The Petrel Sub-basin Marine Environmental Survey GA-0335, (SOL5463) was undertaken by the RV Solander during May 2012 as part of the Commonwealth Government's National Low Emission Coal Initiative (NLECI). The survey was undertaken as a collaboration between the Australian Institute of Marine Science (AIMS) and GA. The purpose was to acquire geophysical and biophysical data on shallow (less then 100m water depth) seabed environments within two targeted areas in the Petrel Sub-basin to support investigation for CO2 storage potential in these areas. This dataset comprises an interpreted geomorphic map. Interpreted local-scale geomorphic maps were produced for each survey area in the Petrel Sub-basin using multibeam bathymetry and backscatter grids at 2 m resolution and bathymetric derivatives (e.g. slope; 1-m contours). Five geomorphic units; bank, plain, ridge, terrace and valley, were identified and mapped using definitions suitable for interpretation at the local scale (nominally 1:10 000). Maps and polygons were manual digitised in ArcGIS using the spatial analyst and 3D analyst toolboxes.

Probabilistic seismic hazard analyses in Australia rely fundamentally on the assumption that earthquakes recorded in the past are indicative of where earthquakes will occur in the future. No attempt has yet been made to assess the potential contribution that data from active fault sources might make to the modelling process, despite successful incorporation of such data into United States and New Zealand hazard maps in recent years. In this paper we review the limited history of paleoseismological investigation in Australia and discuss the potential contribution of active fault source data towards improving our understanding of intraplate seismicity. The availability and suitability of Australian active fault source data for incorporation into future probabilistic hazard models is assessed, and appropriate methodologies for achieving this proposed.

This cross agency report, highlights the areas of the central NSW continental slope prone to sediment mass wasting over time. It includes the critical factors which contribute to slope failure including basement geometry, angle of slope and thickness of overlying sediments. Evidence of slope failure are observed through: surficial tension cracks; creep features; faulting; redistribution of sediments, multiple relict slides on the sea floor and erosional surface scars.

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The role of neotectonism in the recent landscape evolution of the Eastern Blue Mountains, NSW Dan Clark, Andrew McPherson and Kerrie Tomkins Faults of the Lapstone Structural Complex (LSC) underlie 100 km, and perhaps as much as 160 km, of the eastern range front of the Blue Mountains, west of Sydney. More than a dozen major faults and monoclinal flexures have been mapped along its extent. The Lapstone Monocline is the most prominent of the flexures, and accounts for more than three quarters of the deformation across the complex at its northern end. Opinion varies as to whether recent tectonism, erosional exhumation of a pre-existing structure, or a combination of both, best accounts for the deeply dissected Blue Mountains plateau that we see today. We present results from an ongoing investigation of Mountain Lagoon, a small fault-bound basin bordering the Kurrajong Fault in the northern part of the LSC. Drilling has identified 15 m of fluvial, colluvial and lacustrine sediments overlying shale bedrock trapped behind a sandstone fault barrier corresponding to the Kurrajong Fault. Dating of pollen grains preserved in the basal sediments overlying shale suggest that the fault angle depression began trapping sediment in the Early to Middle Miocene. Strongly heated Permo-Triassic gymnosperm pollen in the same strata provides circumstantial evidence that sediment accumulation postdates the emplacement of basalts at Green Scrub at ca. 18.8 Ma. Our results indicate that only 15 m of the 130 m of throw across the Kurrajong Fault is Neogene in age. From this it may be deduced that erosional exhumation is the dominant process responsible for formation of the deeply dissected Blue Mountains landscape. However, it is also possible to demonstrate the influence of ongoing tectonism on stream channel over-steepening, knick point initiation, and the continuing dissection of the plateau.

For the purpose of obtaining a general understanding of the geology of North Stradbroke Island, field work was carried out on the island from January 8th to February 17th, 1948. Altimeter traverses were made from Dunwich, Amity, Point Lookout and Blue Lake, and from the connecting roads. The southern portion was covered from landing points on the west coast near Russel Island. The results of observations were plotted on to Military Map Queensland Zone 8, No. 182 (Brisbane Valley). Altimeter readings were corrected from the readings of a weekly barograph stationed at Dunwich, on the western side of the island. This report is comprised in two parts. In Part I, the physiography and the geology of the island are described. In Part II, an account is given of the history of the development of the island.

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.

A geological investigation was carried out by the writer. The aim was to check the previous mapping of the geology, and if necessary, to assist the Magnetician in locating a suitable site for magnetic observations. Some aspects of geomorphology, and the reconnaissance survey work carried out are discussed in this report.

During the summer of 1947, an expedition was despatched to Heard Island with the object of landing a party to spend about twelve months there. Geological work was undertaken by the writer. The results of this work are recorded in this report. These results include observations on the geomorphology of the island, and a description of the xenolithic ejectamenta collected from the tuffs of Rogers Head and Rogers Head Peninsula.

Measurements of water turbidity, currents, seafloor sediment samples and geophysical data document the sedimentary processes and the Late Quaternary sedimentary history of a continental shelf valley system on the East Antarctic continental margin.