Between October 2008 and February 2009, Geoscience Australia undertook two major surveys off the coast of Western Australia. Areas of interest included the Mentelle and northern Perth Basins, the Southern Carnarvon Basin, the sourthern Exmouth Sub-basin (Northern arnarvon Basin) and the Wallaby Plateau. These surveys collected a range of data, including 7300 kilometers of industry-standard seismic reflection data and 43000 line kilometers of gravity and magnetic data. In addition to the new data collected, Geoscience Australia has reprocessed 11700 line kilometres of open file 2D seismic data that exists within the survey area. This data is available for purchase as part of the Southwest Margin Data Package.

Prior to the development of Australian-specific magnitude formulae, the 1935 magnitude corrections by Charles Richter – originally developed for southern California – was almost exclusively used to calculate earthquake magnitudes throughout Australia prior to the 1990s. Due to the difference in ground-motion attenuation between southern California and much of Australia, many historical earthquake magnitudes are likely to be overestimated in the Australian earthquake catalogue. A method has been developed that corrects local magnitudes using the difference between the original (inappropriate) magnitude corrections and the Australian-specific corrections at a distance determined by the nearest recording station likely to have recorded the earthquake. These corrections have reduced the rates of local magnitudes of 4.5 in the historical catalogue by about 30% since 1900, while the number of magnitude 5.0 earthquakes has reduced by about 60% in the same time period. The reduction in the number of moderate-to-large-magnitude earthquakes over the instrumental period yields long-term earthquake rates that are more consistent with present-day rates, since the development of Australian-specific magnitude formulae. The adjustment of historical earthquake magnitudes is important for seismic hazard assessments, which assume a Poisson distribution of earthquakes in space and time.

No abstract available

Scanned felt reports from 1902, 1954-2010. One pdf per event.

Scanned enquires and insurance claims requesting information about South Australian Earthquake or Seismic data for teleseismic events. 1959-1987

The GEOPHYS_SURV database describes geophysical surveys (air, land, and marine), the datasets derived from those surveys, and the methods used for delivery of those datasets. The database includes metadata for all surveys conducted or managed by Geoscience Australia and its predecessor agencies, as well as data and surveys from State and Territory geological survey agencies.

This data set consists of processed seismic reflection data for line 01AGS-NY1 from the 2001 Northern Yilgarn seismic survey (L154), Western Australia. Line 01AGS-NY1 commenced in the Yilgarn Craton (Leonora) and extended to the east into the Officer Basin (east of Lake Yeo). The data were acquired by the Australian National Seismic Imaging Resource (ANSIR) using vibratory sources at a nominal 60 fold coverage. The seismic data are provided as SEG-Y files of stack and migrated data to 4 seconds and 18 seconds two-way time, at a sample interval of 4 milliseconds. CDP range is 1985 to 20860 with 20 metre CDP interval. SEG-Y header information, CDP coordinates as eastings and northings, and a pdf image of the migrated 18 second seismic section are also included. The line, migrated section images and further information on this data can be obtained from the <a href="http://www.pmdcrc.com.au" target="_blank">pmd*CRC</a> website.

TBA

This is a preliminary discussion

No abstract available