In a collaborative effort with the regional sub-commissions within IAG sub-commission 1.3 'Regional Reference Frames', the IAG Working Group (WG) on 'Regional Dense Velocity Fields' (see http://epncb.oma.be/IAG) has made a first attempt to create a dense global velocity field. GNSS-based velocity solutions for more than 6000 continuous and episodic GNSS tracking stations, were proposed to the WG in reply to the first call for participation issued in November 2008. The combination of a part of these solutions was done in a two-step approach: first at the regional level, and secondly at the global level. Comparisons between different velocity solutions show an RMS agreement between 0.3 mm/yr and 0.5 mm/yr resp. for the horizontal and vertical velocities. In some cases, significant disagreements between the velocities of some of the networks are seen, but these are primarily caused by the inconsistent handling of discontinuity epochs and solution numbers. In the future, the WG will re-visit the procedures in order to develop a combination process that is efficient, automated, transparent, and not more complex than it needs to be.

These products form part of the exhibition celebrating GA's involvement in the ACT and are produced as part of the ACT centenary.

The Corporate Administrative Records Collection of Geoscience Australia (GA) is a bi fold collection; consisting of electronic/digital documents and records in physical paper format. The digital collection consists of electronic information, which may be "born digital" (created using computer technology) or converted into digital form from their original format (e.g. scans of paper documents). These records are created by all GA employees and are evidence of business conducted by GA and its predecessors. The location of these digital records is in TRIM (electronic document management system). This product treats documents and records in the same way, so that end users perform the same task on all items that are stored in the system, irrespective of whether the item is a document or is to be declared as a record. The digital records can be captured in any format; e.g. excel document, word document, pdf document, emails, etc. When a user saves a document for the first time in TRIM they are prompted for metadata, which is then used to create the record.

No abstract available

This includes collection of core from sonic drilling and soil and water samples from boreholes and surface water. The Core is stored in plastic in core trays (4 x 1m). The water samples are disposed of once analysed.

Please contact education@ga.gov.au for information regarding the availability of this product.

A short article describing the outcomes of the Tasman Frontier Petroleum Industry Workshop held at Geoscience Australia on 8 and 9 March 2012.

The Corporate Administrative Records Collection of Geoscience Australia (GA) is a bi fold collection; consisting of electronic/digital documents and records in physical paper format. GA's corporate administrative records in physical format are created by the Records Management Unit upon request from staff members when their needs meet specific criteria. The files themselves are bound in cardboard folders and labelled and bar-coded according to their respective classification level and metadata information. Individually, the files are a detailed narrative of specific business activities; describing all of the administrative processes that occurred during an activity. The collection is organised according to a year series system; a method which has been constant throughout GA's evolution. The collection also consists of inherited physical records from various government departments. These include the AFFA series from the Department of Agriculture, Forestry and Fisheries Australia and the UB Series, sourced from the Uranium Branch. In collaboration with the relevant government departments, GA acceded custody of these series, and they are now managed in juxtaposition with the entire GA collection.

A key component of Geoscience Australia's marine program involves developing products that contain spatial information about the seabed for Australia's marine jurisdiction. This spatial information is derived from sparse or unevenly distributed samples collected over a number of years using many different sampling methods. Spatial interpolation methods are used for generating spatially continuous information from the point samples. These methods are, however, often data- or even variable- specific and it is difficult to select an appropriate method for any given dataset. Machine learning methods, like random forest (RF) and support vector machine (SVM), have proven to be among the most accurate methods in disciplines such as bioinformatics and terrestrial ecology. However, they have been rarely previously applied to the spatial interpolation of environmental variables using point samples. To improve the accuracy of spatial interpolations to better represent the seabed environment for a variety of applications, including prediction of biodiversity and surrogacy research, Geoscience Australia has conducted two simulation experiments to compare the performance of 14 mathematical and statistical methods to predict seabed mud content for three regions (i.e., Southwest, North, Northeast) of Australia's marine jurisdiction Since 2008. This study confirms the effectiveness of applying machine learning methods to spatial data interpolation, especially in combination with OK or IDS, and also confirms the effectiveness of averaging the predictions of these combined methods. Moreover, an alternative source of methods for spatial interpolation of both marine and terrestrial environmental properties using point survey samples has been identified, with associated improvements in accuracy over commonly used methods.

Please note: This product has been superseded by 50m Multibeam Dataset of Australia 2018. - This tile contains all multibeam data held by Geoscience Australia on August 2012 within the specified area. The data has been gridded to 50m resolution. Some deeper data has also been interpolated within the mapped area. The image provided can be viewed on the free software CARIS Easyview, available from the CARIS website: www.caris.com under Free Downloads.