Earth Imaging & Sounding Kit
Australian Seismological Reference Model AuSREM (AuSREM)
AuSREM was designed to bring together existing information on the Australian continent of many types, and provide a synthesis in the form of a 3D model that can form the basis for future refinement from more detailed studies.
Seismological models of the Earth’s crust and upper mantle structure are critical for many tasks, such as the calculation of earthquake source parameters (location, magnitude, geometry), mapping the distribution of shaking after earthquakes, and the imaging of lithospheric dynamic processes.
AuSREM is designed to bring together the diverse sources of information about the structure under the Australian region. The emphasis is on the Australian continent, but with mantle coverage to the local boundaries of the Australian plate.
Seismic Data Loggers
The Earth Sounding program at ANU involved the acquisition of Earth Data Recorders which became field ready in December 2012 and are now in heavy use both in Australia and New Zealand and the construction of 200 new generation Seismic Data Loggers, with very low power consumption. From October 2014 these new instruments formed the backbone of two arrays in northern New South Wales and Southern Queensland and another in Western Australia. The third strand involved the acquisition of 50 Trillium Compact Seismometers that have been delivered and made field ready. These instruments are being used in one of the Queensland arrays and in the Western Australian array.
Australian National Ocean Bottom Seismometer (OBS)
The establishment of an OBS fleet was a new initiative of AuScope. 20 OBS units were delivered, tested and accepted. Eight units were tested in deep water and the remainder in moderate depths. In January 2015 a very successful OBS survey was completed on the Australian North West Margin during which further testing of the capability of the instruments, to record meaningful geophysical data from airgun seismic source to large offsets, was completed and far exceeded results from previous trials. The survey was sponsored by Shell Australia and conducted by geophysical contractor CCG. The Shell/CGG OBS survey has been the largest OBS recording campaign so far using the new Australian National OBS Fleet. The campaign lasted from 30 November 2014 to 17 January 2015 and included 20 OBS deployments and recoveries; no instruments were lost during the survey. During the campaign at least two major milestones were achieved:
Instruments were deployed and recovered in record water depth exceeding 2000 m (2425 m maximum at site BART 1).
Some instruments stayed in the water continuously and recorded data for almost 47 days thus achieving the record duration of deployment of the Australian National OBS Fleet so far.
The Australian National OBS Pool is fully operational and ready for use on a variety of projects by academia, government organisations and our industry partners. The units are stored by Geoscience Australia.
Magnetotelluric field instruments
In Adelaide a fleet of 100 electric and magnetic MT field instruments was built and made fully available to the Australian Geophysical community. These instruments are currently deployed in a major geophysical monitoring experiment in Queensland.
As. Prof. Meghan Miller
Australian National Uni
For more information on current and potential projects or accessing AuScope’s Earth Imaging and Sounding infrastructure component please get in touch with Meghan.
Dr. Graham Heinson