Avo In Gold Exploration: A South African Case Study

A modification of the Geostack method of AVO analysis as described by Smith and Gidlow (1987) is used in a hard-rock mining ervironment as an aid to distinguishing between volcanic and<br>sedimentary successions on a seismic section. Poisson’s ratios derived from laboratory measurements on sediments and volcanics in the Witwatersrand Basin in South Africa are used to set up “sediment” and “volcanic” lines, equivalent to the “mud-rock” line of Catagna (1985) for clastic silicates. It is demostrated that these sediment and volcanic lines are sufficiently different to allow the Geostack method to distinguish between the sediments and volcanics on both synthetic and real seismic data.