Clastic provenance studies in New Zealand

To determine "source to sink" provenance and dispersal of sand in the Taranaki Basin, for prediction of petroleum reservoir sand distribution and quality, via fingerprinting sand composition in modern rivers and coastal areas associated with mapped basement terranes in the basin's southern hinterland to provide an analogue model for ancient sediment sources and effects of sediment transport. Rationale: The proposed study will help to understand and predict the reservoir quality of subsurface sandstone reservoirs in the Taranaki Basin region of New Zealand. These sandstone units were likely sourced from paleo-river systems developed on uplifted basement terranes, equivalents of which crop out today in the Nelson region of South Island, New Zealand. Point counting modern sand sourced from these outcrop areas is an obvious and direct way to document sand that would have potentially entered the marine environment from analogous highlands and, arguably, then supplied to the Taranaki basin in the Cretaceous, Paleogene and Neogene. Modern streams and beaches developed on specific terranes in the Nelson area will be sampled to help quantify the detrital signatures of each major terrane, through modal petrographic analysis. Scope: Funds requested will support graduate/undergraduate student(s) who will be processing (sieving for sand fractions) and conducting preliminary petrographic analysis of thin sections of New Zealand samples. These samples are river and coastal sand samples associated with specific mapped basement terranes that were previously collected by K.M. Marsaglia. The goal is to develop a modern analogue picture of each terrane's relative contribution of monomineralic and lithic grains.