During the Quaternary, the Mac. Robertson shelf of East Antarctica was deeply eroded by glaciers and currents exposing the underlying basement, resulting in a scalped shelf.

The Lower Darling Valley (LDV) Cenozoic sequence contains Paleogene and Neogene shallow marine and shoreline as well as fluvial and shoreline sediments overlain by Quaternary lacustrine, aeolian and fluvial units. Recent investigations in the LDV using multiple datasets have provided new insights into the nature of post-Blanchetown Clay Quaternary fluvial deposition which differs to the Mallee and Riverine Plain regions elsewhere in the Murray Basin. In the LDV Quaternary fluvial sequence, multiple scroll-plain tracts are incised into higher, older and more featureless floodplain terrain. Prior to this study, these were respectively correlated to the Coonambidgal and Shepparton Formations of the Riverine Plain in the eastern Murray Basin. These formations were originally associated with the subsequently discarded Prior Stream/Ancestral River chronosequence of different climatically controlled depositional styles. In contrast to that suggestion, we ascribe all LDV Quaternary fluvial deposition to lateral-migration depositional phases of one style, though with variable stream discharges and channel and meander-scroll dimensions. Successively higher overbank-mud deposition through time obscures scroll traces and provides the main ongoing morphologic difference. A new morphostratigraphic unit, the Menindee Formation, refers to mostly older and higher floodplain sediments, where scroll traces are obscured by overbank mud which continues to be deposited by the highest modern floods. Younger inset scroll-plain tracts, with visible scroll-plain traces, are still referred to as the Coonambidgal Formation. Another new stratigraphic unit, the Willotia beds, refers to even older fluvial sediments, now above modern floodplain levels and mostly covered by aeolian sediments.

Recent centuries provide no precedent for the 2004 Indian Ocean tsunami, either on the coasts it devastated or within its source area. The tsunami claimed nearly all of its victims on shores that had gone 200 years or more without a tsunami disaster. The associated earthquake of magnitude 9.2 defied a Sumatra-Andaman catalogue that contains no nineteenth-century or twentieth-century earthquake larger than magnitude 7.9. The tsunami and the earthquake together resulted from a fault rupture 1,500 km long that expended centuries -worth of plate convergence. Here, using sedimentary evidence for tsunamis, we identify probable precedents for the 2004 tsunami at a grassy beach-ridge plain 125 km north of Phuket. The 2004 tsunami, running 2 km across this plain, coated the ridges and intervening swales with a sheet of sand commonly 5-20 cm thick. The peaty soils of two marshy swales preserve the remains of several earlier sand sheets less than 2,800 years old. If responsible for the youngest of these pre-2004 sand sheets, the most recent full-size predecessor to the 2004 tsunami occurred about 550-700 years ago.

Two facies models are proposed to explain siliciclastic and carbonate depositional systems of 1800 Ma to 1640 Ma age in the Western Fold Belt of the Mt Isa Inlier. Both models record the response of depositional systems to storm-driven processes of sediment transport, dispersal and deposition on a shallow water shelf. The same suite of facies belts can also be identified in sedimentary successions of the Eastern Fold Belt. Slope driven processes of sediment transport and dispersal characterise turbidite and debrite deposits of the Soldiers Cap Group and Kuridala Formation and provide evidence for significantly greater water depths in this part of the basin from ~1685 Ma. Through the recognition of unconformity surfaces, their correlative conformities, maximum flooding and ravinement surfaces the facies belts are packaged into 7 supersequences for the interval 1800-1640 Ma. The new correlations are shown in an Event Chart that correlates linked depositional systems across the entire Mt Isa Inlier. Thick successions of turbidite and debrite deposits are restricted to the eastern parts of the Mt Isa Inlier and do not occur in the Western Fold Belt. A major phase of extension and rifting commenced at ~1740 Ma and by ~1690 Ma led to significant crustal thinning and increased rates of accommodation over an area east of the Selwyn Fault and Burke River Structural Belt. In the Mitakoodi and Selwyn Blocks the rapid transition from shallow water shelf depositional systems of the Prize Supersequence to significantly deeper water slope environments of the Gun Supersequence coincided with the development of a platform margin, the deposition of turbidite and debrite deposits in deep water on the continental slope and the intrusion of mafic sills and dykes. Turbidite and debrite depositional systems of the Soldiers Cap Group and Kuridala Formations are restricted to a lowstand wedge of siliciclastic facies deposited basinward of a platform margin. Basin geometries and sediment architectures associated with this extensional event and recorded in the Gun Supersequence (~1685 Ma to 1650 Ma) provide an explanation for the geographic separation and fluid evolution pathways responsible for the Mt Isa Type and Broken Hill Type Zn-Pb-Ag deposits.

Recently discovered drift deposits on the Antarctic continental shelf provide access to information on the Holocene palaeoceanography of the bottom current regime within deep shelf basins that were previously inaccessible. The George Vth Basin on the East Antarctic margin has been identified by oceanographers as an important source of Antarctic Bottom Water, hence the Holocene history of bottom current activity here may be relevant to variations in bottom water export.

The Fitzroy catchment is the largest Queensland catchment discharging to the Great Barrier Reef (GBR) lagoon. Sediments and nutrients together with anthropogenic pollutants originating upstream in the catchment are discharged from the Fitzroy River via the Fitzroy Estuary (FE) and ultimately into Keppel Bay (KB). The estuary and the bay act as natural chemical reactors where the materials delivered undergo chemical and physical transformations before some are deposited and stored in the growing deltaic and beach areas, with the remainder transported eastward to the southern zone of the GBR lagoon.

In this study of the beach-ridge plain at Keppel Bay, on the central coast of Queensland, we examine ridge morphology, sediment texture and geochemistry. We build a detailed chronology for the ridge succession using the optically stimulated luminescence (OSL) dating method. Although our interpretations are preliminary, our results suggest that significant changes have occurred in the rate of shoreline accumulation of sediment, catchment sediment source areas, and that there have been minor falls in relative sea level.

The release of fluid to the seabed from deeper sources is a process that can influence seabed geomorphology and associated habitats, with pockmarks a common indicator. In May 2012, Geoscience Australia led a multidisciplinary marine survey in Joseph Bonaparte Gulf, to facilitate an assessment of the potential for fluid leakage associated with geological storage of CO2 at depth within the Petrel Sub-basin. Multibeam bathymetry and backscatter mapping (652 km2), combined with acoustic sub-bottom profiling (655 line-km) and geomorphological and sediment characterisation of the seabed was undertaken. Seabed geomorphic environments identified from 2 m resolution bathymetry include carbonate banks and ridges, palaeochannels, pockmark fields and fields of low amplitude hummocks. This paper focuses on pockmarks as indicators of fluid seepage from the subsurface. Three principal pockmark morphologies (Type I, II and III) are present with their distribution non-random. Small unit (Type I) depressions occur on plains and in palaeochannels, but are most commonly within larger (Type II) composite pockmarks on plains. Type III pockmarks, intermediate in scale, are only present in palaeochannels. The timing of pockmark formation is constrained by radiocarbon dating to 14.5 cal ka BP, or later, when a rapid rise in sea-level would have flooded much of outer Joseph Bonaparte Gulf. Our data suggest the principal source of fluids to the seabed is from the breakdown of organic material deposited during the last glacial maxima lowstand of sea-level, and presently trapped beneath marine sediments. These results assist in ameliorating uncertainties associated with potential CO2 storage in this region.

Zircons within the Eocence Garford Paleochannel, central South Australia, were derived from two main sources: (1) local Archean-Mesoproterozoic rocks of the Gawler Craton exposed within the paleocatchment, including the 2525-2440 Ma Mulgathing Complex and 1595-1575 Ma Gawler Range Volcanics-Hiltaba Suite, and (2) Phanerozoic sedimentary rocks within the catchment that contribute a late Mesoproterozoic to Cretaceous component of recycled zircons from a variety of primary sources. These sources include the 1190-1120 Ma Pitjantjatjara Supersuite and 1080-1040 Ma Giles Complex, within the Musgrave Province; c. 510 Ma syn-Delamerian magmatism possibly derived from the Adelaide Rift Complex; and Jurassic-Cretaceous zircons ranging from ~220 Ma to ~100 Ma, with one statistical population at 122 ± 3 Ma. It is likely that zircons from these sources outside the paleocatchment were transported into the Mesozoic rocks of the Eromanga Basin within the catchments, before being re-eroded into the Garford Paleochannel. Given the presence of significant gold mineralization within the Neoarchean rocks of the Gawler Craton, the abundance of locally-derived Archean zircons may support the potential for paleoplacer gold deposits within the Eocene paleodrainage system. Likewise, the abundance of zircons derived from the Gawler Range Volcanics/Hiltaba Suite may support the notion that potential secondary uranium mineralisation within the paleochannels may have a source in these commonly uranium-enriched Mesoproterozoic volcanics and granites. Finally, these data suggest that the Garford Paleochannel was not a major contributor to the zircon budget of the paleo-beach heavy mineral sands province of the adjacent Eucla Basin.

A growing need to manage marine biodiversity sustainably at local, regional and global scales cannot be met by applying the limited existing biological data. Abiotic surrogates of biodiversity are thus increasingly valuable in filling the gaps in our knowledge of biodiversity patterns, especially identification of hotspots, habitats needed by endangered or commercially valuable species and systems or processes important to the sustained provision of ecosystem services. This review examines the use of abiotic variables as surrogates for patterns in benthic assemblages with particular regard to how variables are tied to processes affecting biodiversity and how easily those variables can be measured at scales relevant to resource management decisions.