The Geological Survey of Victoria (GSV) and Geological Survey of South Australia (GSSA) are acquiring magnetotelluric (MT) data across the Delamerian Orogen in northwest Victoria and southeast South Australia. This project adds to a program of regional pre-competitive geoscience acquisition planned for the region in collaboration with Geoscience Australia and MinEx CRC. Acquisition includes deep crustal reflection seismic, ground gravity and airborne electromagnetic surveys under the national Exploring For The Future program and GSSA-led drilling in South Australia as part of the National Drilling Initiative.
Here, we present the first phase of broadband MT data (periods from 0.0001 s to 1000 s) acquired at a nominal 3-4 km site spacing along a ~350 km-long profile across the Murray Basin from Murray Bridge to Swan Hill in Victoria. A total of 118 stations will be modelled in 2D and 3D to augment and refine publicly available AusLAMP MT models of the region (e.g. Delamerian AusLAMP survey through the GSSA SARIG portal). The new data and models will provide electrical constraints of the entire crust and upper mantle to improve the structural architecture of the Delamerian Orogen and its eastern boundary with the Lachlan Orogen.