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  • <p>Geoscience Australia conducted the Gunnedah Basin Seismic Survey during January to April 1991. The major aim of the seismic survey was to record deep seismic reflection data across the Gunnedah Basin and bounding margins. The seismic survey would also address several problems relating to the geometry of structural units and major faults. The survey recorded 253 km of eight-fold Common-Middle-Point (CMP) seismic data. The seismic data have been processed, with the data showing good seismic reflection images of the main structural features targeted in the seismic survey.<p><b>Raw data for this survey are available on request from clientservices@ga.gov.au - Quote eCat# 74952</b>

  • <p>Geoscience Australia conducted a seismic reflection survey in various localities throughout Tasmania between January and April 1995. This seismic survey formed part of AGSO project `TASGO' (b103201), a National Geoscience MappingAccord (NGMA) project carried out in conjunction with the Tasmanian Geological Survey (within Tasmania Development and Resources). The seismic survey obtained 134 km of 10 to 20 fold common mid-point (CMP) deep reflection seismic data along six traverses over an 8 week acquisition period. In addition, gravityobservations were made by the Tasmanian Geological Survey at 120 m intervals along five of the lines. Statewide aeromagnetic data has been interpolated to provide profiles along eachseismic line, and shot hole cuttings and water samples were taken for later analysis. The reflection crew provided support for AGSO's refraction and tomography data acquisition which is reported separately.<p><b>Raw data for this survey are available on request from clientservices@ga.gov.au - Quote eCat# 74942</b>

  • Geoscience Australia conducted the Yilgarn-Officer-Musgrave 2D Seismic Survey. The survey involves the acquisition of seismic reflection over the Yilgarn Craton, Officer Basin and Musgrave Province of Western Australia. The survey consisted of one line, totalling 484.2 kms. The project is a collaborative project between Geoscience Australia and the Geological Survey of Western Australia and is part of the ongoing cooperation under the National Geoscience Agreement (NGA). Funding of this project is through the Western Australian Government's Royalties for Regions Exploration Incentive Scheme and Geoscience Australia's Onshore Energy Security Program. The primary objective of the project is to image the western Officer Basin, one of the Australia's underexplored sedimentary basins. In addition this survey will gather new data to improve the understanding of the Yilgarn Craton and its boundary with the Musgrave Province. Raw data for this survey are available on request from clientservices@ga.gov.au

  • Seismic and navigation data for selected lines from seismic surveys T69A and T70A in SEGY format.

  • We report four lessons from experience gained in applying the multiple-mode spatially-averaged coherency method (MMSPAC) at 25 sites in Newcastle (NSW) for the purpose of establishing shear-wave velocity profiles as part of an earthquake hazard study. The MMSPAC technique is logistically viable for use in urban and suburban areas, both on grass sports fields and parks, and on footpaths and roads. A set of seven earthquake-type recording systems and team of three personnel is sufficient to survey three sites per day. The uncertainties of local noise sources from adjacent road traffic or from service pipes contribute to loss of low-frequency SPAC data in a way which is difficult to predict in survey design. Coherencies between individual pairs of sensors should be studied as a quality-control measure with a view to excluding noise-affected sensors prior to interpretation; useful data can still be obtained at a site where one sensor is excluded. The combined use of both SPAC data and HVSR data in inversion and interpretation is a requirement in order to make effective use of low frequency data (typically 0.5 to 2 Hz at these sites) and thus resolve shear-wave velocities in basement rock below 20 to 50 m of soft transported sediments.

  • <div>We performed an earthquake risk assessment of the state of Tasmania through a collaboration between the Tasmania Department of State Growth and Geoscience Australia with geotechnical and geological support from Mineral Resources Tasmania (MRT). We developed local surface earthquake hazard maps for Tasmania, focusing on the twenty largest communities, based on the 2018 National Seismic Hazard Assessment and seismic site conditions map for Australia augmented by geotechnical information provided by MRT. For the building exposure database, the National Exposure Information System was augmented with an engineering survey of Hobart central business district (CBD) undertaken by GA. We used GA’s current vulnerability functions including a range of models for high-risk unreinforced masonry buildings (URM). With a focus on the Hobart CBD, retrofit measures were applied to the URM building types in order to quantify the effectiveness of mitigation. This study provided a synoptic state-wide view that enabled the identification of communities of high risk and low resilience by combining the damage related risk with the Australian Disaster Resilience Index. In addition, three earthquake scenario events centred on Hobart were modelled along with the impact reduction achieved through a virtual retrofit of old URM buildings in the Hobart CBD.&nbsp;</div><div><br></div>This paper was presented to the 2022 Australian Earthquake Engineering Society (AEES) Conference 24-25 November (https://aees.org.au/aees-conference-2022/)

  • The Bureau of Mineral Resources, Geology and Geophysics (BMR) did a reconnaissance seismic survey in the central portion of the Bowen Basin in November, 1960. The objectives of the survey were to determine the structure of the Basin and the thickness of sediments by traversing from the western margin of the Basin near Anakie to the eastern margin east of Duaringa. Two other seismic surveys conducted in this Bowen Basin are Cooroorah Anticline seismic survey in 1959 (survey L037) and 254km seismic survey near the towns of Duaringa and Blackwater (survey L129).

  • Processed Stacked and Migrated SEG-Y seismic data and section images for the Youanmi Deep Crustal Seismic Survey. This survey was conducted under a National Geoscience Agreement with the Western Australia Geological Survey. Funding was through the Onshore Energy Security Program and Western Australia's Exploration Incentive Scheme. The objective of the survey was to image the northwest Yilgarn Craton to the Ida Fault crossing the Meekatharra structural zone, a focus of gold mineralization. Data are supplied as SEG-Y files, TIFF and PDF images. Raw data for this survey are available on request from clientservices@ga.gov.au

  • We report four lessons from experience gained in applying the multiple-mode spatially-averaged coherency method (MMSPAC) at 25 sites in Newcastle (NSW) for the purpose of establishing shear-wave velocity profiles as part of an earthquake hazard study. The MMSPAC technique is logistically viable for use in urban and suburban areas, both on grass sports fields and parks, and on footpaths and roads. A set of seven earthquake-type recording systems and team of three personnel is sufficient to survey three sites per day. The uncertainties of local noise sources from adjacent road traffic or from service pipes contribute to loss of low-frequency SPAC data in a way which is difficult to predict in survey design. Coherencies between individual pairs of sensors should be studied as a quality-control measure with a view to excluding noise-affected sensors prior to interpretation; useful data can still be obtained at a site where one sensor is excluded. The combined use of both SPAC data and HVSR data in inversion and interpretation is a requirement in order to make effective use of low frequency data (typically 0.5 to 2 Hz at these sites) and thus resolve shear-wave velocities in basement rock below 20 to 50 m of soft transported sediments.