The IAG (International Association of Geodesy) Working Group (WG) on 'Regional Dense Velocity Fields' aims at densifying the ITRF (International Terrestrial Reference Frame) and creating a dense velocity field based on regional and global GNSS networks. With the goal to generate a high-quality solution for a core network, several newly reprocessed global and regional cumulative position and velocity solutions were submitted to the WG. In order to find a consensus on discontinuity epochs for stations common to several networks (an issue which was problematic in previous submissions), the new submissions were restricted to contain only the core networks over which the analyst has full control so that ITRF2008 discontinuities could be applied. The 3D-RMS of the agreement of the new solutions with the ITRF2008 (after outlier rejection) varies between 0.6 and 1.1 mm/yr; it is extremely good for some solutions, while others still require more iteration to reach the required level of precision. Generally the cause of these disagreements has been identified and they often originate in the use of different data time spans within the ITRF2008 and submitted solution. In a next step, the WG expects to generate and use a discontinuity database complementing the ITRF2008 one and identify/solve the sources of disagreements. In addition, several of the regional solutions will be reprocessed to imbed the regional network in a global network and reduce the error induced by the network effect. More details on the WG are available from http://epncb.oma.be/IAG/.

Lord Howe Island in the southwest Pacific Ocean is surrounded by a shallow (20 - 120 m) sub-tropical carbonate shelf 24 km wide and 36 km long. On the mid shelf a relict coral reef (165 km2) extends around the island in water depths of 30 - 40 m. The relict reef comprises sand sheet, macroalgae and hardground habitats. Inshore of the relict reef a sandy basin (mean depth 45 m) has thick sand deposits. Offshore of the relict reef is a relatively flat outer shelf (mean depth 60 m) with bedrock exposures and sandy habitat. Infauna species abundance and richness were similar for sediment samples collected on the outer shelf and relict reef, while samples from the basin had significantly lower infauna abundance and richness. The irregular shelf morphology appears to determine the distribution and character of sandy substrates and local oceanographic conditions, which in turn influence the distribution of different types of infauna communities.

The Glenloth Granite is an icon of South Australian geology, having been the site of some of the earliest gold workings in the central portion of what is now known as the Gawler Craton and the subject of some of the first radiometric age determinations in the 1960's. The Glenloth Granite forms part of the Neoarchaean to earliest Palaeoproterozoic belt of supracrustals and associated intrusives known as the Mulgathing Complex, which includes mafic to ultramafic (komatiitic) volcanics. Inferred to be syn-tectonic in nature in the original 1:250 000 scale mapping of the region, new SHRIMP data shows that the Glenloth Granite was emplaced at 2508 +/- 2 Ma, during period of magmatism that predates the ca. 2470 - 2420 Ma Sleafordian Orogeny. This orogenic event reworked the Glenloth Granite in to magmatitic gneiss and is responsible for two main generations of metamorphic zircon growth at 2453 +/- 4 Ma and 2427 +/- 3 Ma, likely reflecting initial prograde metamorphism followed by migmatite formation during biotite dehydration reactions, as has been documented from elsewhere in the Mulgathing Complex.

We report on an assessment of severe wind hazard across the Australian continent, and severe wind risk to residential houses (quantified in terms of annualised loss). A computational framework has been developed to quantify both the wind hazard and risk due to severe winds, based on innovative modelling techniques and application of the National Exposure Information System (NEXIS). A combination of tropical cyclone, synoptic and thunderstorm wind hazard estimates is used to provide a revised estimate of the severe wind hazard across Australia. The hazard modelling utilises both 'current-climate information and also simulations forced by IPCC SRES climate change scenarios, which have been employed to determine how the wind hazard will be influenced by climate change. We have also undertaken a national assessment of localised wind speed modifiers including topography, terrain and the built environment (shielding). It is important to account for these effects in assessment of risk as it is the local wind speed that causes damage to structures. The effects of the wind speed modifiers are incorporated through a statistical modification of the regional wind speed. The results from this current climate hazard assessment are compared with the hazard based on the existing understanding as specified in the Australian/New Zealand Wind Loading Standard (AS/NZS 1170.2, 2002). Our analysis has identified regions where the design wind speed depicted in AS/NZS 1170.2 is significantly lower than 'new' hazard analysis. These are regions requiring more immediate attention regarding the development of adaptation options including consideration by the wind loading standards committee for detailed study in the context of the minimum design standards in the current building code regulations.

The dual eruption of Tavurvur and Vulcan destroyed the town of Rabaul, East New Britain, Papua New Guinea in 1994. This was primarily due to the effects of ash loading on buildings from the ash fallout of Tavurvur. The eruption of Tavurvur and its ash fallout was well documented and as a result was chosen to validate the volcanic ash modelling software FALL3D. In order to validate FALL3D the modelled output needs to sufficiently replicate the observed data and this was achieved using an inverted wind profile and volcanological data gathered from a literature review. The 1994 eruption was then used as an analogue to investigate the effect a future eruption would have on the surrounding area. It was found that the capital of East New Britain, Kokopo, is in danger of ash fallout during one third of the year while Rabaul is in danger of receiving ash fallout during two thirds of the year based on the dominant wind directions in the area.

Tide gauge data forms the basis for determining global or local sea level rise with respect to a global geocentric reference frame. Data from repeated precise levelling connections between the tide gauge and a series of coastal and inland benchmarks, including a Continuous GPS (CGPS) benchmark, is used to determine the stability of tide gauges at 12 locations in the South Pacific. The method for determining this is based on a constant velocity model which minimises the net movement amongst a set of datum benchmarks surveyed since the installation of the tide gauges. Tide gauges were found to be sinking, relative to the CGPS benchmark, in Pohnpei (FSM), Samoa, Vanuatu, Tonga, Nauru, Tuvalu, Fiji and Cook Is; listed in order of the sinking rate, with a maximum of -1.01 - 0.63 mm/yr at Pohnpei (FSM) and a minimum of -0.03 - 0.81mm/yr at Cook Is. The tide gauge was rising, relative to the CGPS benchmark, in Solomon Is, Manus Is (PNG), Kiribati and Marshall Is, with a maximum of 3.12 - 0.49mm/yr in Solomon Is and a minimum of 0.01 - 0.91mm/yr in Marshall Is. However, these estimates are unreliable for the Solomon Is and Marshall Is, which have recently established CGPS benchmarks and have been surveyed less than 3 times. In Tonga and Cook Is, the tide gauge was found to be disturbed or affected by survey errors whereas the Vanuatu results were affected by earthquakes. It was also found that the constant velocity model did not fit the observations at the tide gauges in Tonga, Cook Is, Fiji, Marshall Is and Vanuatu, which had large variations in their velocities. This is an indicator of the high frequency (short period) motion of the tide gauge structure, which cannot be measured by the levelling method since these have a higher frequency than the time interval between levelling surveys.

Three data sets containing locational and attribute information for places respectively on the Commonwealth, National, and World Heritage Lists determined by the Australian Government Department of Sustainability, Environment, Water, Population and Communities - Heritage Division. Places subject to confidentiality agreements are not included in these data. The Commonwealth Heritage List is a list of natural, Indigenous and historic heritage places owned or controlled by the Australian Government The National Heritage List has been established to list places of outstanding heritage significance to Australia. It includes natural, historic and Indigenous places that are of outstanding national heritage value to the Australian nation. The World Heritage List contains sites selected on the basis of ten cultural and natural criteria under the Convention concerning the Protection of the World Cultural and Natural Heritage, adopted by UNESCO in 1972.

This research utilises metadata from GA's centralised metadata store containing the history of the equipment changes which have taken place at all GNSS stations; such as antenna or receiver swaps, firmware upgrades and removal/ alteration of antenna domes and cables. Several change detection algorithms have been implemented for automatic detection of discontinuities in the coordinate time series. Once offsets are detected, their position in time is correlated with equipment changes or earthquake occurrences nearby the station. If a correlation is found and the offset is visibly evident, the offset is introduced into a database. This information is used in the routine combination of weekly SINEX solutions using the CATREF software to produce an enhanced set of coordinates and velocities. It is shown that after cleansing the offsets in time series using this approach, the quality of the combined APREF solution is improved in terms of WRMS. By analysing time series coordinates at a few stations using CATS software, it is shown that the uncertainty of velocity estimates is improved after offsets are detected and removed from the time series.

In the 2011/12 Budget, the Australian Government announced funding of a four year National CO2 Infrastructure Plan (NCIP) to accelerate the identification and development of suitable long term CO2 storage sites, within reasonable distances of major energy and industrial emission sources. The NCIP funding follows on from funding announced earlier in 2011 from the Carbon Storage Taskforce through the National Carbon Mapping and Infrastructure Plan and previous funding recommended by the former National Low Emissions Coal Council. Four offshore sedimentary basins and several onshore basins have been identified for study and pre-competitive data acquisition.

Dense coral-sponge communities on the upper continental slope (570 - 950 m) off George V Land, east Antarctica have been identified as Vulnerable Marine Ecosystems. We propose three main factors governing their distribution on this margin: 1) their depth in relation to iceberg scouring; 2) the flow of organic-rich bottom waters; and 3) their location at the head of shelf cutting canyons. Icebergs scour to 500 m in this region and the lack of such disturbance is a likely factor allowing the growth of rich benthic ecosystems. In addition, the richest communities are found in the heads of canyons which receive descending plumes of Antarctic Bottom Water formed on the George V shelf, which could entrain abundant food for the benthos. The canyons harbouring rich benthos are also those that cut the shelf break. Such canyons are known sites of high productivity in other areas due to strong current flow and increased mixing with shelf waters, and the abrupt, complex topography.