Early Ordovician conodonts from far western New South Wales, Australia

52 Pages·2003·39.6 MB·English

by  Yong Yi Zhen

© Copyright Australian Museum, 2003
Records of the Australian Museum (2003) Vol. 55: 169-220. ISSN 0067-1975
Early Ordovician Conodonts
from Far Western New South Wales, Australia
Yong-yi Zhen1*, Ian G. Percival2 and Barry D. Webby3
1 Division of Earth & Environmental Sciences,
Australian Museum, 6 College Street, Sydney NSW 2010, Australia
y ongyi @ austmus.gov. au
2 Specialist Services Section, Geological Survey of New South Wales,
PO Box 76, Lidcombe NSW 2141, Australia
percivai @ minerals .nsw. gov. au
3 Centre for Ecostratigraphy & Palaeobiology,
Department of Earth & Planetary Sciences, Macquarie University NSW 2109, Australia
[email protected]
Abstract. Thirty species (representing 19 genera) of Early Ordovician conodonts are described and
illustrated from Mount Arrow smith and Koonenberry Gap in the northwestern part of New South Wales.
One new genus, Cooperignathus, and the new species Oepikodus pincallyensis, are established. Acodus
sp. cf. emanuelensis predominates in 35 samples from the Tabita Formation and upper beds of the
underlying Yandaminta Quartzite at Mount Arrowsmith, associated with rami form and pectiniform taxa
including species of Cooperignathus, Prioniodus, Oepikodus, Erraticodon, and Baltoniodus. The
Koonenberry Gap fauna is dominated by coniform species, particularly Protopanderodus nogamii, P
gradatus, and Scolopodus multicostatus. Both faunas span an age range from latest Bendigonian to
Chewtonian (evae Zone); their compositional differences are probably related to slight variations in
water depths and depositional environments. Species endemic to the shallow water Australian cratonic
region, represented by Bergstroemognathus kirki, Triangulodus larapintinensis, Acodus sp. cf.
emanuelensis and Prioniodus sp. cf. amadeus, support a correlation with Early Ordovician faunas of
central and western Australia, particularly those from the lower Horn Valley Siltstone of the Amadeus
Basin. Biogeographically significant species in the western New South Wales faunas include
Cooperignathus nyinti, C. aranda and Scolopodus multicostatus, which provide linkages with counterparts
in North America and South China. Cosmopolitan elements in the documented collections are represented
by Cornuodus longibasis, Drepanoistodus basiovalis, and Scolopodus quadratus. Only one species,
Scalpellodus latus, from Mount Arrowsmith appears to be otherwise confined to Baltoscandia (northern
Europe).
Zhen, Yong-yi, Ian G. Percival & Barry D. Webby, 2003. Early Ordovician conodonts from far western New
South Wales, Australia. Records of the Australian Museum 55(2): 169-220.
author for correspondence www.amonline.net.au/pdf/publications/1383_complete.pdf
170 Records of the Australian Museum (2003) Vol. 55
Fig. 1. Localities and geological maps of the studied areas. Maps of Australia and New South Wales, showing location of Mount
Arrowsmith (B) and Koonenberry Range (C) areas to the north of Broken Hill. B, geological map of the Mount Arrowsmith area
(modified after unpublished mapping by B. Stevens and K.J. Mills, Geological Survey of NSW Broken Hill office), showing locations
of conodont samples collected from the Yandaminta Quartzite and Tabita Formation, Australian Map Grid coordinates from Mount
Arrowsmith 7237 orthophotomap (first edition, 1978). C, map of the Koonenberry Gap area showing locations of samples collected for
conodonts, Australian Map Grid coordinates from Wonnaminta 7336 orthophotomap (first edition, 1978).
Zhen et al.: Ordovician conodonts—western NSW 171
Introduction strata, preserved only on the southwest flank of Mount
Geological setting and previous investigations Arrowsmith, are now included within the Gnalta Group,
while the Lower Ordovician sediments (which are well
Conodont elements, the tooth-like remains of a long-extinct exposed in a syncline west of the Mount Arrowsmith
group of marine animals apparently with chordate affinities, summit) are correlated with the Mootwingee Group.
are abundant microfossils in many Palaeozoic rocks (Sweet, Shergold (1971) and Webby et al. (1981) substituted
1988). Their global distribution and often-restricted time stratigraphic names introduced in unpublished Ph.D.
ranges make them ideal for bio stratigraphic and biogeo¬ research by Warris (1967) to formalize the stratigraphic
graphic studies. During the Early Ordovician Epoch subdivisions introduced by Wopfner (1967). The Cambrian
conodonts ranged widely in shallow seas across the section is faulted against the Lower Ordovician Yandaminta
Australian craton. Conodont faunas of this time from the Quartzite (member E of Wopfner), which is overlain by the
edge of the craton, exposed in far western New South Wales, Tabita Formation (member F) (Fig. 2) and in turn
are here systematically described, enabling precise conformably succeeded by the Pingbilly Formation
correlation with regional and international successions. (Wopfner’s member G). The exact nature of the boundary
The cratonic rocks form part of the Upper Proterozoic- between the Yandaminta Quartzite and the Tabita Formation
Middle Palaeozoic Koonenberry Belt (previously called the is open to interpretation; in most places the contact appears
Wonominta Block, sensu Mills 1992), which trends to be conformable and intergradational, but in some outcrops
southeast from near Tiboburra to between Broken Hill and there is definite evidence of a subtle angular (perhaps
White Cliffs, in the northwestern part of New South Wales structurally induced) relationship (K.J. Mills and R. Glen,
(Fig. 1). In this region of mostly poor outcrop and low relief, pers. comm.). These Mootwingee Group strata unconform-
Koonenberry Belt sediments are generally inconspicuous ably overlie the western belt of the Kara Beds.
or largely buried beneath younger regolith. Mount Pioneering palaeontological and biostratigraphical
Arrowsmith, situated at the northwestern extremity of this studies of the northwestern part of New South Wales were
belt, is a prominent exception, being mainly composed of undertaken by Warris (1967) but much of this work remains
Proterozoic alkaline volcanic rocks—the Mount Arrowsmith unpublished. A brief outline of the fossil distribution at
Volcanics, including basaltic pillow lavas and tuffs— Mount Arrowsmith was given by Warris (1969), who
interposed between an eastern and western belt of provided an insight into the abundance and diversity of the
metasediments (Kara Beds of Mills, 1992), also of probable Early Ordovician faunas, comprising mainly nautiloids,
late Neoproterozoic age. bivalves, gastropods, brachiopods, trilobites, ostracodes,
Wopfner (1967) first described the Middle Cambrian and and conodonts. Only a nautiloid, Anthoceras warburtoni,
Lower Ordovician sediments on the western side of Mount from the Tabita Formation (Crick & Teichert, 1983) and a
Arrowsmith. Wopfner’s mapping has remained the most new species of the problematical genus Janospira, J.
detailed published documentation of the outcrop of these acuosiphon, from the Yandaminta Quartzite (Paterson,
Palaeozoic units, although his informal stratigraphic 2001a) of this rich fauna have previously been formally
nomenclature has been updated. The Middle Cambrian described.
Section TAB1
Fig. 2. Stratigraphic sections through the Lower
Section Y4
Ordovician successions at Mount Arrowsmith, western
172 Records of the Australian Museum (2003) Vol. 55
Conodonts from a single sample (16 specimens) collected Early Palaeozoic regional geography
from the basal beds of the Tabita Formation were first
Following the Delamerian Orogeny in Middle-Fate
identified by E.C. Druce (in Wopfner, 1967: 168,170), who
Cambrian time (Q.Z. Wang et al., 1989, fig. 3), the Fower
established a possible upper “Arenig” age and noted
Ordovician Mootwingee Group was deposited on the Gnalta
similarities with the conodonts of the Horn Valley Formation
Shelf, as part of the east-facing margin of the Australian
in the Amadeus Basin. Independent identifications of the
craton, which represented also the eastern edge of the
same form genera determined by Druce, together with many
Gondwanan supercontinent. Webby (1976, 1978, 1983)
additional form taxa, were made by Warris (1967) in a major
interpreted quartzose clastic sedimentation, which
study of the Mount Arrowsmith conodonts, based on
dominates much of the Mootwingee Group to the south of
collections of nearly 4500 identifiable specimens obtained
Koonenberry Mountain, as derived from the Delamerian
from three measured sections in the area. In his published
uplands to the (present) southwest, and deposited in an
listing of the Mount Arrowsmith fauna, Warris (1969)
extensive delta. Broadly contemporaneous impure
emphasized forms not found in the solitary sample analysed
carbonates in the Tabita Formation at Mount Arrowsmith,
by Druce and noted the presence of five new species of
and dolomitic limestones at Koonenberry Gap, are the only
“fibrous” genera from throughout the Tabita Formation.
known remnants preserved of what might have been an
Warris also recognized three biostratigraphically distinct
extensive shallow shelf depositional setting extending to
conodont zones in the formation, the lower two of early
the northwest (Webby, 1976, fig. 6B; 1983, fig. 1).
“Arenig” age, and the upper one of late “Arenig” age. Jones
Environments probably ranged in water depth from
et al. (1971), in a brief reference to the Mount Arrowsmith
strandline to sub wave base, in relatively sheltered situations
conodonts, interpreted their age as broadly mid to late
such as protected bays or very shallow gradient shorelines,
“Arenig”. Further studies of the Warris conodont collection
inferred from complete preservation of diverse macrofossils
were undertaken by Kennedy in the 1970s, but the revised
in the Tabita Formation. There is no convincing evidence
systematics employing a combination of apparatus and form
of areas with restricted circulation or enhanced salinity,
species taxonomy remains unpublished (Kennedy, 1976).
except that numerical dominance in the Tabita samples of a
Repeated requests for the return of the Warris collection to
single species (Acodus sp. cf. emanuelensis, Fig. 4) may
Australia have been ignored, so the original material remains
indicate some sort of specialized environment. Any
unavailable for study. Accordingly, we have not relied on
differences in faunal content between localities of essentially
Kennedy’s (1975) listing of 16 taxa from the area, nor have
the same age are therefore most plausibly related to variation
we referred to his now mainly outdated thesis research.
in water depth.
Our study of conodonts from Mount Arrowsmith
Elsewhere on the Australian craton at this time, the
commenced in 1999 as part of a broader program of research
Farapintine Sea provided a shallow marine connection
on the Early Ordovician biotas of western New South Wales.
linking the Gnalta Shelf through the Amadeus and Georgina
Conodont resampling focussed on a number of measured
Basins westwards to the Canning Basin (for discussion on
sections and spot localities in the Yandaminta Quartzite and
the development of this concept refer to Webby, 1978: 55).
the Tabita Formation (Fig. 2). Recovery of 3076 identifiable
Contemporaneous conodont faunas in the central Australian
elements substantially increases knowledge of the fauna,
basins have been described from the Horn Valley Siltstone
enabling for the first time an accurate age determination
of the Amadeus Basin (Cooper, 1981; Nicoll & Ethington,
and correlation of the succession with others in Australia
in press; Stewart & Nicoll, in press), and the Coolibah
and elsewhere in the world.
Formation of the Georgina Basin (Stait & Druce, 1993).
The Koonenberry Gap area, some 80km to the east of
The known Canning Basin faunas are both slightly older
Mount Arrowsmith (Fig. 1), has received much less
(late Fancefieldian-Bendigonian: McTavish, 1973; Nicoll
palaeontological attention. Packham (1969: 68) mentioned
et al., 1993) and younger (Darriwilian: Watson, 1988) than
limestones at Koonenberry Mountain from which the late
those from western New South Wales. Compositional
Brian Daily (University of Adelaide) had identified a small
differences in conodont faunas from these regions can be
conodont fauna of late Early Ordovician or early Middle
interpreted as due in part to water temperature variations,
Ordovician age; it is not certain whether this sample was
as cooler, more temperate waters entered the Farapintine
collected from the section exposed at the Gap. The
Sea from the Canning Basin side to mix with warm
prominence of Koonenberry Mountain above the surround¬
equatorial currents flowing across the Gnalta Shelf. Focal
ing flat plains is due to the northwest-southeast trending
variations in faunal distribution are more likely due to water
Koonenberry Fault with uplift delineating the west margin
depth fluctuations, as discussed below.
of the mountain, while a subparallel splay of this fault forms
its east boundary. Webby et al. (1988) described a trilobite
Conodont ecology and biogeography
fauna of latest Cambrian-basal Ordovician (Tremadocian)
age from siltstones of the Watties Bore Formation, adjacent Among the 30 species recorded from the Mount Arrowsmith
to the faults. Well-bedded dolomitic limestones (strati¬ area, 20 (including nearly all those with relatively restricted
graphic unit not yet formalized) at Koonenberry Gap have age ranges) were also found in the Koonenberry Gap
previously yielded the conodont Bergstroemognathus samples (Fig. 5), and hence these two assemblages are
kirki (Zhen et al., 2001). The conodont fauna from considered more or less contemporaneous in age. There are,
Koonenberry Gap (determined from 446 identifiable however, some significant differences between their overall
specimens), like the Mount Arrowsmith assemblages, is faunal composition, diversity, and relative abundance. For
of evae Zone age (late Bendigonian-Chewtonian), example, the fauna from the Tabita Formation at Mount
broadly equivalent to the middle “Arenig” or uppermost Arrowsmith is the more diverse, including coniform,
Ibexian (Webby, 1995, fig. 1). ramiform and pectiniform elements, while the Koonenberry
Zhen et al.: Ordovician conodonts—western NSW 173
56 vo oo vo vo 4 r->
Total 15 CCOO 'OInt V(NO oo OV © 20oo m CO OCOO d- OO r- OV oo _! vOoV vo i-~ C<NO oo <N CO CO vo (N CO d- d- <N ot- oCO ((NN OO
11 C1613 c<No i <N CO OO (N - m (N 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 <N - - 1 1
C1612 d" i 1 1 (N - 1 1 - 1 - - I 1 1 - - 1 1 - 1 1 1 - 1 - 1 1 1 - m CO (N 1
oa§3 ^<sd 0611 CO <N <N 1 - 'It - 1 CO (N 1 1 vo I (N 1 co 1 - 1 1 1 1 1 CO - 1 - 1 1 - 1 d- - - (N
T2 - 1 1 - ! 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
~ U
6 6 TAB 1/128.8 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
<2 8
^ Sh
T3 TAB 1/125.4 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
a -5
c3 "S
TAB 1/111 CO 1 (N - 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 - 1 1 -
TAB 1/103.8 CO 1 CO 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 - - 1 1 -
a in
TAB 1/91 in 1 1 1 (N - 1 (N 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
<§ c* TAB 1/86.7 O(Nn CO m - vo o CO 1 d- 1 1 1 I 1 1 1 - 1 1 - 1 1 1 1 1 1 1 1 d- - (N -
TAB 1/83 1 1 1 1 1 1 1 1 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
11<u TAB 1/78.2 OCOv <N © - oo VO m 1 r- (N 1 - I 1 1 - 1 1 1 1 1 1 1 1 1 1 (N co (N - 1
03 X>
C -2 TAB 1/65.2 m - 1 1 CO - 1 1 1 1 I 1 1 1 in 1 1 - (N - - (N 1 - - 1 1 1 m (N - (N
O a,
•0a433 sSc3h TAB 1/44.5 CO - - 1 1 - 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
O N TAB 1/39.5 VCOO VO oo m VO CO CO CO (N 1 1 1 I 1 1 1 (N 1 1 1 - - vo (N 1 d- 1 1 1 in (N - - 1
CL, t5
jS § TAB 1/31 1 1 1 1 ! 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
3 O'
[2 ?s TAB 1/30.7 - 1 - 1 ! 1 1 1 1 ! 1 1 1 1 1 ! 1 1 1 1 1 1 1 1 1 1
^.a
.s a TAB 1/13.7 vo - - 1 - 1 (N 1 - - 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 - 1 1 1 1
a
(cid:9632)si TAB 1/8.1 odv- oo (N <N oo m d- m in - 1 1 1 1 1 1 1 - 1 1 1 1 - 1 1 1 1 1 1 <N CO - - -
o >- M/A7 <ONn d" (N - in 'cl- d- oo d- 1 d- <N 1 1 1 1 1 odo- vo vo in in \D o vo 1 1 co -H CN 1 d- m <N (N -
il
(cid:9632)g = M/A4 din" o l> t" (N in o d- (N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 - 1 1 1
0<3o 'S<D M/A3 r<N- 'It vo CO CO d- (N co <N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-7 'it - <N 1 1 1 1 1 - 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 - 1 1 -
<u
'1 M/A 11-6 (N - (N 1 <N <N (N - (N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 (N (N 1 1
oa<u M/A 11-5 Odnj <N OCOO (N O(NO OO VO o in 1 1 (N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 - - 1 1
M/A 11-4 in - - - 1 (N 1 1 1 - 1 (N - 1 1 1 1 - 1 1 1 1 ! ! 1 1 1 1 1 1 1
M/All-3 'ri-t OO m'it (N i(Nn vo i(Nn vo <N vo 1 - o(N CO vo 1 (N vo CO - 1 1 - 1 1 1 oo (N (N (N — 1 <CNO <N 1
M/A 11-2 d<N- <N VO CO CO d- (N <N <N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 d- <N - - 1
M/All-1 <N <N <N 1 - co CO 1 - - 1 1 1 1 1 1 1 1 - 1 1 1 - 1 1 1 1 1 1 1 1 1 1
Y4-8 t(N- - m 1 F" d- VO 1 d- - 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CO (N - - 1
Y4-7 v<No vo CO 'it o(No ov <(NN (N O(N - 1 d- 1 1 1 1 1 - 1 1 - 1 1 1 1 1 1 1 - d- - (N -
Y4-6 '<<iNNt m (mN vo iCnO m(N iCnO O O<Nn <N 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 VD CO (N -
Y4-4 mm oo On (N o oo r- co OO 1 1 1 'd- - 1 1 (N - 1 1 1 1 1 (N - 1 1 1 - (N 1 1 1 1
Y4-3 o(N <N CO CO CO CO (N - CO 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CO - - 1 1
Y4-2 m'<iNt CO m VO ''iitt o<No O(NO 0 od- 1 1 (N 1 1 1 1 1 (N 1 - 1 - 1 - 1 1 - 1 o(No CO (N (N
Y4-1 On <N 1 1 1 1 (N d- 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 ! 1 1 1
W5 'it IN o <N ["- (N CO vo d- 1 1 in 1 1 - 1 d- vo 1 1 CO - - (N 1 - - 1 1 in OO (N (N d-
Y1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
dus emanuelensis sp. cf. (total) CL XPtH) <sN s 0003 X00) 0o0 ©00 Acodus sp. (S elements) Acodus jemtlandica (total) Baltoniodus sp. A (total) ergstroemognathus kirki (total) CaL £2 0003 x0>0 0o0 ©00 Cooperignathus nyinti (total) C0L3 XCL> s 0003 X00> 0o0 Cooperignathus aranda (total) CaL XCL> s 0o03 X00> 0o0 Cornuodus longibasis (total) Drepanodus sp. (total) arcuatiform graciliform sculponeaform
o B
c
A
174 Records of the Australian Museum (2003) Vol. 55
p CN
Total m oo CcNn vCNo CmN OCNs OCNs ^t ^t PCN cCNn ^t Os CcNn o'Iot ocn m'it Ocn m so pm in CN P SO ionv cn - p p P
0613 (N cn 1 cn m - 1 l 1 1 1 1 - 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
0612 m 1 1 - - cn (N cn cn 'Ct CN 1 1 m 1 1 - - (N - 1 1 1 1 1 OO OO I I 1 1
0611 'ct 1 1 1 CN CN OO cn CN 1 cn 1 1 1 1 1 1 1 1 cn CN -H 1 1 1
T2 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1—H 1 1—H
TAB1/128.8 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1—H 1—H 1
TAB1/125.4 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CN 1—H 1—H
TAB 1/111 i 1 1 1 1 1 1 1—H 1—H 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB1/103.8 i 1 1 1 1 1 1 cn 1 1 (N 1 1 1—H 1 1 1 1 1 1 1 1 1 1 1
TAB 1/91 i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/86.7 cn 1 1 vo cn 1 1 so cn CN ^1- ^1- 1 1 1 1 1 1 1 1 1 1 1
TAB 1/83 1 1 1 1 1 1 1 1 1 CN 1 1 1 1 - - 1 1 1 1 1 1 1 1 1 1 1
TAB 1/78.2 VO (N oo (N cn (N 1 (PN (N cn in p cn SO 1 1 1 1 1 (N (N 1 1 in
TAB 1/65.2 l 1 1 1 1 1 1 1—H 1 1 1 1—H 1 1 1 1 1 1 1 1 1 in 1—H 1—H in cn
TAB 1/44.5 l 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/39.5 1 cn 1 1 CN -H 1 1 1 1 1 1 1 1 1 1 1 1 1 1 in CN
TAB 1/31 l 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/30.7 l 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 CN -H
TAB 1/13.7 l 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/8.1 CN 1 1 1 - - ^1- 1 - - - - 1 1 1 1 1 1 1 1 1 1 - - 1 1 - - 1 1 1
M/A7 ^t 1 cn CN m 'It X 1 cn - CN OO - CN CN 1 CN - ^|- 1 1 1 1 OO CN - P cn cn
M/A4 'it 1 1 - CN - CN - - 1 1 S(NO CN in m cn in CN 'It 1 1 1 1 1 CN CN 1 1 1 1
M/A3 1 1 1 1 1 1 1 1 1 cn 1 1 1 -H 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-7 1 1 1 1 1 (N -H 1 1 SO 1 cn cn CN cn 'Ct 1 1 1 1 1 1 1 1 1 1 1
M/A 11-6 cn 1 1 1 CN - cn 1 1 - - - 1 in 1 - - CN cn CN SO 1 1 1 1 1 1 1 1 1 1 1
M/A 11-5 vo 1 1 - cn CN oo - 1 cn CN CN 1 ^t CN 1 - cn 'it CN CN - 1 1 - 1 - cn - - 1 -
M/A 11-4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-3 ^|- 1 'Ct in 'Ct -H 1 1 (^N|- £ m CN p OV ^|- 1 1 1 1 1 1 1 1 1 1 1
M/A 11-2 'Ct 1 1 1 CN CN 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 -H 1 1
M/All-1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Y4-8 © - 1 'it 'it - vo cn 1 - CN 1 1 ^CNt 'It - m - cn 'It X 1 1 1 1 1 1 1 1 1 - 1
Y4-7 p - - CN CN - O 1 - cn CN 'Ct 1 s(No P 'Ct - - cn 'Ct SO 1 1 1 1 1 1 1 1 1 1 1
Y4-6 CN 1 in CN cn CN cn CN - m CN cn 1 cpn in £ in oo 'CCNt Os 1 1 1 1 1 1 1 1 1 (N (N 1
Y4-4 OV CN - CN 'it 1 1 1 - SO cn 'it CN CN - CN CN 1 1 1 1 1 1 1 1 1 - - 1
Y4-3 CN 1 - 1 - 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Y4-2 CCNN X o 1 m -H 1 1 cn 1 1 1 1 1 1 1 1 1 1 1 1 1 1 icnn SO p (N SO
Y4-1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
W5 'it - - cn CN - - 1 ^1- 1 1 1 1 1 1 1 1 1 1 1 1 1 1 cn - -
Y1 (N 1 1 1 1 CN 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
7o3 CP s 0003 x00 0O0 3o s 0003 x00 0o0 XC/3 3o 7o3 CP d s 0003 X00 0O0 X00 0(O3 =&ht xfLi Wo SUP -oO^ sodPSnX O0O3 O0o3 cdt XPh s 0003 X00 otal) otal)
d -S < "§ p. (tus (t
OCoC=D3 pp PpSpS (cid:9632).§a5In ^op2 "pIpd<sp§Xl PCsP§PSso ^^'1sI^^ss P^'-23scdSs3 Oneotodus ss sp. cf. amade
p G Q du
P d o 'S, o
d o oni
ri
P
Zhen et al.: Ordovician conodonts—western NSW
o
Total Ol- CN OCN CCOO oCOo VO CO CN CO CN oo iCnO VO CoD l"- in o CN OCNC co <N Ov O O co (N
0613 1 <N 1 1 H 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I Tl- (N IT) VO (N I
0612 1 C<NO - VO Ov O 1 1 1 1 CN CCNN CN o'It 1 1 1 1 1 | OhOCKN
0611 1 VO 1 CN CO 1 1 1 1 VO CO CO oo 1 1 1 1 1 M m (N m ^ ^
T2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/128.8 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/125.4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/111 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/103.8 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/91 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/86.7 1 1 1 1 1 1 1 1 1 1 1 1 1 CN 1
TAB 1/83 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/78.2 1 ol- CN CO ol- in 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/65.2 1 1 1 1—H 1 £ 1 1 1 1 1 1 1 1 1
TAB 1/44.5 1 1 1 1 1 1 1 1 1 1 ! 1 1 1 1
TAB 1/39.5 1 1 1 1 1 1 1 1 1 1 1 1 1 H 1—H
TAB 1/31 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/30.7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/13.7 1 1—H 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
TAB 1/8.1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 co (N m co co
M/A7 1 1 1 1 1 1 1 1 CO CO oo CN m 1
M/A4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A3 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-7 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-6 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-5 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-4 1 1 1 1 1 1 1 1 1 1 1 1
M/A 11-3 1 VO 1 CO 1 CO CN -H 1 1 1 1 1 CN 1 CN -H |
M/A 11-2 1 CO 1 1 -H CN 1 1 1 1 1 1 1 1 1 1 1 1 ov <N CO <N <N I
M/All-1 1 Ov CO - CN CO 1 1 1 1 1 1 1 1 1 1 CO 1 CD (N <N ''t CD
Y4-8 wo 1 - - CO - 1 - 1 1 1 1 1 1 1 CN 1
Y4-7 1 1 1 1 1 1 1 1 1 1 1 1 1 1
Y4-6 -H 1 -H 1 1 1 1 1 1 1 1 1 1 't 1
Y4-4 1 Ov - CN CO CO ! 1 1 1 1 1 1 1 1 1 CN 1 co i> m vo oo 'f m
Y4-3 1 1 1 1 - 1 1 - 1 1 1 1 1 1 1 1
Y4-2 CO Ov CO VO CD - 1 1 - CO 1 1 - CN CN CN 1 OO I ol- (N -h (N
Y4-1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
W5 1 o 1 Ol- Ol- CN 1 1 1 1 1 1 1 1 1 1 - 1
Y1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
3 3 0003 o0>0 0o0 T003 3 0003 0030 0O0 C0D3 £ 0003 0o0 T003 3 Pb M o0I000-'- y/—cv OC*D'. 0003 £00) 0U0 U00 Oc3 Psh ^PD3 0003 X003 0O0 T00J al)
o o o o +o o Jo~“ O ot
00 a s (t
<1 a u
C=D3 "T&t(cid:9632)XOoo3 aQ<^50 <SO3 a<aa*n50 a•?(cid:9632)aoso2 -~-22a quadrat
U_CoW ) •n^5- <S. 3JaIvaS<s3i -"fa£aaaa ""I2aaai •O£a£2h2 ~oaaSo £a"2(cid:9632)aaaoas Scolopodus
S 2 s CO
176 Records of the Australian Museum (2003) Vol. 55
Gap fauna is dominated by robust coniform elements.
Total 302 CO (mN CCOO VO VinO VO Oov 3522 Particularly noticeable is the absence of Oepikodus
pincallyensis, Prioniodus sp. cf. amadeus, Prioniodus sp.
0613 oo l 1 m 1 CN 1 oCO 1 OOON A and Baltoniodus sp. A from the Koonenberry Gap fauna.
0612 oo l VO <N - CN 1 CCNO 1 toCoM Furthermore, approximately half the total number of
0611 r- l 1 CO VO i> 1 1 co elements recovered from Mount Arrowsmith samples can
be assigned to just one species, Acodus sp. cf. emanuelensis
T2 1 l 1 1 CM
(Figs. 3, 4), whereas this species is much less common in the
TAB 1/128.8 1 l 1 1 -H Koonenberry Gap samples. In the latter, Protopanderodus
TAB 1/125.4 -H l 1 1 co nogamii is the dominant species (nearly 30% of the fauna),
while in the Mount Arrowsmith fauna, this species is very rare
TAB 1/111 1 l 1 1 to
(Fig. 3). Triangulodus sp. A, Scolopodus multicostatus, and
TAB 1/103.8 1 l 1 1 oo Protopanderodus gradatus are also relatively abundant at
TAB 1/91 vsD CN - (N 1 1 - 1 1 1 £ Koonenberry Gap compared to Mount Arrowsmith (Fig. 4).
TAB 1/86.7 m - 1 CN 1 CN I 1 1 1 NO Such compositional differences between the conodont
faunas of the two localities probably reflect biofacies
TAB 1/83 1 1 1 1 1 1 l 1 1 1 CM
variations. Johnston & Barnes (1999), in a study of
TAB 1/78.2 v(No 'it vo CO (N m ^i- CN 1 1 ON contemporaneous conodont faunas of western Newfound¬
TAB 1/65.2 'it 1 - (N - 1 1 1 C0O0 land, recognized a Diaphorodus biofacies that represents a
shallow-subtidal environment. Diaphorodus is here
TAB 1/44.5 1 1 1 1 1 1 CO
regarded as a junior synonym of Acodus—see Zhen et al.
TAB 1/39.5 1 1 1 1 1 NcoO (in press). The domination of A. sp. cf. emanuelensis at
TAB 1/31 <N 1 1 - - 1 CM Mount Arrowsmith suggests that the western New South
TAB 1/30.7 - 1 1 - 1 Wales faunas generally inhabited a similar shallow-subtidal
environment. However, the presence of O. pincallyensis and
TAB 1/13.7 cn 1 1 1 1 CN - 1 1 1 to several species of Prioniodus, in association with abundant
TAB 1/8.1 o<N - 'it CN CN Ov t" CN OO 1 CCMM sponge spicules in some samples of the Tabita Formation,
M/A7 VcnO VO OO 'it oo 'it CN - 1 COMN suggests interfingering of a somewhat deeper subtidal
biofacies. In contrast, the absence of deeper water forms
M/A4 m - 1 - - (N 1 1 1 ^OtN-
such as species of Oepikodus and Prioniodus from the
M/A3 1 1 1 1 1 1 1 oco Koonenberry Gap fauna, together with the abundance of
M/A 11-7 1 1 1 1 1 1 1 cCMn robust coniform elements, probably indicates the presence
M/A 11-6 Ov - - CO CN CN 1 1 1 ^1" of shallower, near-shore conditions in that area.
Bergstroemognathus kirki, Triangulodus larapintinensis,
M/A 11-5 cn - - - 1 1 1 1 1 OOn Acodus sp. cf. emanuelensis and Prioniodus sp. cf. amadeus
M/A 11-4 1 1 1 1 1 1 1 1 cn were probably endemic to Australia. Numerically, these four
M/A 11-3 VO - 1 t" (N CO CN 1 1 cCMn species constitute slightly more than half of the western
M/A 11-2 CO - 1 1 - - 1 1 1 1 cton New South Wales faunas. They are widely distributed in
the intracratonic basins of Australia, typically (except for
M/All-1 Ov CO 1 1 - CN CO 1 1 1 to P. sp. cf. amadeus) inhabiting shallow water environments
Y4-8 CCOO 'it CN in i> t" in CO - 1 00 (Cooper, 1981; Stait & Druce, 1993). Accompanying
Y4-7 'CiNt in CO 'it - in 'it CN - 1 C^1M- Dcorsempaonpooilsittaond ussp ebcaiseiso, vianlcislu, dSincgo loCpoordnuuso dquusa dlornatguibs aasinsd,
Y4-6 CO <N CN CO CO <N - 1 1 1 tcConO Ansella jemtlandica, together comprise only a minor
Y4-4 Ov - - 1 - CN CO - 1 1 NoO component (about one-tenth) of the Mount Arrowsmith and
Y4-3 m - CO 1 1 1 1 - 1 1 cCnO Koonenberry Gap faunas.
Domination of endemic taxa in the cratonic shelf of
Y4-2 Ov VO CN CN 'it - CN CN 'it 1 cn
western New South Wales is in striking contrast to the
Y4-1 1 1 1 ! ON composition of deeper water faunas inhabiting offshore parts
W5 1 1 1 ! - § of the Gondwanan margin; for example, the conodonts of
the Hensleigh Siltstone (elegans Zone) in central New South
Y1 1 1 1 1 1 1 1 1 1 1 IN
Wales where cosmopolitan and widespread species are
7o3 CLh Oh s 0003 o0>0 0o0 T003 e<u 7o3 Total coovrerrewlahteinlmg ifnagulnya sd ofrmomin atnhte (cZrahteonn iect apll.a, tf2o0r0m1 ,a innd p mreasrsg)i.n Isn,
those non-endemic species which are not long-ranging
o
cosmopolitan forms, assume critical importance. These
ued. C<O OC3/5h comprise the remaining third of the western New South
n ais Wales shelf margin fauna, with many exhibiting particularly
onti a important biogeographic relationships (discussed below).
C Cooperignathus nyinti and C. aranda are widely
-2
Fig. 3. -e2 "stsQsoo. bdeisitnrigb urteepdr einse Antuesdtr ailnia nS ocurathto nCich insuac c(Aesnsi,o n1s9,8 a7s) , wNelol rtahs
American Midcontinent successions (Ethington & Clark,
Zhen et al.: Ordovician conodonts—western NSW 111
50-
a (cid:9632) total faunas (B+C) A.cf.em. Acodus sp. cf. emanuelensis
E.patu Erraticodon patu
b H Mt. Arrowsmith fauna T.lara. Triangulodus larapintinensis
D.basi. Drepanoistodus basiovalis
40- c Koonenberry Gap fauna
S. multi. Scolopodus multicostatus
P.nog. Protopanderodus nogamii
Corn.l. Cornuodus longibasis
P.grada. Protopanderodus gradatus
®30
eg O.pinc. Oepikodus pincallyensis
c D. costa. Drepanoistodus costatus
0
o T. sp. A Triangulodus sp. A
O Coop.n. Cooperignathus nyinti
D_ 20-
18 spp. other 18 species
Jl
10-
A.cf.em. E.patu T.lara. D.basi. S.multi. P.nog. Corn.l. P.grada. O.pinc. D.costa. Tsp.A Coop.n. 18 spp.
Fig. 4. Bar charts illustrating relative species abundances in the Lower Ordovician conodont faunas of western New South Wales.
1982; Repetski, 1982) and in peri-Laurentian offshore Ordovician age in the Langkawi Islands, Malaya (Igo &
deeper water successions (Pohler, 1994; Johnston & Barnes, Koike, 1967). Also, in the Argentine Precordillera, Serpagli
2000). They are not only biostratigraphically significant due (1974) recorded P. nogamii in a post-evae zone occurrence.
to their short stratigraphic range, but are also valuable Elements of typical Baltoscandian faunas are represented
biogeographically in establishing links between eastern only by Scalpellodus latus, which is a minor component of
Gondwana and Laurentia. Erraticodon patu has been the Mount Arrowsmith fauna. This species was also recorded
reported from North America (Nowlan, 1976; Bauer, 1990), from the Horn Valley Siltstone of the Amadeus Basin
the Argentine Precordillera (Lehnert, 1995) and western (Cooper, 1981).
Argentina (Albanesi & Yaccari, 1994), although some of
these assignments have doubtful validity (see later Biostratigraphy and regional correlation
discussion). Scolopodus multicostatus is also widely
distributed in Australian cratonic successions, and in North Given that the most abundant species in the faunas under
American Midcontinent successions such as the St. George discussion are confined to Australia (Figs. 4, 5), it is not
Group, Newfoundland (Barnes & Tuke, 1970) and the surprising that their precise age determination and
Fillmore Formation (zone G2) of the Ibex area, Utah international correlation are difficult. Zonal index species
(Ethington & Clark, 1982). of neither the North Atlantic nor North American
Jumudontus gananda, Drepanoistodus costatus, Midcontinent biostratigraphic successions are recognizable
Protopanderodus gradatus, P. leonardii and Protoprioni- in the western New South Wales conodont faunas. However,
odus yapu were widespread species, occurring in Australia, co-occurrence of Oepikodus communis, Cooperignathus
peri-Gondwanan blocks (including South and North China), nyinti, C. aranda, and Jumudontus gananda in the Tabita
the Argentine Precordillera, and in Laurentia. However, Formation suggests a latest Bendigonian to Chewtonian age,
these species have not been recorded in typical North corresponding to the evae Zone of the North Atlantic faunal
European (Baltoscandian) successions, except for doubtful scheme, or the andinus to aranda zones (top Ibexian) of
occurrences of P. gradatus from a higher stratigraphical the North American Midcontinent succession. No evidence
interval (variabilis Zone to E. lindstroemi Subzone) of the exists in these Tabita Formation faunas to support the earlier
Mojcza Limestone in the Holy Cross Mountains, Poland contention of Warris (1969) that the formation spanned three
(Dzik, 1994), and from a lower stratigraphical level (middle conodont zones.
P. proteus Zone) in central Sweden (Lofgren, 1994). Within the Australian craton, the Mount Arrowsmith and
Protopanderodus nogamii, the dominant species in the Koonenberry Gap conodont faunas correlate well with the
Koonenberry Gap fauna (Figs. 3, 4), is widely distributed Horn Valley Siltstone fauna of the Amadeus Basin, central
in North China, South China, Korea, southeast Asia, Australia, for which Cooper (1981) suggested an age ranging
Australia, and the Argentine Precordillera. In North China, from the Oepikodus evae Zone to Baltoniodus navis/
this species had a relatively long range (An et al., 1983; triangularis Zone. While this age assignment remains
Chen et al., 1995) with its earliest appearance in the acceptable, presence of the index species O. evae and B. navis
Beianzhuang Formation (Chewtonian to Castlemainian cannot be confirmed in the Horn Valley Siltstone, based on
equivalents, evae to originalis zones), extending up into Cooper’s illustrated specimens. Re-examination of a large
the early Late Ordovician Fengfeng Formation. The species topotype collection of the Horn Valley specimens, provided
is known from the basal Setul Limestone of possibly Early courtesy of Dr Barry Cooper, has also failed to reveal these
178 Records of the Australian Museum (2003) Vol. 55
Fig. 5. Comparative distribution of the Early Ordovician conodont faunas from western New South Wales (reference sources: central
New South Wales, Hensleigh Siltstone, Zhen et al., in press; Amadeus Basin, Horn Valley Siltstone, Cooper, 1981; Georgina Basin,
Coolibah Formation, Stait & Druce, 1993; Canning Basin, Emanuel Formation, McTavish, 1973, Goldwyer & Nita formations, Watson,
1988; Argentine Precordillera, San Juan Formation, Serpagli, 1974, Lehnert, 1995, Albanesi, in Albanesi et al., 1998; San Rafael,
western Argentina, Ponon Trehue Formation, Lehnert et al., 1998; Newfoundland, Cow Head Group, Pohler, 1994, Johnston & Barnes,
1999, 2000; eastern New York, Landing, 1976; Ibex area, Utah, Ethington & Clark, 1982; Franklin Mountains, southern New Mexico,
El Paso Group, Repetski, 1982; Hebei Province, North China, Beianzhuang Formation (Lower Majiagou Formation), An et al., 1983;
Ordos Basin, North China, An & Zheng, 1990; South China, Dawan formation and equivalents, An, 1987, Wang, 1993; east and north
Greenland, Smith, 1991; Sweden, van Wamel, 1974, Lofgren, 1978, 1999).
AUSTRALIA ARGENTINA N. AMERICA CHINA
X
<sa§ao£a XoZ0t<a<ooDD3 ZsOa _P<03C0aa3D33 _Oat00aSo<aoD33P "Uaac0aa0ao33 VOOa<oahD <tZ+000oH33) xTJ3za<a£3D za£L£<Dh _ao2aa05oah3 Dcac!<*D33: 3"uXza0a<SD3 PocOLQnh _XUX00oa0a3 ZoQ<azaaa 0zaQa£0
• • •
Acodus sp. cf. emanuelensis • • -
Acodus sp. • • • • • •
A
Amelia jemtlandica
- - - - - - - - - -
Baltoniodus sp. A • • .•w •
Bergstroemognathus kirki • • _ • • • • •
Cooperignathus nyinti • • - • - - • - • • - - •- - -
Cooperignathus aranda • • •- • - - •- • •- •- •- • - •-
Cornuodus longibasis • • - - - - -
Drepanodus sp. • • • • • • • • • •
Drepanoistodus basiovalis • • - • •- • • ? - - •- •- •-
Drepanoistodus costatus • • - - - - - -
Drepanoistodus sp. • • •
Erraticodon patu • -
Erraticodon sp. A • • • • • • • • • •
Jumudontus gananda • ? ? - •- • • •- • - - • -
Oepikodus communis • - - - - - - —
Oepikodus pincallyensis n.sp.
Oneotodus sp.
Prioniodus sp. cf. amadeus
Prioniodus sp. A
Protop anderodus gradatus
Protopanderodus leonardii
Protopanderodus nogamii
Protoprioniodus yapu
• • • • •
Scalpellodus latus
• • • - • • • • • • • • • • • •
Scolopodus multicostatus
Scolopodus quadratus
Triangulodus larapintinensis
Triangulodus sp. A - - - - - - - - - - - - - - - --
Ulrichodina sp. cf. simplex
total species in common
with Mount Arrow smith 20 5 17 66 11 3 11 46946775
two species. Nicoll & Ethington (in press) recognized a new Correlation of the Mount Arrowsmith and Koonenberry
species of Oepikodus, apparently closely related to O. Gap faunas with those of the Coolibah Formation of the
communis, occurring in the Horn Valley Siltstone. In the Georgina Basin (Stait & Druce, 1993) is based on co¬
Tabita Formation, O. communis is extremely rare, whereas occurrence in both regions of Bergstroemognathus kirki,
O. pincallyensis (a transitional form morphologically Cooperignathus nyinti, C. aranda, Drepanoistodus costatus,
between O. evae and O. communis) is relatively abundant. Protopanderodus nogamii, Scolopodus multicostatus and
The stratigraphic range of O. communis extends upwards Triangulodus larapintinensis (Fig. 5). Of the three
at least to the base of the flabellum/laevis Zone (Sweet, bio stratigraphic associations recognized by Stait & Druce
1988), and indeed, Cooper (1981) recorded Microzarkodina (1993), the western New South Wales faunas are most
flabellum from the upper part of the Horn Valley Siltstone. closely aligned with those of the middle Coolibah
However, M. flabellum has not been recognized in the Formation, where the first appearances of C. nyinti, C.
western New South Wales conodont faunas, suggesting that aranda and T. larapintinensis occur. These species also
strict equivalence of the Tabita Formation is with the lower range into the upper bio stratigraphic association in the
part of the Horn Valley Siltstone (Fig. 6). Coolibah Formation. Although Stait & Druce (1993)