The combined analysis of airborne electromagnetics (AEM), airborne gamma-ray spectrometry (AGRS), magnetics and a digital elevation model with ground-based calibration, has enable construction of a 3D architectural and landscape evolution model of valley fill deposits around the township of Jamestown in South Australia. The valley fill sediments consist of traction, suspension and debris-flow deposits that range in age (optically stimulated luminescence OSL dating) from 102 ka (±12) to the present day. A sediment isopach map generated from the AEM dataset reveals the 3D structure of the valley-fill deposits. The sediments are up to 40 m thick within asymmetrical valleys and are the result of colluvial fan, floodplain and sheet-wash processes. The sediments fine upwards with a higher proportion of coarser bed load deposits toward the base and fine sand, silt and clay towards the top of the sequence. A strong linear correlation between airborne K response and soil texture allowed the percentage of surface silt to be modelled over the depositional landforms. The sediments are thought to have been derived by a combination of aeolian dust accessions, and weathering and erosion of bedrock materials within the catchment. Older drainage lines reflected in the distribution of relatively closely spaced and well connected 'magnetic channels' differ markedly from present day streams that are largely ephemeral and interrupted. This is thought to reflect a change in local hydrology and associated geomorphic processes from relatively high to lower energy conditions as the valley alluviated. These hydrological changes are likely to be associated with a drying climate, lower recharge and runoff.

In 1946 and 1947 the writer had excellent opportunities to study the effect of lateritisation in the course of geological reconnaissances in Northern Australia. From field evidence which has been collected on several aspects of lateritisation - origin, products and relationship to geomorphological processes - a detailed account of lateritisation in Australia can be given. Lateritisation and the occurrence of opal are discussed in this report.

Lithostratigraphy, grain sizes and down-hole logs of Site 1166 on the continental shelf, and Site 1167 on the upper slope, are analyzed to reconstruct glacial processes in eastern Prydz Bay and the development of the Prydz trough-mouth fan. In eastern Prydz Bay upper Pliocene-lower Pleistocene glaciomarine sediments occur interbedded with open-marine muds and grade upward into waterlaid tills and subglacial tills. Lower Pleistocene sediments of the trough-mouth fan consist of coarse-grained debrites interbedded with bottom-current deposits and hemipelagic muds, indicating repeated advances and retreats of the Lambert Glacier-Amery Ice Shelf system with respect to the shelf break. Systematic fluctuations in lithofacies and down-hole logs characterize the upper Pliocene-lower Pleistocene transition at Sites 1166 and 1167 and indicate that an ice stream advanced and retreated within the Prydz Channel until the mid Pleistocene. The record from Site 1167 shows that the grounding line of the Lambert Glacier did not extend to the shelf break after 0.78 Ma. Published ice-rafted debris records in the Southern Ocean show peak abundances in the Pliocene and the early Pleistocene, suggesting a link between the nature of the glacial drainage system as recorded by the trough-mouth fans and increased delivery of ice-rafted debris to the Southern Ocean.

In order to protect the biological diversity of marine life in Australia's Exclusive Economic Zone (EEZ), the commonwealth government has passed the Environmental Protection and Biodiversity Conservation (EPBC) Act. The Act is being implemented through preparation of regional marine plans (commenced in 2001) and by designing networks of representative marine protected areas (MPAs) in both commonwealth and state waters. In the absence of direct information about the distribution of seabed biodiversity, appropriate surrogates must be used instead. A major constraint is the short time-frame available to managers to make decisions; only information that is readily accessible and available can be used under these circumstances. Existing seabed bathymetry data were used to produce a geomorphic features map of the Australian EEZ. This map was used in conjunction with existing fish diversity information and other data to derive a Benthic Bioregionalisation (2005) that subdivides Australia's EEZ into 41 bioregions including 24 biologically unique provinces. Biophysical variables measured at broad spatial scales apart from bathymetry (and derived variables such as seabed slope) include ocean primary production, seabed sediment properties, temperature and sediment mobilisation due to waves and tides. To better characterise habitats on the Australian continental margin, Geoscience Australia has created 'seascape' maps that integrate multiple layers of spatial data that are useful for the prediction of the distribution of biodiversity. Existing seabed bathymetry data were used to produce a geomorphic features map of the Australian EEZ. This map was used in conjunction with existing fish diversity information and other data to derive a Benthic Bioregionalisation (2005) that subdivides Australia's EEZ into 41 bioregions including 24 biologically unique provinces.

The Australian continent is actively deforming in response to far-field stresses generated by plate boundary interactions and buoyancy forces associated with mantle dynamics. On the largest scale (several 103 km), the submergence of the northern continental shelf is driven by dynamic topography caused by mantle downwelling along the Indo-Pacific subduction system and accentuated by a regionally elevated geoid. The emergence of the southern shelf is attributed to the progressive movement of Australia away from a dynamic topography low. On the intermediate scale (several 102 km), low-amplitude (c. 100–200 m) long-wavelength (c. 100–300 km) topographic undulations are driven by (1) anomalous, smaller-scale upper mantle convection, and/or (2) lithospheric-scale buckling associated with plate boundary tectonic forcing. On the smallest scale (101 km), fault-related deformation driven by partitioning of far-field stresses has modified surface topography at rates of up to c. 170 m Ma-1, generated more than 30–50% of the contemporary topographic relief between some of Australia’s highlands and adjacent piedmonts, and exerted a first-order control on long-term (104–106 a) bedrock erosion. Although Australia is often regarded as tectonically and geomorphologically quiescent, Neogene to Recent tectonically induced landscape evolution has occurred across the continent, with geomorphological expressions ranging from mild to dramatic.

Controls on the evolution of Tapora Island, an active barrier island located opposite the entrance to the Kaipara Harbour on the high-energy west coast of the North Island of New Zealand are identified. Subsurface facies form an aggradational barrier island succession from subtidal to subaerial elevations. These data, combined with surface samples and geomorphic and geologic relationships, indicate that Tapora Island is the most recent barrier island at this location in the estuary, and forms part of a prograded coast opposite the entrance. Wave data indicate that ocean swell waves penetrate the inlet for approximately two hours either side of high tide and are capable of transporting sand onto the island. The combined effects of swell waves, abundant sediment supply, and exposed aspect are the critical factors that have formed the barrier island. Despite the 'sheltered' estuarine setting, Tapora Island has formed under conditions that are more akin to open ocean coasts. The origin and development of Tapora Island broadly conforms to the accumulating barrier island model.

The overarching theme of this book (and for the GeoHab organisation in general) is that mapping seafloor geomorphic features is useful for understanding benthic habitats. Many of the case studies in this volume demonstrate that geomorphic feature type is a powerful surrogate for associated benthic communities. Here we provide a brief overview of the major geomorphic features that are described in the detailed case studies (which follow in Part II of this book). Starting from the coast we will consider sandy temperate coasts, rocky temperate coasts, estuaries and fjords, barrier islands and glaciated coasts. Moving offshore onto the continental shelf we will consider sandbanks, sandwaves, rocky ridges, shallow banks, coral reefs, shelf valleys and other shelf habitats. Finally, on the continental slope and deep ocean environments we will review the general geomorphology and associated habitats of escarpments, submarine canyons, seamounts, plateaus and deep sea vent communities.

This report describes the field survey carried out in Cockburn Sound, Western Australia by Geoscience Australia (GA) staff for the Coastal Geomorphology and Classification Subproject (CG) of the Coastal Water Habitat Mapping Project (CWHM). It documents the various sampling techniques and procedures used to collect surface and subsurface samples from the Sound; details of the vibracores and grab samples recovered and the proposed analyses to be performed on these samples. The results of the analysis of the grab samples will be used to classify the various surface sediment types encountered as well as map their distribution within Cockburn Sound. The analysis and interpretation of the vibracores will allow the reconstruction of the stratigraphic framework of Cockburn Sound. This information will be used in conjunction with the findings of the other subprojects in the CWHM Project. For example, it will assist in ground-truthing the results of the both the single and multi-beam sonar surveys that have and are to be carried out within Cockburn Sound by Curtin University. It will also provide key substrate information for incorporation into a more comprehensive benthic habitat classification for the sound.

Presentation to be delivered at the Western Australian Marine Science Institution Symposium, Fremantle, 21 February Abstract text: Geoscience Australia, as the Australian Government's geoscience agency, has a long history of marine environment mapping and research on the North West Shelf of Australia. In recent times, several data acquisition surveys have been completed and subsequent interpretive products have been produced under Commonwealth Government programmes, including: the Offshore Energy Security Program (2006-2011); the Marine Biodiversity Hub under the Commonwealth Environmental Research Facilities (CERF) and the National Environmental Research Program (NERP), and; the National CO2 Infrastructure Plan (NCIP, 2011-15). Collaborations, such as those facilitated by CERF and NERP, and with the Australian Institute of Marine Science (AIMS), have resulted in further work in the region. Areas of investigation have included the North Perth Basin, Bonaparte Gulf and Timor Sea. Using data from these surveys and other sources, GA is continuing to develop regional-scale seabed datasets, including bathymetry, geomorphology, sediment properties, seabed disturbance and seabed hardness that are publicly available via the internet. A pilot program was started in 2010 to collate and archive environmental data generated by the offshore petroleum industry, with a focus on the North West Shelf. Geoscience Australia is currently undertaking marine surveys to provide seabed environmental information to support assessments of the CO2 storage potential of several offshore sedimentary basins under NCIP. A marine survey over the Browse Basin in May 2013, to be undertaken in collaboration with the AIMS, will acquire high-resolution bathymetry and information on seabed and shallow subsurface geology and ecology. Follow-up surveys are also proposed during 2013-2015. The Browse survey results will be publicly released as a data package integrating existing and the newly acquired seabed data, and in a report to the Department of Resources Energy and Tourism on the CO2 storage potential of selected areas of the Browse Basin.

Northern Australia has been the focus of recent marine biodiversity research to support natural resource management for both industry and conservation, including management of the Oceanic Shoals Australian Marine Park (AMP). Much of this research has targeted habitat-forming sessile invertebrates and charismatic megafauna, but smaller macrofauna and infauna may also be important because of their roles in ecosystem functions. In this study we characterised the biodiversity of polychaetes collected from four marine surveys to the Oceanic Shoals AMP between 2009 and 2012 from which sediment samples were elutriated (500 μm) to separate macrofauna. We used this species-level inventory to examine several questions related to marine management, namely: (1) do polychaete assemblages vary among surveys; (2) can environmental variables or geomorphology explain differences in community structure; and (3) how do ecological patterns change according to taxonomic resolution (species, family) and functional group (feeding, habitat, mobility)? A total of 2561 individual polychaetes were collected from 266 samples, representing 368 species and 43 families, including new species and genera, as well as new family records for Australia (Iospilidae, Lacydoniidae). Polychaete species assemblages and functional groups showed variation among the surveys, but this was not observed at the family level. Species and family assemblages were weakly related to environmental factors, but functional groups showed stronger relationships. Plains and banks each supported distinct polychaete assemblages, although the latter showed temporal variation. The results provide baseline biodiversity and ecological data about polychaetes on the northern Australian shelf, and these are discussed in relation to marine management strategies. Notably, intersurvey and environmental patterns differ from those of larger sessile fauna (sponges) collected on the same surveys, highlighting the need to consider small macrofauna in monitoring programs of marine protected areas. <b>Citation:</b> Przeslawski Rachel, Glasby Christopher J., Nichol Scott (2019) Polychaetes (Annelida) of the Oceanic Shoals region, northern Australia: considering small macrofauna in marine management. <i>Marine and Freshwater Research</i> 70, 307-321. https://doi.org/10.1071/MF18060