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This paper presents tectonic elements maps for the continental margin of East Antarctica, from 38-164E, together with brief descriptions of all the major tectonic elements.

Despite long history of studies the Wallaby Plateau offshore Western Australia remains a controversial feature. Analysis of interval seismic velocities from Geoscience Australia's 2008/09 seismic survey 310 in conjunction with seismic reflection interpretation provides new insights into the geology of the Plateau. Seismically distinctive divergent dipping reflector sequences (DDRS) have been identified. The seismic character of the DDRS is similar to seaward dipping reflector sequences (SDRS) of inferred volcanic composition. Initial analysis of seismic velocity profiles indicated affinities between the DDRS packages and known sedimentary strata in the Houtman Sub-basin. Effect of water loading on seismic velocities is commonly ignored in offshore studies. However, direct comparative analysis of interval velocity patterns between areas of significantly different water depth requires various water pressure related changes in velocity to be accounted for. There are controversies in methodology and application of water depth adjustment to seismic velocities, and presentation of velocity models as function of pressure rather than two-way time, or depth emerges as a possible solution. Water depth adjustment of seismic velocities analysed in our study reduces distinction between SDRS, DDRS and sedimentary strata such that discrimination between volcanic and sedimentary strata in DDRS or SDRS is equivocal. A major uncertainty of this interpretation is due to a lack of the reference velocity model of SDRS and DDRS investigated globally.

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