This research is aimed at understanding the composition, origin and evolution of the continental crust. The general approach used is the study of the geochemical and isotopic composition of terrigenous sedimentary rocks. Results over the past several years have shown that well behaved systematic behavior exists in the geochemistry of terrigenous sediments that is controlled by a number of factors. Included are sedimentary processes, such as weathering and diagenesis, and provenance considerations, commonly related to plate tectonic associations. In detail however, quantitative understanding of these controlling factors, at a level that allows predictive modelling, remains elusive. The potential of this research is great. The relationship between average sediment composition and average upper crustal composition provides important constraints on overall crustal composition and permits examination of such compositions through time. The crust, generally considered to have been derived from the mantle is a major geochemical reservoir for many elements and, accordingly, such study has direct relevance for studies of mantle and bulk earth evolution. On a more practical level, the study of trace element and isotopic composition in terrigenous sedimentary rocks provides a great deal of additional information, required to quantify relationships between sedimentation and tectonics, than is provided by traditional approaches of sedimentary petrography.
