Virtual reconstruction of stratigraphy and past landscapes in the West Coast Fossil Park region
Thesis (MA (Geography and Environmental Studies))--University of Stellenbosch, 2005.
The West Coast Fossil Park near Langebaanweg in the Western Cape, South Africa, is known for its abundance of marine, freshwater and terrestrial fossils of Mio-Pliocene age. The fossil bearing deposits reflect the complex and varied depositional environments, which were influenced by the change in course of the Berg River and regressions and transgressions of sealevel. The fossil deposits at this site are world-renowned for their species richness and uniqueness and there was a need to gain an in-depth understanding of the events that gave rise to this situation. To understand these complexities, it was necessary to construct a composite model of the pre-history of the West Coast Fossil Park, incorporating topological, geological and palaeontological data. GIS provided the ideal platform to integrate data from such varied sources, using spatial correlation to interpret commonalities. Subsequently, a spatially explicit database of the present-day study area, from Dwarskersbos in the north to just north of Yzerfontein in the south, was constructed. The oldest geological formation, the basement layer, as well as three successive formations was reconstructed on a regional scale using borehole data. Interpolation of point data to regional surfaces was a dual process incorporating expert opinion and purpose-built tools within ESRI’s ArcInfo and ArcMap 8.3. A similar reconstruction at a finer scale was done for the West Coast Fossil Park area using kriging as an interpolation method. These reconstructed geological layers can be used to predict the depth and location of fossil-bearing deposits. There is scope for further study and analysis to compare the accuracy of alternative interpolation methods, and combining it with field-based validation of modelled outputs.