earth-Sci. Rev. 113, 212–270. Shaanan, U., Rosenbaum, G., 2018. Detrital zircons as palaeodrainage indicators: insights into southeastern Gondwana from Permian basins in eastern Australia. Basin Res. 30, 36–47. Shaanan, U., Rosenbaum, G., Wormald, R., 2015. Provenance of the early Permian Nambucca Block (eastern Australia) and implications for the role of trench retreat in accretionary orogens. Geol. Soc. Am. Bull. 127, 1052–1063. Shaanan, U., Rosenbaum, G., Hoy, D., Mortimer, N., 2018. Late Paleozoic geology of the Queensland Plateau (offshore northeastern Australia). Aust. J. Earth Sci. 65, 357–366. Shaanan, U., Rosenbaum, G., Sihombing, F.M.H., in press. Continuation of the Ross– Delamerian Orogen: insights from eastern Australian detrital-zircon data. Aust. J. Earth Sci. https://doi.org/10.1080/08120099.2017.1354916. Sharman, G.R., Johnstone, S.A., 2017. Sediment unmixing using detrital geochronology. Earth Planet. Sci. Lett. 477, 183–194. Sircombe, K.N., 2004. AgeDisplay: an EXCEL workbook to evaluate and display univariate geochronological data using binned frequency histograms and probability density distributions. Comput. Geosci. 30, 21–31. Sircombe, K.N., Hazelton, M.L., 2004. Comparison of detrital zircon age distributions by kernel functional estimation. Sediment. Geol. 171, 91–111. Sláma, J., Košler, J., Condon, D.J., Crowley, J.L., Gerdes, A., Hanchar, J.M., Horstwood, M.S.A., Morris, G.A., Nasdala, L., Norberg, N., Schaltegger, U., Schoene, B., Tubrett, M.N., Whitehouse, M.J., 2008. Plešovice zircon – a new natural reference material for U–Pb and Hf isotopic microanalysis. Chem. Geol. 249, 1–35. Vermeesch, P., 2004. How many grains are needed for a provenance study? Earth Planet. Sci. Lett. 224, 441–451. Vermeesch, P., 2012. On the visualisation of detrital age distributions. Chem. Geol. 312, 190–194. Vermeesch, P., 2018. Dissimilarity measures in detrital geochronology. Earth-Sci. Rev. 178, 310–321.