This dataset contains primary geological data, namely Pre-Permian geological rock units and boundary types separating rock units. The linear features in this dataset are only comprised of geological boundaries and faults.
The data has been collected by the Geological Survey of Victoria. This dataset is accompanied by another dataset representing metamorphism.
The pre-Permian geology data from Simons and Moore (1999) shows the interpreted geology of Victoria, with the Permian and younger units stripped off. It was compiled from the surface geology map and interpretation of the extensive new magnetic, radiometric and gravity data along with seismic profiles where available. It attempts to reconcile the mapped geology with the geophysical data sets, to produce a map that is both geologically and geophysically reasonable. The data should be used in combination with the state magnetic image as this image gives extra information that could not be adequately presented on the map, such as sedimentary or contact-metamorphic changes in the magnetic properties of rock packages, dyke swarms, and thick basalt cover.
The legend subdivides the rocks by time and palaeoenvironment or geochemistry, which gives a complementary view of the geology to that of the surface Australian crust during Phanerozoic orogenic events.
Granites were subdivided using White and Chappell's (1983) S, I and A classification, as this is a subdivision that is both generally understood and works well with the magnetic data. The time subdivisions are at the natural breaks in the Victorian geological record, usually the ends of orogenies. This has meant that all the intrusions associated with a particular event are grouped in the same time slice, even when some could perhaps be allocated to a younger time slice.
SIMONS, B.A.., AND MOORE, D.H. 1999. Victoria 1:1 000 000 Pre-Permian Geology. Geological Survey of Victoria.
WHITE, A.J.R. & CHAPPELL, B.W., 1983. Granitoid types and their distribution in the Lachlan Fold Belt, southeastern Australia. In Roddick, J.A. (ed.) Circum-Pacific Terranes, Geological Society of America Memoir 159, pp. 21-34.