Albaillellaria from the New England orogen, Eastern NSW, Australia

Albaillellaria from the New England orogen, Eastern NSW, Australia

Marine Micropaleontology, 21 (1993) 353-367 353 Elsevier Science Publishers B.V., Amsterdam Albaillellaria from the New England orogen, Eastern NSW...

3MB Sizes 5 Downloads 64 Views

Marine Micropaleontology, 21 (1993) 353-367

353

Elsevier Science Publishers B.V., Amsterdam

Albaillellaria from the New England orogen, Eastern NSW, Australia Jonathan C. Aitchison Department of Geology and Geophysics, University of Sydney, Edgeworth David Building, F05, Sydney, NSW 2006, Australia (Received January 20, 1992; revision accepted October 20, 1992)

ABSTRACT Aitchison, J.C., 1993. Albaillellaria from the New England orogen, Eastern NSW, Australia. In: D. Lazarus and P. De Wever (Editors), Interrad VI. Mar. Micropaleontol., 2 l: 353-367. Radiolarian data provide important age constraints on the development of terranes within the New England orogen and have implications for existing tectonic models. Most radiolarian assemblages recovered from the orogen are of Late Devonian to Early Carboniferous ages. Albaillellaria comprise a minor proportion of the faunas present but have major biostratigraphic significance. Holoeciscus Foreman, Helenifore Nazarov and Ormiston, Circulaforma Cheng, Ceratoikiscure Deflandre, Protoalbaillella Cheng, and Albaillella Deflandre, two new genera and three new species are found at various stratigraphic levels. Eleven radiolarian assemblages are recognised. In stratigraphic order these are the Helenifore

laticlavium-Ceratoikiscum planistellare, Protoholoeciscus hindea, Holoeciscus formanae, Paraholoeciscus bingaraensis, Ceratoikiscum umbraculum, Protoalbaillella anaiwanensis, Albaillella paradoxa, Albaillella undulata-Albaillella indensis, AIbaillella indensis-AIbaillella furcata, Albaillella cartalla-Albaillella thomasi and Circulaforma omicron assemblages. There is an apparent biostratigraphic succession amongst the Albaillellaria in the New England orogen in which Protoholoeciscus hindea n. gen. n. sp. is transitional between Ceratoikiscum Deflandre and Holoeciscus Foreman and Paraholoeciscus bingaraensis n. gen. n. sp. is transitional between Holoeciscus Foreman and the Albaillella paradoxa Deflandre group.

Introduction The New England orogen (NEO) of eastern Australia is a tectonic collage comprising various terranes which amalgamated, accreted or otherwise interacted during late Paleozoicearly Mesozoic time (Flood and Aitchison, 1988; Coney et al., 1990). Differences in the tectonic settings and relative motions of the constituent terranes, together with their subsequent post-accretionary interactions, disruption, and dispersal, has produced the complex geology now observed (Fig. 1 ). In order to understand the evolution of the NEO, age constraints must be placed on the development of constituent terranes. Macrofossils are not common in some of the terranes. However, radiolarians which occur in many of the 0377-8398/93/$06.00

sedimentary lithofacies of the orogen, are providing a means of accurately dating strata (Ishiga et al., 1987, 1988; Blake and Murchey, 1988; Aitchison, 1988a,b,c, 1989, 1990; Aitchison and Hood, 1990; Aitchison et al., 1992 ). Radiolarian age data profoundly affect interpretation of NEO geology and illustrate how important radiolarians can be in the study of complex tectonic collages. Three major terranes have been sampled for radiolarians, and minor preliminary work in some of the other terranes has commenced recently. The Gamilaroi terrane, the westernmost of the New England terranes, is a Devonian intra-oceanic island arc which developed in isolation from the continental margin of Gondwana (Aitchison and Flood, in prep). Toward the end of the Devonian, this arc was

© 1993 Elsevier Science Publishers B.V. All rights reserved.

354

J.C. AITCHISON i

151 °

152°

LEGEND Birpai terrane Yugambal terrane Djungati terrane Anaiwan terrane Gamilaroi terrane •

radiolarian locality

li!! 31°.

.31°~

. . . . . . . .

(7-



0 !

km 50 I

Fig. 1. Tectonostratigraphic terrane map of the New England orogen of eastern Australia. Distribution of major terranes discussed in this paper is shown along with the locations of towns mentioned in the text. Major localities from which various radiolarian assemblages have been collected are also indicated.

ALBAILLELLARIAFROM THE NEW ENGLAND OROGEN, EASTERNNSW

accreted to the continental margin of Gondwana. Radiolarians occur in siliceous tufts of this terrane, which includes the classic locality described by Hinde in 1899. The Djungati terrane, immediately to the east of the Gamilaroi terrane comprises a disrupted basalt, chert, volcaniclastic siltstone, sandstone, and conglomerate succession. Rare limestone olistoliths occur in several of the conglomerate horizons. Radiolarian chert is the dominant lithology in the Djungati terranc and results of detailed radiolarian studies have led to the elucidation of the original stratigraphy of this terrane prior to tectonic disruption (Aitchison et al., 1992). The Anaiwan terrane is an extensive lithotectonic entity that lies east of the Djungati terrane. It contains minor basalt, ribbon-bedded tuffaceous chert, tuffaceous siltstones and volcaniclastic sandstones. A ghosted stratigraphic succession has been resolved using radiolarian biostratigraphy (Aitchison et al., 1992). Volcaniclastic arc-derived sandstones are the dominant lithology in the Anaiwan terrane (Korsch, 1984) which is interpreted as a subduction complex (Fergnsson and Flood, 1984). Radiolarian assemblages have been found at numerous localities, and some wellpreserved assemblages have been documented (Aitchison, 1990; Aitchison and Flood, 1990), Radiolarians found, to date, in the Anaiwan terrane range from latest Devonian (Famennian) to Early Carboniferous (Visean).

New England radiolarian biostratigraphy Radiolarians are abundant in siliceous sedimentary rocks of the NEO. However, preservation conditions are such that itis rare to find more than a single radiolarian assemblage in any ~)utcrop despite the occurrence of chert sequences at least I00 m thick. Unlike many cherts from the northern hemisphere, conodonts are extremely rare.Commonly only a few layersyield identifiableradiolarians,and as yet, no biostratigraphic successions have been re-

355

covered from any single outcrop. M a n y samples contain only a single age-diagnostic species together with many somewhat less useful species. Nevertheless, because the volume of information concerning the biostratigraphy of Devonian to Early Carboniferous radiolarians has dramatically increased in the past decade (Foreman, 1963; Nazarov, 1975, 1988; Holdsworth and Jones, 1980; Won, 1983; Sandberg and Gutschick, 1984; Nazarov and Ormiston, 1985, 1986, in press; Cheng, 1986; GourmcIon, 1987; Holdsworth and Murchey, 1988; Braun, 1989a,b,c, 1990a,b; Schwartzapfel, 1990; Aitchison, in press) accurate age estimates of even poorly preserved faunas can now be made. Rapid diversificationof radiolarians during the latestDevonian and Early Carboniferous isevident in well-preserved faunas from the Canning Basin (Frasnian) of western Australia,the Oauchita Mountains (FamennianTournaisian) in the USA, and stratain Europe (Tournaisian-Visean). The frst and/or last appearance of morphotypes or morphotype groups can be used to constrain the ages of assemblages. AlbaiileUaria are the most biostratigraphically useful of the radiolarians present in the NEO. Although they are rare their utility results from their rapid evolution and their distinctive forms (Plate I). They are commonly readily identifiable in even least well preserved of faunas present in the NEO. In contrast, the more abundant spherical radiolarians tend to be infflled with secondary silica that obscures original internal structures and precludes identification below the order level. Direct confirmation of radiolarian age estimates for NEO faunas using co-occurring microfossil taxa is generally impossible. Less than l0 conodont elements have been recovered from 2500 chert samples. However, as the characteristics of N E O radiolarian faunas are similar to those described from the northern hemisphere, accurate age estimates are possible. N E O radiolarian faunas arc predominantly of Late Devonian to Early Carboniferous ages and they

356

J.C. AITCHISON

ALBAILLELLARIAFROMTHENEWENGLANDOROGEN,EASTERNNSW

provide an opportunity to study biostratigraphic trends amongst the Albaillellaria. Several distinct radiolarian assemblages based on the Albaillellaria are recognised. Each of these assemblages has been recovered from several samples and generally from more than one locality. Localities referred to in this paper are assigned University of New England locality numbers (e.g. L1899). Grid references (GR) which are given relate to Central Mapping Authority ofNSW 1:25,000 and 1:100,000 map sheets. Type and other important specimens are assigned Australian Museum (Sydney) catalogue numbers. Several of the assemblages described herein are well illustrated in previous papers and where appropriate the reader is referred to these works which are cited in the text.

Radiolarian assemblages Helenifore laticlavium-Ceratoikiscum planistellare assemblage This assemblage is the oldest readily identifiable radiolarian assemblage known from the New England orogen. The Yarrimie Forma-

357

tion (Crook, 1961 ), the uppermost unit of the Tamworth Group (part of the Gamilaroi terrane), contains abundant radiolarians. Radiolarians are conspicuous in hand specimens of tuffaceous siltstone. However, they are not always well-preserved because they are commonly replaced by low-grade burial metamorphic minerals. Nevertheless, in a classic work, Hinde (1899) described 53 species of radiolarians from thin-sections of dark-coloured (black) siliceous limestones of the Yarrimie Formation collected from exposures at Tamworth Common. This exposure no longer exists, but the Hinde fauna has now been recollected from several localities along strike from the original locality (Aitchison, 1988c, 1989, 1990). Radiolarians present include: Entactinosphaera grandis Nazarov, Entactinosphaera vetusta (Hinde), Entactinia spp., Entactinia additiva? Foreman, Ceratoikiscum sp. cf. C. avimexpectans Deflandre group, Spongentactinella corynacantha Nazarov and Ormiston, Spongentactinella cf. Spongentactinella sp. 2 of Nazarov and Ormiston, Staurodruppa praelonga (Hinde) and Palaeoscenidium cladophorum Deflandre variants. Large entactinids with robust three-bladed spines dominate the assemblage, but their biostratigraphic utility is

PLATE I Characteristic Albaillellaria from the New England orogen of eastern Australia. Length of scale bar in microns is indicated in parentheses. Australian Museum (AMF) number and locality map sheet and grid reference are given for each specimen figured. 1. Helenifore laticlavium ( 130/zm) AMF.74687, Pigna Barney 9234-3-N GR724856. 2. Ceratoikiscum planistellare ( 130/~m), AMF.74687, Glenrock 9134-I-S, 527951. 3. Protoholoeciscus hindea n. sp. ( 130/~m), AMF. 74688, Barry 9134-1-N GR 391037. 4. Holoeciscusformanae Cheng (80/~m) AMF74509, Bingara 9038-I-N GR777960. 5. Paraholoeciscus bingaraensis n. sp. ( 110/zm) AMF.74503, Bingara 9038-111-N GR 647041. 6. Ceratoikiscum umbraculum Won, AMF.74545, Jackadgery 9438-4-N GR 542303. 7. Protoalbaillella anaiwanensis n. sp. (65/zm) AMF.74550, Jackadgery 9438-4-N GR 542303. 8. Albaillella paradoxa Deflandre Group (90/lm ) AMF. 74473, Armidale 9236 GR733170. 9. Albaillella undulata Deflandre ( 155/~m) AMF. 74646, Bundarra 9137 GR248341. 10. Albaillella indensis Won ( 105/zm) AMF.74658, Bundarra 9137 GR 199413. l 1. Albaillellafurcata Won ( 130 #m) AMF. 74663, Bundarra 9137 GR 199413. 12. Albaillella cartalla Ormiston and Lane ( 165/zm), AMF. 74684, Texas 9140 GR345154. 13. Albaillella thomasi Braun ( 130/zm) AMF.74685, Texas 9140 GR345154. 14. Circulaforma omicron Ormiston and Lane ( 130/zm) AMF.74686, Glenrock 9134-I-S GR499947.

358 low because their internal detail is commonly poorly preserved and their range is not well constrained. Recent sampling has resulted in the discovery of a very well-preserved typical Yarrimie Formation radiolarian fauna at Glenrock station south of Tamworth. At this locality rare, delicate specimens of Helenifore laticlavium Nazarov and Ormiston occur with Ceratoikiscum planistellare Foreman and the other radiolarians mentioned above. On the basis of current radiolarian biostratigraphic knowledge the co-occurrence of these two species appears to indicate that this assemblage, and thus that part of the Yarrimie Formation is of Late Devonian (probably late Frasnian) age. This is significant because abundant conodont faunas in limestone lenses in the Yarrimie Formation have been used to establish a Middle Devonian age for the Yarrimie Formation (Philip and Pedder, 1966). Although this conodont age has been widely inferred to represent the depositional age of the formation, it has never been clearly established whether these limestones are autochthonous or allochthonous, and some workers (McMinn, 1982) have considered that the Yarrimie Formation may locally be as young as Frasnian. The Hinde radiolarian fauna confirms the allochthonous nature of at least some of the limestones in the Yarrimie Formation. Reassessment of local stratigraphy should be undertaken prior to development of new models for the tectonic evolution of the Gamilaroi terrane. However, further work on Middle Devonian radiolarians is required to establish the maximum ages/first occurrences of both Helenifore laticlavium Nazarov and Ormiston and Ceratoikiscum planistellare Foreman. Poorly-preserved radiolarian faunas from red ribbon-bedded chert of the Woolomin Group, part of the Djungati terrane have been recovered from between Pigna Barney and Gloucester (Aitchison et al., 1992). They contain Helenifore sp. together with distinctive entactinids with robust three-bladed spines and are considered to be poorly preserved rein-

J.c. AITCHISON nants of the Helenifore laticlavium-Ceratoikiscum planistellare assemblage. Helenifore sp. is commonly quite robust and readily identifiable even in poorly preserved faunas. Numerous specimens referable to Helenifore laticlavium have recently been recovered, together with entactinids with robust three bladed spines, from samples of siliceous tufts in the Willowie Creek beds of the Yugambal terrane near Jackadgery (Camelback 9439-3-S GR689417) and siliceous tufts of the Birpai terrane near Yarras (Birdwood 9335-II-N GR 333313 F.C.P. Spiller, Univ. New England, unpubl, data) indicating a similar age for some of the rocks in these two terranes.

Protoholoeciscus hindea assemblage A new radiolarian taxon, Protoholoeciscus hindea n. gen. n. sp. is common in a fauna represented in several samples from red ribbonbedded and locally massive manganiferous cherts of the Woolomin Group (Djungati terrane) which form large roadside bluffs along the Barnard River northwest of Barry Station. These cherts have yielded moderately wellpreserved radiolarian faunas dominated by entactiniids with robust three-bladed spines. The new radiolarian genus Protoholoeciscus is somewhat similar to Glanta described by Wakamatsu et al. (1990) from Upper Devonian rocks in the Kurosegawa terrane of southwestern Japan and to Huasha described from the Famennian of Oklahoma and Arkansas, USA, by Cheng (1986). Rare poorly-preserved specimens assignable to Helenifore are also present together with entactiniids with robust threebladed spines. A preliminary interpretation of the age of this fauna is Late Devonian (probably latest Frasnian to earliest Famennian) because the new genus Protoholoeciscus n. gen., appears to represent a transitional form on an evolutionary pathway between Ceratoikiscum and Holoeciscus.

359

ALBAILLELLARIA FROM THE NEW ENGLAND OROGEN, EASTERN NSW

Holoeciscusformanae assemblage Radiolarians are common in fine-grained lithologles such as chert, siliceous siltstones, and tuffaceous sedimentary rocks throughout the Anaiwan terrane. The oldest well-preserved assemblage has been recovered from east of Bingara in the northwest of the terrane (Aitchison, 1990) and in the southwest of the terrane at Yarrowitch (Aitchison et al., 1992 ). The fauna contains abundant specimens of Holoeciscusformanae Cheng. This species appears to be quite robust, surviving in a recognisable form even when most other radiolarians are unidentifiable. The best preserved fauna containing this assemblage, from near Bingara, includes: Holoeciscus formanae Cheng, Ceratoikiscum sp., Archocyrtium spp., Cyrtentactinia spp., Palaeoscenidium cladophorum Deflandre variants and numerous spheroidal radiolarians with three-bladed spines (Aitchison, 1990). The co-occurrence of Holoeciscus formanae Cheng, Pylentonema and/or Cyrtisphaeractenium together with the absence of spheroidal radiolarians with twisted three-bladed spines in this assemblage indicates probable affinity with the middle Famennian Holoeciscus 2 assemblage of Holdsworth and Jones (1980). Holoeciscus formanae has also recently been recovered siliceous tufts of the Birpai terrane near Yarras (Yarras 9335-II-S 353233 F.C.P. Spiller, Univ. New England, unpubl, data) and from detrital chert clasts in Lower Permian sedimentary rocks of the Manning Group (Vickers and Aitchison, 1992).

Paraholoeciscus bingaraensis assemblage Radiolarians, although they are generally not well-preserved in the Djungati terrane, are found in some outcrops east of Bingara, at Burnima (Aitchison, 1990). Radiolarians in these strata include an assemblage containing: Paraholoeciscus bingaraensis n . sp., Palaeoscenidium cladophorum Deflandre variants,

Entactinosphaera spp. and Entactinia spp. including forms with sinistrally twisted threebladed spines. Paraholoeciscus bingaraensis possesses a spinose rather than spongy H-frame like that ofHoloeciscus auceps Foreman. It appears to represent a form transitional between Holoeciscus formanae Cheng and the Albaillella paradoxa Deflandre group and is similar to an undescribed form from Poland (M. Paskowski, Cracow, Poland unpubl, data; see Discussion). It is thought to be of latest Devonian age, and the co-occurrence of entactiniids with twisted three-bladed spines supports this age assignment.

Ceratoikiscum umbraculum assemblage Well-preserved radiolarian faunas are common in thin-bedded red tuffaceous siltstones of the Cara Formation in the west of the Anaiwan terrane near Bingara. Samples from several localities (Aitchison, 1990) contain an assemblage which includes the following taxa: Ceratoikiscum umbraculum Won, Ceratoikiscum avimexpectans Deflandre group, Palaeoscenidium cladophorum Deflandre variants, Cyrtisphaeractenium spp., Archocyrtium coronaesimile Won, Archocyrtium spp., Cerarchocyrtium spp., Mostlerium sp., Entactinosphaera spp. and Staurodruppa sp. aft. S. prolata Foreman. The presence of abundant archocyrtids such as Cyrtisphaeractenium spp., Cerarchocyrtium spp. and Mostlerium sp., in association with Ceratoikiscum umbraculum Won, and Ceratoikiscum avimexpectans Deflandre group, indicates Early Carboniferous (Tournaisian) affinities. Holoeciscus and Albaillella are noticeably absent from faunas containing this assemblage. The absence of Albaillella species from this earliest Carboniferous assemblage may indicate that it predates evolution or arrival of this form in eastern Australia or it may represent some form of paleoecological control on the abundance of various radiolarian species.

360

Protoalbaillella anaiwanensis assemblage

J.C.AITCHISON flandre group and Staurodruppa prolata Foreman. This assemblage is interpreted to be younger than Protoalbaillella anaiwanensis assemblage because, although Albaillella paradoxa Deflandre group is present, Protoalbaillella anaiwanensis n. sp. (which is considered to be a slightly older radiolarian; Cheng, 1986) is absent. Rare specimens of Kantollum undulatum Cheng are also present and the faunas containing this assemblage are generally dominated by archocyrtids.

In the eastern part of the Anaiwan terrane near Jackadgery light-brown ribbon-bedded cherts have yielded a well-preserved, diverse radiolarian fauna (Aitchison, 1990). Several important taxa here are: Protoalbaillella anaiwanensis n. sp., Albaillella paradoxa Deflandre group, Ceratoikiscum avimexpectans Deflandre group, Palaeoscenidium cladophorum Deflandre variants, Pylentonema spp., Quadrapesus sp., Archocyrtium riedeli Deflandre, Archocyrtium sp. of. A. castuligerum Deflandre, Archocyrtium spp., Cyrtisphaeractenium spp., Deflandrellium sp., Mostlerium sp., Polyentactinia spp. and numerous entactiniids. Although entactiniids are abundant, few can be identified at the genus level because nearly all are in filled with silica which prevents the examination of their internal structures. Forms with robust, three-bladed spines are common, and both sinistrally and dextrally twisted three-bladed spines have been observed. The co-occurrence of Protoalbaillella anaiwanensis n. sp. and Albaillella paradoxa Deflandre group indicates that this fauna can be assigned to the Ab2A assemblage zone of Cheng (1986), to which a Tournaisian (Tn2) age is assigned.

Blake and Murchey ( 1988 ) reported the occurrence of a radiolarian fauna in cherts of the Sandon beds in the Anaiwan terrane west of Armidale which includes ?latest Devonianearliest Carboniferous forms such as Staurodruppa? prolata Foreman and Entactinosphaera palimbola Foreman. Further samples collected from this locality (Aitchison and Flood, 1990) also include Albaillella indensis Won, Albaillella undulata Deflandre and Archocyrtium sp. This assemblage occurs together with the conodont Siphonodella crenulata and is interpreted as being of Early Carboniferous (Tournaisian) age.

Albaillella paradoxa assemblage

Albaillella

Albaillella

undulata-Albaillella

indensis

assemblage

indensis-Albaillella

furcata

assemblage An assemblage which is common in samples from the Anaiwan terrane collected around Armidale (Aitchison, 1990) is based on the Albaillella paradoxa Deflandre group. Radiolarians in the assemblage include: Archocyrtium spp., Archocyrtium sp. cf. A. castuligerum Deflandre, Archocyrtium delicatum Cheng, Archocyrtium ludicrum Deflandre, Archocyrtium riedeli Deflandre, Archocyrtium validum Cheng, Archocyrtium venustum Cheng, Archocyrtium wonae Cheng, Cerarchocyrtium sp., Cyrtisphaeractenium spp., Cyrtisphaeractenium spinosum Cheng, Kantollum undulatum Cheng, Palaeoscenidium cladophorum De-

Tuffaceous mudstones in the Sandon beds (Anaiwan terrane) which depositionally overlie the cherts containing the Albaillella undulata-Albaillella indensis assemblage also contain a radiolarian fauna that includes entactiniids, archocyrtids and albaillellids. Radiolarians present in this fauna are moderately well-preserved and include Albaillella indensis Won, Albaillella furcata Won and Archocyrtium spp. (Aitchison and Flood, 1990). Extensive sampling of tuffaceous siltstones along the Gwydir River, south of Bundarra, indicate that occurrences of this assemblage are wide-

361

ALBAILLELLARIA FROM THE NEW ENGLAND OROGEN, EASTERN NSW

spread. The presence of Albaillella indensis Won with both Albaillella furcata Won and rare, small archocyrtids indicates a latest Tournaisian to earliest Visean age (Holdsworth and Murchey, 1988; Braun, 1990b) for this assemblage.

Lane) assemblage have been traced for over 4 km in a zone of Djungati terrane-like rocks. However, these rocks lie west of the main expanse of the Djungati terrane and correlation is tentative.

Albaillella

Some important new Albaillellaria have been discovered in the New England orogen and the are described in this section.

cartalla-Albaillella

thomasi

assemblage Radiolarians found in red ribbon-bedded cherts of the the Texas beds in South Queensland (Aitchison and Flood, 1990) contain poorly preserved entactiniid faunas with numerous specimens of the stauraxon radiolarian Scharfenbergia impella (Ormiston and Lane). The first occurrence of this species is in the early Visean (Holdsworth and Murchey, 1988) and it provides a useful maximum age constraint. Samples from some areas (Aitchison and Flood, 1990) also include Albaillella indensis, Albaillella furcata Won, Albaillella cartalla Ormiston and Lane and Albaillella thomasi Braun. The co-occurrence of these radiolarians indicates that the assemblage is probably of early Visean age (Braun, 1990b).

Circulaforma omicron assemblage Red radiolarian cherts from the Glenrock area which are assigned to the Djungati terrane contain an assemblage which includes abundant specimens of Circulaforma omicron (Ormiston and Lane). The only other identifiable radiolarian in this assemblage is Palaeoscenidium sp. The genus Circulaforma has previously been reported from the USA where its earliest occurrence is in well-dated mid-Carboniferous (Visean) strata (Cheng, 1986). Braun (1990b) also reports the first occurrence ofCirculaforma omicron (Ormiston and Lane) together with stauraxon radiolarians from a similar stratigraphic level in Germany and assigned it to the upper part of his Visean Albaillella cartalla Zone. Cherts which contain the Circulaforma omicron (Ormiston and

Systematic paleontology

Suborder ALBAILLELLARIA Deflandre 1953 emend. Holdsworth 1969 Family Albaillellidae Deflandre 1952 emend. Holdsworth 1977

Protoalbaillella Cheng 1986 Type species: Protoalbaillella deflandrei Cheng 1986.

Protoalbaillella anaiwanensis n. sp. (Plate I, 7) Type material: Holotype AMF.74550, Paratype AMF.74593 (Plate 6.11A and D in Aitchison, 1989) Early Carboniferous (Tournaisian Tn2), Gundahl Complex, Anaiwan terrane, UNE L1899 (Jackadgery 9438-4-N GR 542303), NSW, Australia. Abundant in samples from this locality. Diagnosis: Large imperforate, conical, noncrenulated, lamellar shell. Skeletal framework with central D-shaped closed frame. Apical spine short and delicate in appearance. Apertural margin bounded by a series of apetural spines which are diagonally oriented and point towards the postedo-ventral side of the test. Short rudimentary wing (a.a.) projecting outwards adjacent to the apertural margin. Posterior wing (a.p.) more strongly developed but is short and inclined ventrally at 45 ° . The i.v. extension points directly downwards in a ventral direction. Comparison: This morphotype was contrasted with Protoalbaillella media Cheng by Aitchison (1988b). The characteristics of Protoalbaillella media Cheng are somewhat differ-

362 ent to those of Protoalbaillella anaiwanensis n. sp. Protoalbaillella media Cheng has a more elongate shell. Wings of Protoalbaillella media Cheng are more robust and the shorter rudimentary wing is in a higher position above the apertural margin. The i.v. extension in P. anaiwanensis points diagonally downwards in a posterio-ventral direction, and the apical spine of Protoalbaillella media Cheng is moderately long and sturdy in appearance. Measurements: Taken from 10 specimens. Mean (and range ) given in micrometres. Terminology follows that of Cheng ( 1986 ): h.s. 70 (62-74), w.s. 50 (42-54), h.h. 57 (48-63), w.h. 41 (36-44),i.d'. 19 (14-32),i.v'. 40 (3542), d.w. 38 (32-45), v.w. 39 (34-45). Type localit~ Abundant in samples of brown ribbon-bedded chert from UNE L1899 (Jackadgery), Gundahl Complex, Anaiwan terrane, NSW, Australia. Etymology: Protoalbaillella anaiwani is named for the Anaiwan terrane from which it was first found. Range and occurrence:. Early Carboniferous (Tournaisian Tn2 ), Gundahl Complex, Analwan terrane, NSW, Australia so far as is known. Family Ceratoikiscidae Holdsworth 1969 Protoholoeciscus n. gen. Type species: Protoholoeciscus hindea n. sp. Diagnosis: Test as with family. Triangular frame with a.t. the shortest rod. B.t. and i.t. subequal in length. Lamellar shell rectangular to trapezoidal in lateral view, covering a.t. and dorsal parts of both i.t. and b.t. rods. Large, oblate basal aperture pointing towards i-t- rod. Spines around apetural margin. Five thornshaped rod extensions ( b. v., b.d., i. v., i.d. and a.p. ). A.p ventrally offset along i.t. Comparison: Protoholoeciscus can be distinguished from Ceratoikiscum because of the presence of a lamellar shell. It can be distinguished from Holoeciscus due to the presence of an equilateral triangular frame rather than

J.C.AITCHISON the elongate triangle of Holoeciscus, which has two rods much longer than the third. Range and occurrence: Probably of Late Devonian (latest Frasnian) age. Djungati terrane, NSW, Australia so far as is known. Protoholoeciscus hindea n. sp. (Plate I, 3 ) Type material'. Holotype: AMF.74599 (Paratypes; fig. 6 0 - R in Aitchison et al., 1992) from red chert of the Woolomin Group, Djungati terrane, in the Upper Barnard Valley, (Barry 9134-1-N GR 391037) NSW, Australia. Abundant in samples from this locality. Diagnosis: Test as with genus. Triangular frame with a.t. the shortest rod and b.t. and i.t. subequal in length. B.t. is the longest rod and is strongly curved. Lamellar shell imperforate, sub-rectangular to trapezoidal in lateral view, encasing a.t. and dorsal two thirds of both i.t. and b.t. rods. Large, oblate basal aperture pointing toward i-t- rod. Rare spines around apetural margin. Five thorn-shaped rod extensions ( b. v., b.d., i. v., i.d. and a.p. ). Robust patagium developed along ventral portion of b. t., i.t. and b.v. Measurements: Taken from 20 specimens. Mean (and range) given in micrometres. Terminology follows that shown on Fig. 3 (h.s. and w.s. refer to the height and width of the shell, respectively): h.s. 120 (103-139), w.s. 80 (7189), a.t. 20 (10-25),b.d. 18 ( l l - 2 1 ) , b . t . 145 (134-156), b.v. 25 (18-34), i.v. 27 (10-40), i.t. 95 (83-104), i.d. (beyond a.p.) 64 (5271 ), a.p. 42 (38-50). Type locality: Abundant specimens from red cherts of the Woolomin Group, Djungati terrane, in the Upper Barnard Valley, NSW, Australia. Etymology: Named to honour G.J. Hinde for his pioneering work on New England radiolarians. Range and occurrence: Probably of Late Devonian (Famennian) age. Woolomin Group, Djungati terrane, NSW, Australia so far as is known.

363

ALBAILLELLARIA FROM THE NEW ENGLAND OROGEN, EASTERN NSW

Family Holoeciscidae Cheng 1986 Paraholoeciscus n. gen. Type species: Paraholoeciscus bingaraensis n. sp. Diagnosis: Triangular frame with a.t. the shortest rod and b.t. and i.t. subequal in length. A.t. curves towards b.t. Lamellar shell rectangular to trapezoidal in lateral view, covering a.t. and dorsal two thirds of both i.t. and b.t. rods with a large, circular basal aperture pointing towards b-i- junction point. Several pairs of caveal ribs, obliquely arranged, indistinct but traceable along the surface of the lamellar shell. Lamellar shell rarely with small pores developed on it. Marginal spines around apetural margin. V-shaped intersection between b.t. and i.t. rods which diverge at approximately 50 ° beyond the b-i-junction. Comparison: May be a form transitional between Holoeciscusformanae Nazarov and Ormiston and Albaillella paradoxa Deflandre. Can be distinguished from Holoeciscus in which the a rod lies at approximately 90 * to the i and b rods. a.p. remains but only as a small node marking the intersection of a and i rods. The characteristic H-frame of Albaillella, first seen in A. paradoxa is not yet developed. Range and occurrence: Probably of Late Devonian (Famennian) or possibly earliest Carboniferous age. Upper Bobs Creek Formation, Djungati terrane, NSW, Australia so far as is known. Paraholoeciscus bingaraensis n. sp. (Plate I, 5 ) Type material: Holotype: AMF.74503, from UNE L1904 (Bingara 9038-111-N GR 647041 ), Djungati terrane, NSW, Australia. Numerous other fragmentary specimens also obtained from this locality. Diagnosis: Triangular frame with a.t. the shortest rod and b.t. and i.t. subequal in length. Lamellar shell rectangular to trapezoidal in lateral view, covering a.t. and dorsal two thirds

of both i.t. and b.t. rods with a large, circular basal aperture pointing towards b-i- junction point. Five to six pairs of caveal fibs, obliquely arranged, indistinct but traceable along the surface of the lamellar shell. Marginal spines around apetural margin. V-shaped intersection between b.t. and i.t. rods which diverge at approximately 50 ° beyond the b-i- junction. Small node developed as a.p. rod at intersection ofa.t, and i.t. rods. Material: Several specimens from green tuffaceous cherts of the upper Bobs Creek Formation at UNE L1904 (Burnima) in the Anaiwan terrane, NSW, Australia. Measurements: Taken from 5 specimens. Mean (and range) given in micrometres. Terminology follows that shown on Fig. 3 (h.s. and w.s. refer to the height and width of the shell, respectively): h.s. 150 (133-164), w.s. 80 (7285), a.t. 74 (69-79), b.d. 5 (3-7), b.t. 190 (171-204), b.v. 23 (19-34), i.v. 47 (36-55), i.t. 152 (136-159),a.p. 3 (2-5). Etymology: Named for the Bingara township near which it was discovered. Range and occurrence:. Probably of Late Devonian (Famennian) or possibly earliest Carboniferous age. Upper Bobs Creek Formation, Djungati terrane, NSW, Australia so far as is known. Discussion

The Albaillellaria are an extremely significant if minor portion of the faunas in Late Devonian to Early Carboniferous sedimentary rocks of the New England orogen. Eleven radiolarian assemblages can be recognised in the component terranes. Although preservation conditions are such that commonly only a few samples from any outcrop will produce recognisable radiolarians, the stratigraphic order of the NEO radiolarian assemblages can be determined (Fig. 2). This is done by comparison with Northern Hemisphere radiolarian biostratigraphy and by examining assemblages from areas where the stratigraphic order of

364

J.C. AITCHISON

Devonian Frasnian

Carboniferous

' Famennian

Tournaisian

,

Visean

,, ?

' ?

Helenifore laticlavium - Ceratoikiscum planistellare

'

?Protoholoecfscus hindea ' Holoeciscus formanae , J Paraholoeciscus bingaraensis , i Ceratoikiscum umbraculum n Protoalbaillella anaiwanensis , Albaillella paradoxa Albail/ella undulata - Albaillella indensis ~ ' Albaillella indensis - Alffaillella furcata ' Albaillefla cartalla - Albaillella thomasi Circulaforma omicron i

,

i

i

Fig. 2. Possible zonation of Late Devonian to Early Carboniferous radiolarian assemblages in the New England orogen of eastern Australia.

b.d.

hd

i.d.

a.a,

a.p.

a.p.

i.t.

).v. ~ Holoeciscus

b.d.~ a.a.

|

-:."

~

Lv.

b.v.

Paraholoeciscus

Albaillella

/i.d. a.t.

/;.- a.p.

;';itt.

,.v.

i.v. A

b'v"

Protoholoeciscus

Ceratoiksicum

Fig. 3. Possible evolutionary trend from Ceratoikiscum through Protoholoeciscus to Holoeciscus then Paraholoeciscus to Albaillella inferred from radiolarian assemblages of the New England orogen, eastern Australia.

ALBAILLELLARIAFROMTHE NEW ENGLANDOROGEN,EASTERNNSW

arealy separated outcrops is determinable (Aitchison et al., 1992). Although now widely separated, it is likely that many northern hemisphere radiolarian rocks of Late Devonian to Early Carboniferous age formed at similar latitudes to those now present in eastern Australia (Aitchison, 1990) and this provides a legitimate basis for detailed comparison. In stratigraphic order the assemblages are: (1) Helenifore laticlavium-Ceratoikiscum planistellare assemblage, (2) Protoholoeciscus hindea assemblage, (3) Holoeciscusformanae assemblage, (4) Paraholoeciscus bingaraensis assemblage, (5) Ceratoikiscum umbraculum assemblage, (6) Protoalbaillella anaiwanensis assemblage, (7) Albaillella paradoxa assemblage, (8) Albaillella undulata-Albaillella indensis assemblage, (9) Albaillella indensis-Albaillella furcata assemblage, (10) Albaillella cartalla-Albaillella thomasi assemblage and ( 11 ) Orculaforma omicron assemblage. Two significant new genera have been discovered in the NEO and these radiolarians may elucidate aspects of Albaillellacid evolution. It is suggested that the two new genera lie along a transitional evolutionary pathway between well known AlbailleUacid genera. The suggested transition differs from those postulated by Holdsworth (1969), Won ( 1983 ) and Cheng (1986). However, it is presented here as an alternative interpretation and it can be seen clearly between Plate I, 2, 3 and 4. The evolutionary pathway is schematically illustrated in Fig. 3. Protoholoeciscus n. gen. is a form that appears in the late Frasnian and seems to be transitional from Ceratoikiscum Deflandre to Holoeciscus Foreman. In this new genus the major feature is the fusion of the caveal ribs of Ceratoikiscum Deflandre to form a lamellar shell similar to that of Holoeciscus Foreman. There is a corresponding change in the relative lengths of the a, b and i rods and reduction in the patagium. A and b rods are longer and more parallel. The a.p. rod is displaced ventrally along i.t. Paraholoeciscus n. gen. appears in Famennian faunas and may be a form that is

365

transitional between Holoeciscus Deflandre and the Albaillella paradoxa Deflandre group. The a.t. and i.t. rods appear to merge with a vestigial node (a.p.) remaining at their intersection. Further straightening of the a.t. and i.t. rods and development of a short rod at the intersection of the i and b. rods may have completed the evolutionary transition to Albaillella paradoxa which first appeared around the Devonian/Carboniferous boundary. The discovery of these two new AlbaiUellacid genera may help to further elucidate phylogentic relationships between Late Devonian to Early Carboniferous radiolarians.

Acknowledgements I gratefully acknowledge the financial assistance of the Australian Research Council (grant to P.G. Flood, UNE). Assistance with Scanning Electron Microscopy was provided by the Electron Microscope Units of University of New England and University of Sydney. Peter Flood is thanked for encouragement and numerous discussions on New England geology. I also thank Frances Spiller for her unceasing enthusiasm in processing the most unlikely of samples. This work is a contribution to IGCP 267.

References Aitchison, J.C., 1988a. Early Carboniferous (Tournaisian) Radiolaria from the Neranleigh-Fernvale beds, Lake Manchester, Queensland, Australia. Queensl. Gov. Min. J., 89: 240-241. Aitchison, J.C., 1988b. Late Paleozoic radiolarian ages from the Gwydir terrane, New England orogen, eastern Australia. Geology, 16: 793-795. Aitchison, J.C., 1988c. Radiolaria from the southern part of the New England Orogen, eastern Australia. In: J.D. Kleeman (Editor), New England Orogen: Tectonics and Metallogenesis. Univ. New England, Armidale, Australia, pp. 49-60. Aitchison, J.C., 1989. Paleozoic radiolarians and lithotectonic terranes of the southern New England Orogen, eastern Australia. Ph.D. Thesis, Univ. New England, Armidale, Australia. Aitchison, J.C., 1990. Significance of Devonian-Carbon-

366 iferous radiolarians from accretionary terranes of the New England Orogen, eastern Australia. Mar. Micropateontol., 15: 365-378. Aitchison, J.C., in press. Late Devonian (Frasnian) Radiolaria of the Canning Basin, Western Australia. Palaeont. Abt. A. Aitchison, J.C. and Flood, P.G., 1990. Early Carboniferous radiolarian ages constrain the timing of sedimentation within the Anaiwan terrane, New England orogen, eastern Australia. Neues Jahrb. Geol. Pal~iontol. Abh., 180: 1-19. Aitchison, J.C., Hood, P.G. and Spiller, F.C.P., 1992. Tectonic setting and paleoenvironment of terranes in the southern New England orogen as constrained by radiolarian biostratigraphy. Palaeogeogr., Palaeoclimatol., Palaeoecol., 94:31-54. Blake, M.C., Jr. and Murchey, B., 1988. A California model for the New England fold belt. In: J.D. Kleeman (Editor), New England Orogen: Tectonics and Metallogenesis. Univ. New England, Armidale, Australia, pp. 20-31. Braun, A., 1989a. Neue unterkarhonische RadiolarienTaxa aus Kieselschiefer-Ger~llen des unteren Mainstales bei Frankfurt a. M. Geol. Palaeontol., 23:83-99 (in German). Braun, A., 1989b. Eine Radiolarien-Fauna aus dem OberViseum des Dinant-Beckens (Belgien). Geol. Palaeontol., 23:101-111 (in German). Braun, A., 1989c. Unterkarbonische Radiolarien aus Kieselschiefger~llen des Mains bei Frankfurt am Main. Jahresber. Mitt. Oberrhein. Geol. Ver., N.K, 7 l: 357380 (in German). Braun, A., 1990a. Evolutionary trends and biostratigraphic potential of selected radiolarian taxa from the Lower Carboniferous of Germany. Mar. Micropaleontol., 15: 351-364. Braun, A., 1990b. Radiolarien aus dem Unter-Karbon Deutschlands. Courier Forschungsinst. Senckenberg, 133:1-177 (in German). Cheng, Y.N., 1986. Taxonomic studies in Upper Paleozoic Radiolaria. Natl. Mus. Nat. Sci., Taiwan Spec. Pub., l, 311 pp. Coney, P.J., Edwards, A., Hine, R., Morrison, F. and Windrim, D., 1990. The regional tectonics of the Tasman orogenic system, eastern Australia. J. Struct. Geol., 12: 519-543. Crook, K.A.W., 1961. Stratigraphy of the Tamworth Group (Lower and Middle Devonian), TamworthNundle District, N.S.W.J. Proc. R. Soc. N.S.W., 94: 173-188. Deflandre, G., 1952. Albaillella gen. nov. Radiolarie fossile du Carbonif6re inf6rieur, type d'une lign6e aberrante enteinte. C. R. Acad. Sci. Paris, 234:72-84 (in French). Deflandre, G., 1953. Radiolaries fossils. In: P. Grass6 (Editor), Trait6 Zoologlque. Masson, Paris, 1 (2), pp. 389-436 (in French).

J.c. AITCH1SON Fergusson, C.L. and Flood, P.G., 1984. A late Palaeozoic subduction complex in the Border Rivers area of southeast Queensland. Proc. R. Soc. Queensl., 95: 4755. Flood, P.G. and Aitchison, J.C., 1988. Tectonostratigraphic terranes of the southern part of the New England Orogen, eastern Australia. In: J.D. Kleeman (Editor), New England Orogen: Tectonics and Metallogenesis. Univ. New England, Australia, pp. 710. Foreman, H., 1963. Upper Devonian Radiolaria from the Huron Member of the Ohio Shale. Micropaleontology, 9: 267-304. Gourmelon, F., 1987. Les Radiolaires tournaisiens des nodules phosphates de la Montagne Noire et des Pyr6n6es centrales. Biostratigr. Pal6ozo'/que, 6: l - 194 (in French). Hinde, G.J., 1899. On the Radiolaria in the Devonian Rocks of New South Wales. Q. J. Geol. Soc. London, 55: 38-64. Holdsworth, B.K., 1969. The relationship between the genus Albaillella Deflandre and the ceratoikiscid Radiolaria. Micropaleontology, 15 (2): 230-236. Holdsworth, B.K., 1977. Paleozoic Radiolaria: Stratigraphic distibution in Atlantic Borderlands. In: F.M. Swain (Editor), Stratigraphic Micropaleontology of the Atlantic Basin and Borderlands. (Developments in Palaeontology and Stratigraphy, 6. ) Elsevier, Amsterdam, pp. 167-184. Holdsworth, B.K. and Jones, D.L., 1980. Preliminary radiolarian zonation for Late Devonian through Permian time. Geology, 8: 281-285. Holdsworth, B.K. and Murchey, B.L., 1988. Paleozoic radiolarian biostratigraphy of the northern Brooks Range, Alaska. In: G. Gryc (Editor), Geology and Exploration of the National Petroleum Reserve in Alaska, 1974-1982. U.S. Geol. Surv. Prof. Pap., 1399: 777792. Ishiga, H., Leitch, E.C., Naka, T., Watanabe, T. and Iwasaki, M., 1987. Late Devonian Palaeoscenidiidae from the Hastings Block, New England Fold Belt, Australia. Earth Sci. (Chikyu Kagaku), 41: 297-302. Ishiga, H., Leitch, E.C., Watanabe, T., Naka, T. and Iwasaki, M., 1988. Radiolarian and conodont biostratigraphy of siliceous rocks from the New England Fold Belt. Aust. J. Earth Sci., 35: 73-80. Korsch, R.J., 1984. Sandstone compositions from the New England Orogen, eastern Australia: implications for tectonic setting. J. Sediment. Petrol., 54:192-211. McMinn, A., 1982. The age and facies distribution of the Yarrimie and Baldwin formations in the Manilla district. In: P.G. Hood and B. Runnegar (Editors), New England Geology. Univ. New England and AHV Club, Armidale, Australia, pp. 113-120. Nazarov, B.B., 1975. Radiolyarii nizhnego-srendnego paleozoya kazakhstana. Academija Nauk S.S.S.R., Or-

ALBAILLELLARIA FROMTHENEWENGLANDOROGEN,EASTERNNSW dena Trudovogo Krasnogo znameni Geologicheskij Institut Trudy Vyp., 275:1-202 (in Russian). Nazarov, B.B., 1988. Paleozoic Radiolaria. Practical manual of microfauna of the USSR. Nedra, Leningrad, 2, 232 pp. (in Russian). Nazarov, B.B. and Ormiston, A.R., 1985. Evolution of Radiolaria in the Paleozoic and its correlation with the development of other marine fossil groups. Senckenbergiana Lethaea, 66:101-110. Nazarov, B.B. and Ormiston, A.R., 1986. Trends in the Development of Paleozoic Radiolaria. Mar. Micropaleontol., 11: 3-32. Nazarov, B.B. and Ormiston, A.R., in press. New biostratigraphically important Paleozoic Radiolaria of the Soviet Union and North America. In: J.R. Blueford and B. Murchey (Editors), Radiolaria of Giant and Subgiant Fields of Asia. Micropaleontology Spec. Publ., 6. Philip, G.M. and Pedder, A.E.H., 1966. Stratigraphical correlation of the principal Devonian Limestone sequences of Eastern Australia. Proc. Int. Symp. Devonian System. Proc. Alberta Soc. Pet. Geol., Calgary, 2, pp. 1025-1041. Sandberg, C.A. and Gutschick, R.C., 1984. Distribution, microfauna, and source-rock potential of Mississip-

367 pian Delle Phosphatic Member of Woodman Formation and equivalents, Utah and adjacent States. In: J. Woodward, F.F. Meissner and J.L. Clayton, (Editors), Hydrocarbon Source Rocks of the Greater Rocky Mountain Region. Rocky Mount. Assoc. Geol., Denver, Co., pp. 135-178. Schwartzapfel, J.A., 1990. Biostratigraphic investigations of Late Paleozoic (Upper Devonian to Mississippian) Radiolaria within the Arbuckle Mountains. Ph.D. Thesis, Univ. Texas, Dallas. Vickers, M.D. and Aitchison, J.C., 1992. Lower Permian Manning Group: tectonic implications of sedimentary architecture and provenance studies in the Nowendoc-Cooplacurripa area. In: C.F.K. Diessel (Editor), Proc. 26th Annu. Symp. on Advances in the Study of the Sydney Basin. Dep. Geol., Univ. Newcastle, pp. 3137. Wakamatsu, H., Sugiyama, K. and Furutani, H., 1990. Silurian and Devonian radiolarians from the Kurosegawa Tectonic Zone, southwest Japan. J. Earth Sci. Nagoya Univ., 37:159-194. Won, M.-Z., 1983. Radiolarien aus dem Unterkarbon des Rheinischen Schiefergebirges (Deutschland). Palaeont. Abt. A., 182:116-175 (in German, with English abstract).