Tropical Cyclone (TC) Yasi crossed Queensland's Cassowary Coast during the night of the 2nd and 3rd of February, 2011. The cyclone was forecast by BoM (2011) to be a severe storm with wind gusts forecast to exceed the design gust wind speeds for houses set out in AS4055. Following the passage of the cyclone, it was evident that the severe wind and large coastal storm surge had caused significant damage to the region's building stock. Geoscience Australia (GA), together with collaborators from the National Institute of Water and Atmospheric Research, New Zealand (NIWA), Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) and Maddocks & Associates, undertook a survey of damage to the region's buildings caused by severe wind and storm surge.

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Modern geodetic techniques, especially the Global Positioning System (GPS) have allowed the accurate determination of the Earth's surface deformation of Glacial Isostatic Adjustment (GIA) associated with the ongoing stress release of the viscoelastic mantle after removal of the Late Pleistocene ice-sheets. We present an inversion analysis of the GPS derived deformation in North America to determine the effective lithosphere thickness and mantle viscosity, and examine whether the GPS observations can be fit with the ice-sheets and earth models, which were constructed and inferred mainly from geomorphologic/geological and relative sea level (RSL) data. The inversion computation is conducted for horizontal and vertical deformation, separately and jointly with two ice-sheet models (ANU-ICE and ICE-5G) developed independently by the Australian National University (ANU) and University of Toronto. The results from a simple three-layer earth model give a lithosphere thickness of 100~130km, an upper-mantle viscosity of 7~10 × 1020 Pa s, and a lower-mantle viscosity of 1.5~2.8 × 1021 Pa s. More sophisticated models such as introducing a transition zone of 400-670km failed to improve model fit, and the related parameters are mostly consistent with those of three-layer models. Further tests show that models of a thin-layer (30~40km) of large viscosity (~1022 Pa s) did not provide a better fit to the data. Ice scaling tests show that vertical deformation is more sensitive to local ice configuration. An increase of ice thickness by ~40% in Alberta and a reduction by ~50% between Saskatchewan and West Ontario are required to fit both horizontal and vertical deformation observed in Southwest Canada, whereas a reduction of ice thickness by ~25% for ANU-ICE produced an improved fit to both horizontal and vertical deformation in Quebec. Results from inversion analysis of two sub-datasets in Southwest and Southeast Canada revealed a 40% difference in the lower-mantle viscosity, which indicates that the lower-mantle in Southeast Canada could be relatively stronger. There is a discrepancy in the upper-mantle viscosity estimate between horizontal and vertical deformation: a low value (3~5 × 1020 Pa s) required by vertical deformation, and a high value (~9 × 1020 Pa s) favoured by horizontal deformation, which is due possibly to under-represented vertical deformation in the region as well as uncertainties in local ice topography. Overall, the earth model estimated from inversion analysis of GPS data in North America is consistent with the early inference from forward analyses of RSL data (e.g. Tushingham & Peltier, 1992): the lower-mantle viscosity is a factor of 1.5~2.0 larger than upper-mantle viscosity of ~1021 Pa s, reflecting that the main features of the earlier constructed North American ice-sheets (e.g. ICE-3G) are unchanged after two decade refinements.

This study brings together a wide range of datasets to provide a comprehensive assessment of the Pandurra Formation sedimentology and geochemistry in 3D. Sedimentology and geochemistry datasets generated this study are combined with pre-existing data to generate a 3D interpretation of the Pandurra Formation and improve understanding of how the Pandurra formation as we see it to today was deposited and subsequently post-depositionally mineralised.

Collaboration between Geoscience Australia and the Attorney Generals Department. The map series depicts local government areas in SA eligible for NDRRA assistance following natural disasters.

An integrated multi-scale approach has been used to map and assess shallow (<100m) aquitards in unconsolidated alluvial sediments beneath the Darling River floodplain. The study integrated a regional-scale (7,500km2) airborne electromagnetics (AEM) survey with targeted ground electrical surveys, downhole lithological and geophysical (induction, gamma and nuclear magnetic resonance (NMR)) logging, hydraulic testing and hydrogeochemistry obtained from a 100 borehole (7.5km) sonic and rotary drilling program. Electrical conductivity mapping confirmed a relatively continuous lacustrine Blanchetown Clay aquitard, mostly below the water table. The Blanchetown Clay is typically 5-10m thick with a maximum thickness of 18m but, importantly, can also be absent. Variations (up to 60m) in the elevation of the aquitard top surface are attributed partly to neotectonics, including warping, discrete fault offsets, and regional tilting. Hydrograph responses in overlying and underlying aquifers, laboratory permeameter measurements on cores, and hydrogeochemical data demonstrate where the Blanchetown Clay acts as an effective aquitard. In these areas, the AEM and induction logs can show an electrical conductivity (EC) decrease towards the centre of the clay rich aquitard, contrary to the typical response of saturated clays. Even though the aquitard centre is below the watertable, core moisture data and NMR total water logs indicate very low water content, explaining the relatively low EC response. The NMR logs also indicate that the clay aquitard is partially saturated both from the top and the bottom. This suggests very low hydraulic conductivities for the aquitard resulting in negligible vertical leakage in these areas. This is supported by core permeameter measurements of less than 10-12 m/s.

The Australian Government formally releases new offshore exploration areas at the annual APPEA conference. In 2012, twenty-eight areas in nine offshore basins are being released for work program bidding. Closing dates for bid submissions are either six or twelve months after the release date, i.e. 8 November 2012 and 9 May 2013, depending on the exploration status in these areas and on data availability.

Marine benthic biodiversity can be quantified using a range of sampling methods, including benthic sleds or trawls, grabs, and imaging systems, each of which targets a particular community or habitat. Research studies often incorporate only one of these sampling methods in published results, and the generality of marine biodiversity patterns identified among different sampling methods remains unknown. In this study we use three biological collections obtained during a collaborative survey between Geoscience Australian and the Australian Institute of Marine Science to the Van Diemen Rise in northern Australia: 1) Infauna sampled from a Smith-McIntyre grab, 2) Epifauna sampled from a benthic sled, and 3) Biological communities identified from video. For each dataset, we investigated potential patterns of species richness and community structure in relation to depth, geomorphology, and study area, as well as the relationships between datasets. No gear type yielded data that was strongly correlated with depth, but different patterns were evident among gear types based on study area and geomorphology. Comparisons among datasets indicate that species richness from sleds and grabs are more strongly correlated with each other than with richness from video. Further research is planned to incorporate datasets from other regions and habitats in order to provide a general assessment of sampling methods used in the quantification of benthic marine biodiversity in Australasia.

Widespread flooding and associated damage in south-east Queensland during January and February, 2011 have demonstrated the importance of flood risk assessment. Flood risk assessment requires knowledge of the hazard, nature of properties exposed and their vulnerability to flood damage. Flood risk assessment can addresses different aspects of flood risk, i.e., hydrological, structural, economic and social aspects. This report presents the results of work undertaken by Geoscience Australia during 2011-2012 to further the understanding of the vulnerability of Australian buildings to inundation. The work consists of three parts: 1. Development of vulnerability curves for inundation, without velocity, of residential homes of the types encountered during surveys following the January, 2011 flooding in south-east Queensland. 2. Development of vulnerability curves for inundation, without velocity, of building types typical of the Alexandria Canal area of the inner south of Sydney. 3. Development of vulnerability curves for inundation with velocity (storm surge) of residential homes of the types encountered during surveys following TC Yasi, February, 2011.

The lower Darling Valley contains Cenozoic shallow marine, fluvial, lacustrine and aeolian sediments including a number of previously poorly dated Quaternary fluvial units associated with the Darling River and its anabranches. New geomorphic mapping of the Darling floodplain that utilises a high resolution LiDAR dataset and SPOT imagery, has revealed that the Late Quaternary sequence consists of scroll-plain tracts of different ages incised into a higher more featureless mud-dominated floodplain. Samples for OSL (Optically-Stimulated Luminescence) and radiocarbon dating were taken in tractor-excavated pits, from sonic drill cores and from hand-auger holes from a number of scroll-plain and older floodplain sediments in the Menindee region. The youngest, now inactive, scroll-plain phase, associated with the modern Darling River, was active in the period 5-2 ka. A previous anabranch scroll-plain phase has dates around 20ka. Indistinct scroll-plain tracts older than the anabranch system, are evident both upstream and downstream of Menindee and have ages around 30ka. These three scroll-plain tracts intersect just south of Menindee but are mostly separated upstream and downstream of that point. Older dates of 50 ka, 85 ka and >150 ka have been obtained from lateral-migration sediments present beneath the higher mud-dominated floodplain. Establishing a chronology for the Quaternary fluvial landscape has been important for groundwater investigations in the Darling River floodplain area. More specifically, this has assisted in constraining the 3D mapping of floodplain units, helped constrain conceptual models of surface-groundwater interaction, and aided in the assessment of managed aquifer recharge options.