Total contribution of six recently discovered submerged coral reefs in northern Australia to Holocene neritic CaCO3, CO2, and C is assessed to address a gap in global budgets. CaCO3 production for the reef framework and inter-reefal deposits is 0.26-0.28 Mt which yields 2.36-2.72 x105 mol yr-1 over the mid- to late-Holocene (<10.5 kyr BP); the period in which the reefs have been active. Holocene CO2 and C production is 0.14-0.16 Mt and 0.06-0.07 Mt, yielding 3.23-3.71 and 5.32-6.12 x105 mol yr-1, respectively. Coral and coralline algae are the dominant sources of Holocene CaCO3 although foraminifers and molluscs are the dominant constituents of inter-reefal deposits. The total amount of Holocene neritic CaCO3 produced by the six submerged coral reefs is several orders of magnitude smaller than that calculated using accepted CaCO3 production values because of very low production, a 'give-up' growth history, and presumed significant dissolution and exports. Total global contribution of submerged reefs to Holocene neritic CaCO3 is estimated to be 0.26-0.62 Gt or 2.55-6.17 x108 mol yr-1, which yields 0.15-0.37 Gt CO2 (3.48-8.42 x108 mol yr-1) and 0.07-0.17 Gt C (5.74-13.99 x108 mol yr-1). Contributions from submerged coral reefs in Australia are estimated to be 0.05 Gt CaCO3 (0.48 x108 mol yr-1), 0.03 Gt CO2 (0.65 x108 mol yr-1), and 0.01 Gt C (1.08 x108 mol yr-1) for an emergent reef area of 47.9 x103 km2. The dilemma remains that the global area and CaCO3 mass of submerged coral reefs are currently unknown. It is inevitable that many more submerged coral reefs will be found. Our findings imply that submerged coral reefs are a small but fundamental source of Holocene neritic CaCO3, CO2, and C that is poorly-quantified for global budgets.

Contents: 1.Exon N, Hill P. Seabed mapping using multibeam swath-mapping systems: an essential technology for mapping Australia's margins. 2.Harris PT, Howard W, O'Brien PE, Sedwick PN, Sikes EL. Quaternary Antarctic ice-sheet fluctuations and Southern Ocean palaeoceanography: natural variability studies at the Antarctic CRC. 3.Colhoun EA. The Late Cainozoic East Antarctic ice sheet. 4.Quilty PG, Truswell EM, O'Brien PE, Taylor F. Paleocene-Eocene biostratigraphy and palaeoenvironment of East Antarctica: new data from the Mac. Robertson Shelf and western parts of Prydz Bay. 5.McCorkle DC, Veeh HH, Heggie DT. Glacial-interglacial palaeoceanography from Australian margin sediments: northwest Australian margin and Great Australian Bight. 6.Heggie DT, Skyring GW, Berelson WM, Longmore AR, Nicholson GJ. Sediment-water interaction in Australian coastal environments: implications for water and sediment quality. 7.Stagg HMJ, Willcox JB, Symonds PA, O'Brien GW, Colwell JB, Hill PJ, Lee CS, Moore AMG, Struckmeyer HIM. Architecture and evolution of the Australian continental margin. 8.Birch GF, Eyre BD, Taylor SE. The use of sediments to assess environmental impact on a large coastal catchment - the Hawkesbury River system. 9.Ferguson A, Eyre B. Behaviour of aluminium and iron in acid runoff from acid sulphate soils in the lower Richmond River catchment. 10.Longmore AR, Heggie DT, Flint R, Cowdell R, Skyring GW. Impact of runoff on nutrient patterns in northern Port Phillip Bay, Victoria. 11.Heggie DT, Skyring GW. Flushing of Australian estuaries, coastal lakes and embayments: an overview with biogeochemical commentary. 12.Perry CJ, Dennison WC. Microbial nutrient cycling in seagrass sediments. 13.Taylor SE, Birch GF. Contaminant dynamics in offchannel embayments of Port Jackson, New South Wales. 14.Heggie DT, Bishop JH, Evans D, Reyes EN, Lee CS. Methane anomalies in seawaters of the Ragay Gulf, Philippines: methane cycling and contributions to atmospheric greenhouse gases. 15.Williamson PE, Forman DJ, le Poidevin S, Summons RE, Stephenson AE. Where is Australia's petroleum and how long will it last? 16.Shaw RD, Korsch RJ, Boreham CJ, Totterdell JM, Lelbach C, Nicoll MG. Evaluation of the undiscovered hydrocarbon resources of the Bowen and Surat Basins, southern Queensland. 17.Wilkins RWT. The problem of inconsistency between thermal maturity indicators used for petroleum exploration in Australian basins. 18.Kennard JM, Allen GP, Kirk RB. Sequence stratigraphy: a review of fundamental concepts and their application to petroleum exploration and development in Australia.

Contents: 1. Lambert IB and Perkin DJ. Australia's mineral resources and their global status. 2. Davidson GJ and Large RR. Proterozoic copper-gold deposits. 3. Dorling SL, Groves DI and Muhling P. Lennard Shelf Mississippi Valley-type (MVT) Pb-Zn deposits, Western Australia. 4. Dowling SE and Hill RET. Komatiite-hosted nickel sulphide deposits, Australia. 5. Gemmell JB, Large RR and Khin Z. Palaeozoic volcanic-hosted massive sulphide deposits. 6. Hoatson DM. Platinum-group element mineralization in Australian Precambrian layered mafic-ultramafic intrusions. 7. Huston DL. The hydrothermal environment. 8. Jaques AL. Kimberlite and lamproite diamond pipes. 9. Kitto PA. Renison-style carbonate-replacement Sn deposits. 10. Lawrie KC and Hinman MC. Cobar-style polymetallic Au-Cu-Ag-Pb-Zn deposits. 11. McGoldrick P and Large RR. Proterozoic stratiform sediment-hosted Zn-Pb-Ag deposits. 12. Mernagh TP, Wyborn LAI and Jagodzinski EA. 'Unconformity related' U and/or Au and/or platinum-group-element deposits. 13. Morris RC. BIF-hosted iron ore deposits - Hamersley style. 14. Phillips GN and Hughes MJ. Victorian gold deposits. 15. Rowins SM, Groves DI and McNaughton NJ. Neoproterozoic Telfer-style Au (Cu) deposits. 16. Senior BR. Weathered-profile-hosted precious opal deposits. 17. Walters SG. Broken Hill-type deposits. 18. Waring CL, Heinrich CA and Wall VJ. Proterozoic metamorphic copper deposits. 19. Wilcock S. Sediment-hosted magnesite deposits. 20. Yeats CJ and Vanderhor F. Archaean lode-gold deposits. 21. Cooke DR and Large RR. Practical uses of chemical modelling - defining new exploration targets in sedimentary basins. 22. Idnurm M and Wyborn LAI. Palaeomagnetism and mineral exploration related studies in Australia: a brief overview of Proterozoic applications. 23. Krassay AA. Outcrop and drill core gamma-ray logging integrated with sequence stratigraphy: examples from Proterozoic sedimentary successions of northern Australia. 24. Waring CL, Andrew AS and Ewers GR. Use of O, C and S stable isotopes in regional mineral exploration. 25. Oliver NHS, Rubenach MJ and Valenta RK. Precambrian metamorphism, fluid flow, and metallogeny of Australia. 26. Taylor G and Butt CRM. The Australian regolith and mineral exploration. 27. Barley ME. Archaean volcanic-hosted massive sulphides. 28. Blevin P. Palaeozoic tin and/or tungsten deposits in eastern Australia. 29. Brand NW, Butt CRM and Elias M. Nickel laterites: classification and features. 30. Butt CRM. Supergene gold deposits. 31. Cooke DR, Heithersay PS, Wolfe R and Calderon AL. Australian and western Pacific porphyry Cu-Au deposits. <strong>Related information</strong> <a href="https://www.ga.gov.au/products/servlet/controller?event=GEOCAT_DETAILS&amp;catno=63681">Blevin PL, Intrusion related gold deposits</a> *Not incuded in original AJGG text. Model first published here September 2005.

Palaeomagnetic polarity sequences have been determined for the lower Yuendumu Sandstone of the Ngalia Basin, and the upper Wonnadinna Dolomite and lower Gnallan-a-gea Arkose of the Georgina Basin to illustrate an application of magnetostratigraphy, i.e. to test previous correlations. The Yuendumu Sandstone of the Ngalia Basin had been correlated with the Arumbera Sandstone because of lithological similarities, as well as palaeogeographic and tectonic considerations. The discovery of trace fossils in the upper Yuendumu Sandstone had supported a correlation with the upper, Cambrian, part of the Arumbera Sandstone. The age of the lower Yuendumu Sandstone was unknown. It was found to be of mixed polarity with a marked normal bias. Magnetostratigraphic comparisons with the polarity pattern from the Amadeus Basin are equivocal: they allow correlations with both the upper part of Arumbera Sandstone I (latest Proterozoic), and the Arumbera Sandstone II-III (Early Cambrian). Since Arumbera II lies unconformably on Arumbera I, we searched for a break within the Yuendumu Sandstone. Photointerpretation and field observation revealed an unconformity within the formation, which, together with the palaeomagnetic data, indicates that the lower part of the sandstone is best correlated with the upper part of Arumbera Sandstone I, and thus is of latest Proterozoic age. The polarity pattern from the Georgina Basin stimulated a reassessment of possible correlations and the collection of new field data. The magnetostratigraphic test was to check whether the reversely magnetised Julie Formation of the Amadeus Basin correlated with the Wonnadinna Dolomite of the Georgina Basin. The magnetostratigraphic result was negative; the Wonnadinna Dolomite is predominantly normally magnetised. This led to an examination of drill cores from near Mount Skinner on the Alcoota 1:250 000 Sheet area, which showed that the Grant Bluff Formation, which elsewhere overlies the Gnallan-a-gea Arkose and the Wonnadinna Dolomite, occurs at depth below correlatives of Arumbera I, the Julie Formation and the upper Pertatataka Formation. It now appears that the Grant Bluff Formation and the Gnallan-a-gea Arkose (Georgina Basin) are correlatives of the Cyclops and Waldo Pedlar Members of the Pertatataka Formation (Amadeus Basin). The Wonnadinna Dolomite is thought to be a correlative of the cap dolomites above the upper tillites of the Ngalia and Amadeus Basins. The new Adelaidean stratigraphy of the central Australian basins has immediate application with regard to Adelaidean Polarity Time Scales; it allows for partial coverage back to the time of the upper glaciation of the late Proterozoic.

The nannostratigraphy of material dredged from the Fremantle Canyon, west of Perth (Western Australia), indicates that the Maastrichtian-Miocene section in the South Perth Basin is more complete than contemporaneous sections in the Perth Abyssal Plain and on the Naturaliste Plateau. The data point to a possible continuous sequence through most of the Paleocene and the entire Eocene in the Fremantle Canyon. In addition to the five rock units previously known to form the Maastrichtian-Miocene succession of the Perth Basin, two (or possibly three) new units have been discovered. The new units, yet to be named, are of Early Eocene and mid Oligocene age; in addition a previously unreported Lower Paleocene sequence could be the lower extension of the Kings Park Formation offshore. The unnamed new Lower Eocene unit fills the stratigraphic gap between the (mainly) Upper Paleocene Kings Park Formation and the Middle Eocene Porpoise Bay Formation. The unnamed new mid (upper Lower) Oligocene unit fits between the Upper Eocene Challenger Formation and the Lower-Middle Miocene Stark Bay Formation, still leaving a large stratigraphic gap between these two formations. The lithological evidence, supported by nannofossil data, indicates that the Porpoise Bay and Challenger Formations merge into a single unit along the canyon walls. This unit is similar to the Lower Eocene and Paleocene carbonates there. A widespread Late Maastrichtian transgression over the Carnarvon and Perth Basins, reaching the Great Australian Bight Basin as an ingression, is seen in the Fremantle Canyon as occurrences of nannofossil association characteristic of the Upper Maastrichtian Breton Marl onshore. Several lines of evidence are discussed to suggest that the onshore Kings Park Formation represents a rapid sea level rise and culmination of the Paleocene transgression over the Perth Basin. Indications of a previously reported significant Middle Eocene reworking episode are recorded at the right level in the Fremantle Canyon succession. Middle Eocene microplanktic components found in the newly reported mid Oligocene of the canyon are thought to have been derived from the Naturaliste Plateau during a major Oligocene erosional event, whose effects have been recorded previously in several DSDP sites in the Southwest Pacific region.

Geoscience Australia contributed a multi-satellite, multi-year weekly time series to the International DORIS Service combined submission for the construction of International Terrestrial Reference Frame 2008 (ITRF2008). This contributing solution was extended to a study of the capability of DORIS to dynamically estimate the variation in the geocentre location. Two solutions, comprising different constraint configurations of tracking network, were undertaken. The respective DORIS satellite orbit solutions (SPOT-2, SPOT-4, SPOT-5 and Envisat) were verified and validated by comparison with those produced at the Goddard Space Flight Center (GSFC), DORIS Analysis Centre, for computational consistency and standards. In addition, in the case of Envisat, the trajectories from the GA determined SLR and DORIS orbits were compared. The results for weekly dynamic geocentre estimates from the two constraint configurations were benchmarked against the geometric geocentre estimates from the IDS-2 combined solution. This established that DORIS is capable of determining the dynamic geocentre variation by estimating the degree one spherical harmonic coefficients of the Earth's gravity potential. It was established that constrained configurations produced similar results for the geocentre location and consequently similar annual amplitudes. For the minimally constrained configuration Greenbelt - Kitab, the mean of the uncertainties of the geocentre location were 2.3, 2.3 and 7.6 mm and RMS of the mean uncertainties were 1.9, 1.2 and 3.5 mm for the X, Y and Z components respectively. For GA_IDS-2_Datum constrained configuration, the mean of the uncertainties of the geocentre location were 1.7, 1.7 and 6.2 mm and RMS of the mean uncertainties were 0.9, 0.7 and 2.9 mm for the X, Y and Z components respectively. The mean of the differences of the two DORIS dynamic geocentre solutions with respect to the IDS-2 combination were 1.6, 4.0 and 5.1 mm with an RMS of the mean 21.2, 14.0 and 31.5 mm for the Greenbelt - Kitab configuration and 4.1, 3.9 and 4.3 mm with an RMS 8.1, 9.0 and 28.6 mm for the GA_IDS-2_Datum constraint configuration. The annual amplitudes for each component were estimated to be 5.3, 10.8 and 11.0 mm for the Greenbelt - Kitab configuration and 5.3, 9.3 and 9.4 mm for the GA_IDS-2_Datum constraint configuration. The two DORIS determined dynamic geocentre solutions were compared to the SLR determined dynamic solution (which was determined from the same process of the GA contribution to the ITRF2008 ILRS combination) gave mean differences of 3.3, -4.7 and 2.5 mm with an RMS of 20.7, 17.5 and 28.0 mm for the X, Y and Z components respectively for the Greenbelt - Kitab configuration and 1.1, -5.4 and 4.4 mm with an RMS of 9.7, 13.3 and 24.9 mm for the GA_IDS-2_Datum configuration. The larger variability is reflected in the respective amplitudes. As a comparison, the annual amplitudes of the SLR determined dynamic geocentre are 0.9, 1.0 and 6.8 mm in the X, Y and Z components. The results from this study indicate that there is potential to achieve precise dynamically determined geocentre from DORIS.

The Mac. Robertson Shelf and western Prydz Bay, on the continental shelf of East Antarctica, were the sites of seismic/coring programs in February- March 1995 and 1997, and of an opportunistic sampling in 1993. Seismic data indicate a prograding sequence, about 200 m thick, dominated by clinoforms, in Palaeogene sediment. Core sampling was accompanied by deployment of a conductivity/temperature/depth probe (CTD), bottom camera and bottom-sediment grab. The Palaeogene sediments overlie Jurassic-Cretaceous sediments or Precambrian basement, and are overlain by thin, olive-green Quaternary diatomaceous ooze and sand. Sampling from the walls and floors of valleys crossing the shelf was on targets defined seismically, and recovered: Weakly lithified black carbonaceous or brown mudstone and siltstone with Paleocene (P4 and Paleocene undifferentiated), Middle Eocene with Globigerinatheka, and other Palaeogene foraminiferid faunas; Paleocene and Eocene pollen, spores and dinoflagellates; Sediments containing a mixture of Palaeogene fossils and Pliocene to Late Pleistocene/ Holocene diatoms and foraminifera; and Evidence of recycling from Permian, Jurassic and Cretaceous sequences. The Palaeogene sediments from the Neilsen Basin and Iceberg Alley contain glauconite and pyrite (the former often, and the latter rarely, pseudomorphic after radiolaria) and, in places, abundant carbonised wood. Radiolaria, teeth and bone fragments are rare. Foraminifera are rare and very dominantly small and calcareous with very few planktonics. The rocks appear to be part of a coastal plain sediment sequence, all weakly lithified, which includes red muddy sandstone and the fossil-bearing lithologies. It is not clear if all the fossil material and enclosing sediments are in situ or have been reworked as fragments into later glacial sediments. The faunas all appear to have accumulated in an inner continental shelf, fully marine environment with temperate-climate water temperature, and where sediment input was high compared with biogenic carbonate production. Several depositional models meet these criteria. Palynology helps define Paleocene and mid-Late Eocene depositional events, the latter marked by the Transantarctic dinocyst flora. The marine Palaeogene can be related to depositional cycles well documented from other parts of the world.

Legacy product - no abstract available

Four benthic marine fossil commumtles are recognised in faunas of the Rhipidomella fortimuscula brachiopod Zone of late Visean (Early Carboniferous) age using multivariate (cluster) analysis of bulk samples extracted from available fossiliferous horizons. As a consequence of their occurrence over a wide geographic area, the communities are considered to be representative collections of in situ invertebrates (largely brachiopods). The number of species and genera in each community varies according to the favourability of water column and substrate conditions for habitation by such invertebrate filter-feeders. Elements of the Balanoconcha elliptica community were present in marine shelf waters with high suspended-sediment concentrations in the water column, such conditions excluded all but a few species well adapted to them. The Rhipidomella fortimuscula community was present in turbulent nearshore conditions, but could also tolerate calmer conditions below wave-base. The Tylothyris planimedia and Marginicintus reticulatus communities inhabited quiet-water conditions, one closer to shore than the other, but differ in the number and variety of species present. The Marginicintus reticulatus community is the most widespread and has the highest species diversity. Sampling by bulk collection allows the communities to be identified by the distribution and abundance of all species. Clusters formed by multivariate analysis identify the recurrent species associations or communities. Examination of the communities show that several species are numerically important in more than one community. It is suggested from this evidence that the communities do not contain mutually exclusive species associations, but are abstractions from a continuum . As such the communities intergrade and are distinguishable on the basis of their total faunal content. Several species comprise the most abundant forms in more than one community: Balanoconcha elliptica, Rhipidomella fortimuscula, Marginicintus reticulatus, and Tylothyris planimedia. The community assemblages are gradational (Whittaker community concept) rather than forming fixed associations inhabiting specific depth zones (Petersen community concept). Compared to the time averaged nature of fossil communities, surveys of modern benthic communities are an instantaneous view of biota and less likely to identify the long-term impact of periodic perturbations. Major periodic fluctuations in environmental parameters are more likely to be reflected over time in the fossil record where the populations of more than one generation are preserved. The inherently patchy nature of both fossil and modern benthic species populations is also a feature readily evident in th e fossil record, but more difficult to detect in modern surveys. Marine benthic communities of the Rhipidomella fortimuscula Zone provide an illustration of the cumulative effects of gradational faunal boundaries and the inherent patchiness of species populations.

New earthquake risk maps of Tasmania have been prepared depicting risk by contours of peak ground velocity, acceleration and intensity with a 10 per cent probability of being exceeded in a 50 year period. The Cornell- McGuire method was used. The maps are based on seismicity up to the end of 1984, including the events of the 1883-1892 earthquake swarm east of Flinders Island and other historical data. The earthquake process was assumed to be Poissonian, so foreshocks and aftershocks were eliminated from the analysis. For this earthquake risk assessment, average eastern Australian background seismicity and attenuation for average site conditions were used. The earthquake source zones most affecting the risk in the Tasmanian region are the West Tasman Sea Zone and the Western Tasmanian Zone. The West Tasman Sea Zone, east of Flinders and Cape Barren Islands, appears to have been the site of the 1883 - 1892 swarm, with at least three intensity-deduced Richter magnitude 6.0- 7.0 events. Consequently, the highest risk land areas are Flinders and Cape Barren Islands, which lie predominantly between the 60 mm.s-1/0.6 m.s-2 and 120 mm.s-1/ 1.2 m.s-2 contours, with the risk increasing to the east. In the Western Tasmanian Zone, the largest event recorded was in 1880. It had an intensity-deduced Richter magnitude of 5.5. The northern part of western Tasmania (enclosed by the 59 mm.s-1/ 0.55 m-2 contour) is the second highest risk region. At Hobart and Launceston, outside the source zones, the values are 23 mm-1 / 0.21 m.s-2 and 30 mm.s-1/ 0.29 m.s-2 respectively, corresponding to a 10 per cent chance of an intensity MMIV - V being exceeded in a 50-year period. However, it appears that site amplification of strong ground motion takes place in some parts of Launceston, and this should be considered when zoning for the Building Code. The chief contributions to uncertainty in the estimates of earthquake risk are uncertainties in early earthquake locations and magnitudes, and in strong ground motion attenuation.