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Abstract Sedimentary and palaeontological samples from steep, deepwater, escarpments of the Wallaby (`Cuvier') Plateau, a vast marginal plateau with an area of some 100,000km² west of Carnarvon, Western Australia, represent the first collected soft rock geologic data from this immense bathymetric high. The impetus for this frontier, integrated study was to better understand the unresolved geologic history of the Wallaby Plateau, which to date has been hampered by a paucity of real rock data, especially due to difficulties in sampling in 2200 to 5700 m water depths; only modern carbonates, largely altered tholeiitic basalts and volcaniclastic rocks have been recorded previously. Variably fossiliferous to unfossiliferous claystone, siltstone and sandstone samples from 12 southern Wallaby Plateau stations (3015 to 5159 m water depths) range from interpreted paralic to shallow water marine settings, and contain low to moderately diverse assemblages of Bivalvia, Gastropoda, Ostracoda, Foraminifera, palynomorphs, very rare nannofossils, and teleost fish fragments, which collectively point to an age range of latest Berriasian to Barremian-Aptian in the Early Cretaceous that pre-dates, straddles and post-dates the breakup and opening of the Cuvier Abyssal Plain. Seismic imaging of the Wallaby Plateau shows a substantial thickness of both dipping and flat-lying, sub-parallel reflectors beneath parts of the Early Cretaceous Gondwanan break-up unconformity. This information, taken together with the recent identification of Oxfordian-Kimmeridgian foraminifera from the same location, may indicate the presence of pre-breakup sedimentary section beneath parts of the the Wallaby Plateau. Keywords: Systematic palaeontology; Mollusca; Foraminifera; Ostracoda; dinoflagellate cysts; Early Cretaceous; Wallaby Plateau; Australia

While brachiopods from the Devonian of the Canning Basin were first described by Hosking (1933),the only monograph of the fauna is that of Veevers (1959), who also introduced a comprehensive zonation forthe basin. Veevers had at his disposal the earlier collection of Teichert (1949), and the large collections madeby the BMR and WAPET survey parties (see Guppy et al., 1958). The BMR survey also had the benefit of airphotography taken in 1947. Most (but unfortunately not all) of Veevers' localities were marked on the airphotos, which are still held by the palaeontological group of BMR. Veevers quoted air-photo coordinates forhis and the WAPET localities, and I have found these very useful in cross-checking the marked points, wherefield and published numbering systems have diverged. In the process, I discovered several misprints in Veevers'published list. As a recent BMR project to analyse the development of the Canning Basin progressed, it becameapparent that any use of Veevers' brachiopod biostratigraphy was severely limited by uncertainty over the correctstratigraphic position of his localities, in terms of more recently published geological maps (especially Playford& Lowry, 1966). This report is an attempt to address that problem. From all available information, but particularly the air-photos, I have plotted the localities quoted byVeevers onto the current 1:100,000 topographic sheets. Except in areas of little topographic expression thiscould be done with an accuracy equal to that of the map compilations. The results are presented in the firstsection of this report, in which I give as detailed as possible a description of the location of each publishedbrachiopod locality. Coincidentally I have been compiling a catalogue of the BMR holdings of published corals.In the process of providing locality and stratigraphy details I found that there were frequently small discrepanciesfor the heights quoted for localities in measured sections by Hill & Jell (1970) on the one hand, and Veevers(1959) and Veevers & Wells (1961) on the other. I have no way to resolve this, and quote Veevers' figuresherein. I then compared Veevers' published stratigraphic information on the localities against the maps inPlayford & Lowry (1966). These are at the same scale of 1:100,000, although with the old 10,000 yard grid.There were a few topographic discrepancies, but in general this was straightforward. Note was also taken,where possible, of more recent published geological maps (e.g. Druce & Radke, 1979). In making thiscomparison I found relatively few significant changes were needed, other than those resulting from actualchanges in stratigraphic terminology. In the absence of additional biostratigraphic data, I could not generallygo beyond the reassessment of the zonation made by Roberts et al. (1972). However, work on conodont faunasby Nicoll (1980) near a couple of key localities in the Crurithyris apena Zone has led me to establish with someconfidence that that zone must extend into the early Famennian. This partly or completely closes the gapbetween it and the succeeding Nyege scopimus Zone shown by Roberts et al, and is discussed in more detailbelow. Several of the species described by Veevers have since been either fully revised, or at least placed indifferent genera. A few new taxa have also been described. I have brought the results together here in a singlesystematic list, as well as incorporating them in the various lists showing brachiopod distribution, and the tableof zonal distribution.

Exposure of the Horn Valley Siltstone is usually poor, but well preserved material can be obtained from some of the fully cored wells intersecting this interval throughout the Amadeus Basin. In this study, the following cored holes were used: Henbury #4, Henbury #6, Mt Liebig #2, Tempe Vale#1 and Tent Hill #1. I have subdivided the formation into ten informal members, HV1(lowermost) to HV10, which reflect vertical lithofacies variations in a shallow marine shelf environment. These members have been defined primarily from sedimentological and palaeontological information such as the presence or absence of body fossils, mode of preservation, species associations within groups of fossils, presence or absence of bioturbating organisms (trace fossils), lithology and bedding types. It can be inferred that the amount and composition of organic matter preserved in the sediment was determined largely by the concentration of oxygen in the bottom water and the extent to which the sediment was disrupted by burrowing organisms because burrowing and scavenging activities of benthic organisms are controlled by the concentration of oxygen in the bottom water. Organic geochemical data fromTempe Vale #1 and Tent Hill #1 were used to confirm these facies variations. The transition between HV6 and HV7, which can be recognised easily by the sudden change in shale to carbonate ratio, has been found to coincide with the presence of high organic rich sediments, with recorded TOC values of up to 6.30%.

fossils housed in Canberra, and administered by the Australian Geological Survey Organization (AGSO), previouslyknown as the Bureau of Mineral Resources, Geology & Geophysics (BMR). It originated with the appointment of aCommonwealth Palaeontologist in 1927, and since the 1950's has grown from a small collection of about 1,000specimens to its current size of over 30,000 specimens which have been described, figured, or referred to in scientificpublications. The rapid increase in size in recent years reflects a strong research effort to document fossil faunas andfloras from important localities throughout Australia, as well as Papua New Guinea, Australian Antarctic Territory,and the seafloor of our continental shelves. All of these areas have been the subject of geological investigations byAGSO. The CPC forms a taxonomic database which underpins all biochronological dating of AustralasianPhanerozoic sedimentary sequences, and thus forms the basis for biochronological age control using various fossilgroups, which is an integral part of most geological investigations concerned with stratified rocks. Such investigationsinclude geological mapping projects, and subsurface analysis of Australasian sedimentary basins, which areundertaken by AGSO in support of petroleum and mineral exploration and land use activities throughout the continent.