Four posters describing work being undertaken in Antarctica: VULNERABLE MARINE ECOSYSTEMS IN ANTARCTICA SEABED MAPPING IN ANTARCTICA DEFINING ABSOLUTE GRAVITY AN ANTARCTIC GEODESY

This poster shows earthquakes occurring in Australia in 2011 with a background of earthquakes occurring in Australia over the past 10 years. Also included are images produced as part of the analysis of the Bowen Earthquake and its associated aftershocks as well as the yearly summary of earthquake occurrences in Australia.

As part of the National CO2 Infrastructure Plan, Geoscience Australia is undertaking a three year project to provide a detailed assessment of the Vlaming Sub-basin prospectivity for the geological storage of CO2. An important part of this assessment is an evaluation of the seal quality and integrity, including analysis of fault reactivation, signs of seepage, as well as lithological variability within the seal. Over a large area the Gage reservoir is underlain by the Charlotte reservoir (Figure 1). Based on well data, the two reservoirs are at least partially connected. Due to limited data, the Charlotte reservoir was not considered by the previous studies for additional storage capacity. Even if Charlotte Sandstone is not considered for storage, it presents a base seal issue for CO2 storage in the Gage reservoir, which needs to be addressed. The current study mapped the Charlotte reservoir and analysed its potential impact on the containment of CO2. Initial results of this study are outlined below.

Geoscience Australia is the national mapping agency, providing fundamental geoscientific data in support of mineral and petroleum exploration.

This map is an attractive representation of the relief of Australia with north-west illumination. The elevation image was derived from Geoscience Australia`s GEODATA 9 Second Digital Elevation Model (DEM) with a grid spacing of 9 seconds of latitude and longitude (approximately 250 metres on the ground). Over 5 million spot height values were used in the generation of the DEM.

Forward modelling was undertaken to test the architecture of the Southern Carnarvon deep seismic reflection survey (11GA-SC1) interpretation against gravity data. The seismic data extends to ~60 km depth and images the crust-mantle boundary (Mohorovi-i- discontinuity) allowing it to be incorporated in the forward modelling. Using average density values for the upper mantle, granulite to amphibolite facies mid to lower crustal rocks, and upper crustal felsic and sedimentary rocks, a model was generated which explains the observed gravity anomalies and is consistent with the seismic interpretation. This work highlighted areas where the seismically inferred models were inconsistent with the gravity data and the importance of understanding regional trends, such as those generated by the crust-mantle boundary. The modelling undertaken in this study reflects the most up to date understanding of the regional geology in this area.

Poster for temporary display at Ocean Optics Conference Glasgow 2012

Displayed at Questacon July 21-22

The Joint Australian Tsunami Warning Centre (JATWC) provides 24/7 monitoring of earthquake and tsunami hazards affecting Australia and the Indian Ocean. The JATWC comprises Geoscience Australia, who undertake earthquake monitoring in Canberra, and the Bureau of Meteorology in Melbourne, who issue tsunami bulletins and monitor the sea level. Earthquakes are monitored at Geoscience Australia in real-time via a total network of over 260 seismic stations from both the Australian National Seismic Network (ANSN); and a collection of global stations, collaborating with other earthquake monitoring groups and organisations locally and internationally. This enables the quick detection and response to local, regional and global earthquakes, and assessment of its potential to generate a tsunami. If an earthquake is deemed to be tsunamigenic, earthquake information is used by the JATWC to deliver a tsunami warning based on the magnitude, depth and location of the earthquake combined with tsunami models. These warnings are supplemented with sea level information to validate the tsunami warning. Geoscience Australia also provides earthquake information and advice about Australian earthquakes and large international earthquakes to the Australian Government and general public. This is valuable for building safer communities in a world where the impacts of natural disasters can be far-reaching.

Descriptive posters