Tuesday, June 4, 1:00pm

Dr Graham Heinson

Lecturer in Exploration Geophysics, Dept. of Geology & Geophysics, The University of Adelaide

Seafloor Electromagnetic Methods for Petroleum Exploration  


Seismic methods have been extremely successful in petroleum exploration, but have difficulty in locating base salt structure due to attenuation and scatter of signal within the salt body. An alternative method is to use magnetotellurics (MT). This is a natural-source electromagnetic (EM) exploration technique that is beginning to be used in salt imaging for petroleum exploration. Independently, MT is able to resolve gross salt structures, and when complimented with a priori seismic data, MT effectively defines base and horizontal salt boundaries. This seminar will outline the basic principals of the marine MT method and explain how data can be used to image electrical properties of the top few kilometres of the seabed. Examples will be drawn from recent Honours work by Volmer Berens on a marine MT experiment conducted in the northern Gulf of Mexico in 1998 (GOM98). The data collected illustrate the ability of MT to image salt structure both as an individual technique and using complimentary seismic data in two and three-dimensions. Examples of instrumentation developed at Flinders University, and project work to be carried out in the Timor Sea will also be shown.

Biography of the Speaker

Graham Heinson completed a BSc in geophysics from Edinburgh University before migrating south to a warmer climate to do a PhD at ANU. After several postdoc positions in marine geophysics at Flinders University and Tokyo University, he has been a lecturer in exploration geophysics at Adelaide University since 2000.