Climatic and tectonic controls on sedimentation within glaciated basins

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Episodes of extreme climate change resulting in glacial conditions have affected our planet for almost 3 billion years. The infill of sedimentary basins affected by these past glacial events contains an extremely valuable record of past climatic conditions in addition to tectonic events related to basin evolution. Unfortunately, discriminating the geologic signature of climatic and tectonic controls on sedimentation is difficult and often compromises the accuracy of paleoenvironmental reconstructions. Interpretation of coarse-grained facies types containing deformation structures is particularly challenging as these features may result from glacial processes, subglacial overriding, scouring by icebergs, or seismic shock, and each of these processes has very different paleoenvironmental significance. The objective of the proposed research is to identify sedimentological criteria that can be used to discriminate climatic and tectonic influences on sedimentation in glaciated basins in order to enhance paleoenvironmental analysis and understanding of potential resource distribution. The proposed research will involve field investigation and analysis of sediments within glaciated basins of different ages and tectonic setting. Late Cenozoic glaciomarine sediments of the Yakataga Fm. on Middleton Island, Alaska have accumulated in a tectonically active collisional margin setting over the past 6 million years and contain a long and continuous record of Late Cenozoic glaciation and tectonic activity. The Late Paleozoic Lower Parmeener Supergroup of the Tasmania Basin contains diamictites and fossiliferous siltstones that record the prolonged deglaciation of southern Gondwana under an extensional tectonic regime. Late Quaternary deposits of glacial, lacustrine and fluvial origin have accumulated under glacial and interglacial conditions in the Lake Ontario basin and provide valuable data with which to compare the pre-Quaternary basin infills. This research is not only important for Paleozoic and Quaternary paleoenvironmental analysis but is also valuable for groundwater management at both local and national levels, and provides many opportunities for the training of HQP.