Seismic survey to unlock mineral secrets of the Kimberley
“Understanding the Earth’s basic structure will allow the responsible and informed search for natural resources, including groundwater,” Mines and Petroleum Minister Bill Marmion said.
“It represents one of a series of surveys across Australia as part of the National GeoTransect Program to build a three-dimensional image of the Australian continent, and its evolution.”
The project, funded by the State Government, involves a 700km seismic survey along the Great Northern Highway and the Gibb River Road, from 150km north of Port Hedland to 120km east of Derby.
Seismic reflection waves are generated by vibrating the ground using three large, specialised Vibroseis trucks. The waves travel down through the Earth and are reflected back from geological strata and fault structures that mark changes in rock type. The seismic waves take longer to return from deeper reflectors so the depth of each layer can be determined.
As the survey progresses, an image is built up showing a vertical slice through the Earth’s crust. Listening for up to 20 seconds at each recording point allows imaging of the base of the crust and possibly even into the Earth’s mantle.
“Researchers will be trying to establish the extent and nature of the Canning Basin’s sub-basins and troughs as well as identifying any regional faults, folds and other major structural elements,” Mr Marmion said.
Where possible, the survey will be conducted on the road verge to minimise disruption to traffic and prevent any damage to the road surface. The survey will take between six and eight weeks, depending on weather conditions. Safety signs and potential speed restrictions may be put in place over 25km sections of road, with daily changes as it progresses.