Stavely Geological Research Project
Gravity Survey Community Fact Sheet
The Geological Survey of Victoria is conducting low-impact geological survey work along roadsides in western Victoria in December 2016.
State and territory geological survey agencies regularly carry out geological and geophysical surveys.
The data collected helps geoscientists, governments and land resource managers to learn about the geology and structure of the earth's crust. The results can assist in understanding the evolution of the landscape, developing models for the movement of groundwater, guiding exploration for minerals and identifying significant geological faults.
Stavely Geological Province
The Geological Survey of Victoria, in collaboration with Geoscience Australia, has been undertaking geoscientific research within the Stavely geological province in western Victoria for several years. Work completed to date indicates the province was once on the border of a super-continent that existed 500 million years ago and has similarities to the present day geology of western South America.
This new round of research will feature a low-impact ground gravity survey along selected public roads and tracks (gravity traverses) around Nhill, Horsham, Stawell, Halls Gap, Willaura and Chatsworth (Figure 1 -map on right). This area has been chosen to help answer specific questions about the distribution of different types of rocks in the province.
What is a 'gravity survey'?
A gravity survey is one of many low-impact geophysical techniques used by geologists to 'see' beneath the earth's surface. A small device (about the size of a suitcase), called a gravity meter, is used to measure very small variations in the earth's gravity field. Some of these variations are the result of density differences between different types of rocks. This information can then be used to map the distribution of the rocks.
How is the survey conducted?
The survey involves a vehicle travelling along specified routes and pulling off to the side of the road every 200 metres for a person to get out and place a gravity meter on the ground to take a gravity measurement. The exercise takes about three to five minutes for each stop. The gravity meter is then put back in the vehicle and moved on to the next site. The meter does not disturb or impact the ground in any way, and apart from footprints/tyre tracks there should be no disturbance.
Care is being taken to protect roadside flora and fauna, and procedures are in place to avoid transport of soil and plant material.
The gravity survey work is overseen by the Department of Economic Development, Jobs, Transport and Resources. A range of other Victorian authorities have also been consulted, such as Parks Victoria, the Department of Environment, Land, Water and Planning, VicRoads and local councils.
About the surveyors
Atlas Geophysics Pty Ltd are experienced gravity survey operators engaged by the Geological Survey of Victoria to conduct the survey and gather the data. The survey teams are driving light diesel, four-wheel-drive vehicles with identifiable markings. A detailed risk assessment has been prepared by the contractor to ensure the safety of the surveyor, other road users and the environment.
What happens to the results?
The data gathered during the survey will be processed and then made publicly available through the Department of Economic Development, Jobs, Transport and Resources and Geoscience Australia websites. The data will also be used to help build a publicly available, digital three-dimensional (3D) geological model to increase understanding of the region's geology and to present this information visually.
If you would like more information about the Stavely gravity survey, please call the Department of Economic Development, Jobs, Transport and Resources' Customer Service Centre on 136 186.