The Geological Survey of Victoria, in collaboration with Geoscience Australia, has undertaken a seismic survey to acquire data to better understand the geology and hydrogeology (groundwater) of South Gippsland.
The survey was overseen by government scientists, with a specialist survey team contracted to do the field work. The results will be used to improve the scientific understanding of the potential impacts of developing onshore gas and will be made publicly available.
A seismic survey provides more information about underground rock layers using the same principle as medical ultrasound scanning, but on a larger scale.
Vibrating plates are pressed to the ground and generate sound waves that transmit through rocks of different composition at different speeds. The echoes of these sound waves are recorded by ground microphones called geophones and are used to generate images. The process is non-invasive and there is no digging or drilling involved.
The images produced from seismic surveys are cross sections of the earth, and geologists use these, along with other data such as gravity maps, to accurately predict the depth of rock features underground. A 3D model of the rocks underground can be constructed from this new data.
There are several fundamental gaps in the scientific knowledge about the geological formations in the Gippsland sedimentary basin. Having a clear picture of the geology of the region is crucial to understanding where and how water moves through the ground.
The Geological Survey of Victoria and Geoscience Australia engaged Terrex Group to undertake a seismic survey in South Gippsland. Data collection began in early June 2015 and lasted approximately four weeks.
Gippsland seismic lines 2015 location map
You can open a full size version of the map.