We undertook a biological data acquisition program as part of the transit of the R.V. Southern Surveyor between Darwin and Cairns 15-24 October 2012. The overarching aim of this program was to use an ROV and benthic sled to collect benthic marine information and specimens for biodiversity and biodiscovery research in areas previously mapped by Geoscience Australia during survey GA-276, including a bank (Area I) and terrace/hole feature within the proposed Wessel Islands CMR (Area II). This study focuses on sessile invertebrates such as sponges and octocorals due to their ecological importance as habitat providers and their chemical importance as sources of marine natural products and medicines. In less than 24 hours of sampling effort, survey SS2012/t07 resulted in 261 voucher specimens which will be used for biodiversity and natural products research. A total of 49 samples are to be lodged at the ABL, and samples with weights larger than 300 g will be sent to the NCI for screening of active compounds against cancer and HIV. Sponges were the most abundant group collected based on both biomass (~ 139 kg) and number of voucher specimens (93), followed by cnidarians (30 kg, 73 vouchers), particularly hard corals (23 kg, 11 vouchers). As expected the top of the bank in Area I had a seemingly diverse and abundant sessile invertebrate community, with consistent patchy occurrence of sponges, octocorals, and hard corals. The terrace at in Area II supports moderate densities of sponges and octocorals, while the adjacent deep hole at ~ 100 m seems to be covered with muddy gravel and supports scattered mobile and sedentary invertebrates, of which crinoids dominate, as well as skates and numerous small demersal fish.

The formation of incised valleys on continental shelves is generally attributed to fluvial erosion under low sea level conditions. However, there are exceptions. A multibeam sonar survey at the northern end of Australia's Great Barrier Reef, adjacent to the southern edge of the Gulf of Papua, mapped a shelf valley system up to 220 m deep that extends for more than 90 km across the continental shelf. Based on observations, we propose a new conceptual model for the formation of tidally incised shelf valleys.

Lord Howe Island is a volcanic island, rising to over 800 m, draped with Late Quaternary submarine and subaerial carbonate sediments. The island and neighbouring islets lie within a chain of seamounts and is presently at or close to the latitudinal limit to coral reef growth. Lord Howe Island and adjacent Balls Pyramid, composed of the basalts erupted around 6 million years ago, sit near the middle of broad shelves on separate peaks of one major volcanic edifice. The central part of the Lord Howe Island is covered by calcarenite that was deposited primarily as dunes (eolianite), but with isolated beach units. Uranium-series, amino acid racemisation, and thermoluminescence dating indicate that many of these were deposited during marine oxygen isotope stage 5. Eolianite units stratigraphically below the beach deposits are of penultimate interglacial, or in places perhaps older, age. Different suites of erosional landforms are associated with different lithologies. Towering plunging cliffs characterise the resistant Mount Lidgbird Basalt, in some cases fringed with large talus slopes. On less resistant lithologies or where nearshore topography means greater wave force as a result of waves breaking, there are shore platforms. Slumping cliffs abut broad erosional platforms on the poorly lithified calcarenite. A fringing reef on the western side of Lord Howe Island, the southernmost coral reef in the Pacific, is dominated by coral and coralline algae.Carbonate sediments veneering the shelf around the islands contain a more temperate biota. Located at the southern limit of reef-forming seas, but apparently having undergone erosion for much of its history outside of reef seas, Lord Howe Island provides insights into marine planation of volcanic islands close to what has been termed the Darwin Point. It represents the initial stages of fringing reef development on a volcanic island.

A document briefly describing levelled ship-track gravity and magnetic data available for download from the Geophysical Archive Data Delivery System (GADDS) that cover the southwest margin of Australia in the region enclosing 106-120°E and 19-37°S. The document will be provided whenever the data are downloaded from GADDS. Note that the data is archived on the Corporate Data Store

Legacy product - no abstract available

Legacy product - no abstract available

Legacy product - no abstract available

Seismic acquisition for the joint BMR-Woodside Petroleum program in the Dampier Sub-basin started at 0800 am on October 24, 1990 and was completed at 1150 am on Sunday October 28, 1990. A total of 352 km of high resolution seismic data was collected along the 17 agreed survey lines, of which 336 km were full stack data with a total 390 magnetic tapes being used. Data quality appears to be good. In addition to the seismic, a total of 530.6 km of water column geochemical data were also collected.

The southern margin of Australia has long been considered an example of a classic passive rifted continental margin. In recent times, it has been cited as an example of a 'lower plate' margin in the terminology describing detachment models of passive margin formation.However, despite extensive study by both industry and government since the early 1970s, some fundamental aspects of the structure and geological history of the margin remain speculative. It is proposed here to use the AGS0 research vessel Rig Seismic to acquire 4087 km of deep-seismic data (16 s record length) in the central Great Australian Bight (GAB) and across the continental margin south of Western Australia. The survey has three principal objectives: 1. To enhance understanding of the tectonic evolution / event history of the southern margin in support of DPIE' s Acreage Release Program and thus to encourage successfulpetroleum exploration. 2. To provide the necessary framework data in support of a proposal submitted to the Ocean Drilling Program (ODP) for drilling in the GAB; and 3. To provide data in the GAB that support Australia's claim to a Legal Continental Shelf beyond the 200 n.m. Exclusive Economic Zone (EEZ) as defmed under the 1982 UNConvention on the Law of the Sea (UNCLOS). The specific scientific aims of the work include: - Definition of the deep crustal structure of the region and the mode of margin formationacross a number of key transects. In particular, to image the key detachment surfaces which are believed to have controlled the extensional processes. Interpretation of the deepstructures will be enhanced by seismic refraction data recorded by Lamont-Doherty Geological Observatory in 1976 (Talwani et al., 1979). - Determination of the location and structural setting of the continent-ocean boundary. In places, stratified tilt-blocks that lie oceanwards of the magnetically determined COBsuggest that either the COB identification is incorrect, old oceanic crust has been re-rifted, or the seismic data are imaging an amalgam of oceanic crust and continental slivers. - Determination of the structure and origin of the enigmatic Diamantina Zone, west of the GAB, and its relationship, if any, to the change in seafloor spreading rate at 44 Ma. Is the crust to the north oceanic, or is it highly extended continental?

This record is a summary of the preliminary results of the second AGSO/Antarctic Co-operative Research Centre/ANARE marine geoscience program in Prydz Bay, the Mac.Robertson Shelf, Antarctica and the Kerguelen Plateau (Fig.1). The cruise program consisted of activities aimed at understanding modern sedimentary processes on the Antarctic margin, understanding the Plio-Pleistocene environmental history of the region and obtaining samples from the Kerguelen Plateau to illuminate the history of water mass reorganisation in the Southern Ocean during Quaternary climate change episodes. The cruise is designated AGSO survey 149 in AGSO's data bases and has the acronym BANGSS (Big ANtarctic Geology and Seismic Survey) in Antarctic Division data sets. The cruise program set out in O'Brien et al., (1995) was to meet the common goal of the Antarctic CRC Natural Variability (sediments) sub-program and the ASAC strategic plan for Antarctic Geosciences which is to promote a better understanding of global climate change by providing statements of the Antarctic and Southern Ocean palaeoenvironments over the following time intervals: (A)0-10,000 years (post-glacial warming) (B)0-160,000 years (last glacial cycle) (C) 0-5,000,000 years (Pliocene "warming" of Antarctica). Studies of modern sediment transport and modern organisms that contribute to Quaternary sediments were designed to aid the understanding of the ancient sedimentary record and the modern Antarctic environment. Seismic lines and sampling on this cruise were also expected to provide insights into the tectonic and stratigraphic development of the parts of the Antarctic margin. The three features targeted for study during the cruise were: (A) the trough-mouth fan deposits adjacent to Prydz Bay; (B) sediment traps associated with deep, shelf-basins on the Mac.Robertson Shelf; and (C) sediments on the Kerguelen Plateau. These features were selected because in anticipation that they should provide insights into Antarctic environmental history. Sediments deposited in Prydz Bay should contain a record of ice sheet fluctuations because of their location at the downstream end of the largest outlet glacier draining from the East Antarctic Ice Sheet, the Lambert Glacier. The Mac.Robertson Shelf, in contrast, was glaciated by ice originating entirely in the adjoining coastal region. It also contains deep basins that contain thick Holocene sediments that are useful in the detailed study of post-glacial environmental change. The Southern Ocean is a major component of the global climate system. Its water masses play a pivotal role by absorbing, transporting and releasing heat and by transferring oxygen, nutrients and CO2 to and from the deep ocean. In this context, the Kerguelen Plateau has accumulated sedimentary sequences that will contain records of how the Polar Front and its associated water masses have varied between glacial and interglacial periods.