The AGSO Cities Project was established in 1996 to undertake research directed towards the mitigation of the risks faced by Australian urban communities that are posed by a range of geohazards. Geohazards are broadly defined to include all earth surface processes with the potential to cause loss or harm to the community or the environment. The ultimate objective is to improve the safety of communities, and consequently make them more sustainable and prosperous. To provide a realistic focus to this research, and to achieve practical outcomes, the Cities Project is using a series of case studies based on Queensland centres to develop and test its science and techniques. Cairns is the first of these multi-hazard case studies. Cairns is the most northerly of Queensland's cities and one of the fastest growing communities in Australia. It is also an isolated community, located some 1 400 km from Brisbane (Figure (i)). Cairns has a resident population of approximately 120 000 and this total can exceed 150 000 at the height of the tourist season.

The Australian Geological Survey Organistaion (AGSO) has produced a set of digital bathymetry, gravity and magnetic grids for the southwest quadrant of Australia (24 - 46S, 106-140E), using all available land, marine and satellite data. The work was done in cooperation with Desmond Fitzgerald & Associates (DFA), and with significant bathymetric data input from the Australian Hydrographic Office (AHO). The results were obtained by performing a network adjustment on marine ship-track data, and combining these with onshore and satellite-derived data.

Several grounding zone wedges were left on the floor and flanks of Prydz Channel in western Prydz Bay by the Lambert Glacier during the last glacial cycle. Seismic profiles indicate that vertical accretion at the glacier bed was the most important depositional process in forming the wedges, rather than progradation by sediment gravity flows. Sidescan sonographs reveal extensive development of flutes on the sea floor inshore from the wedges, indicating deformable bed conditions beneath the ice. The region inshore of the east Prydz Channel wedge features extensive dune fields formed by currents flowing towards the grounding zone. This orientation is consistent with models of circulation beneath ice shelves in which melting at the grounding line generates plumes of fresher water that rise along the base of the ice shelf, entraining sea water into a circulation cell. The Lambert Deep is surrounded by a large composite ridge of glacial sediments. Internal reflectors suggest formation mostly by subglacial accretion. The sea floor in the Lambert Deep lacks dune fields and shows evidence of interspersed subglacial cavities and grounded ice beneath the glacier. The absence of bedforms reflects sea floor topography that would have inhibited the formation of energetic melt water-driven circulation.

A petrophysical dataset for the Broken Hill region, NSW.

No abstract available

Abstracts from conference

Terracorp was contracted by ANSIR of Canberra to conduct the 1999 Cabgas Seismic survey located in the Darling Basin. In total 160.02 of 120 fold, 240 channel data was recorded between 1st February and 18 February1999. This report covers various field operations relating to experimentals, line clearing, chaining, surveys, recording and field processing.

Terracorp under its facilities management agreement with ANSIR was contracted to conduct the 1999 Yilgarn Seismic Survey located in the Kalgoorlie Goldfields region of Western Australia. In total 194.64 kms of 60 and 120 fold, 240 channel data was recorded between 19th August and 3rd September 1999. This report covers various field operations relating to experimentals, line clearing, chaining, surveys, recording and field processing. The contract was supervised by Mr Andrew Owen of ANSIR.

Terracorp under its facilities management agreement with ANSIR was contracted to conduct the 1999 Lachlan and Marsden Seismic Surveys located around West Wyalong, NSW. In total 206.47 kms of 60, 80 and 120 fold, 160 & 240 channel data was recorded between 11th September 1999 and 29th September 1999. This report covers various field operations relating to experimentals, line clearing, chaining, surveys, recording and field processing. Mr David Johnstone of ANSIR supervised the contract.

No abstract available