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Full-Text Articles in Earth Sciences
Evaluating The Biogenicity Of Fluvial-Lacustrine Stromatolites From The Mesoproterozoic Copper Harbor Conglomerate, Upper Peninsula Of Michigan, Usa, Nicholas David Fedorchuk
Evaluating The Biogenicity Of Fluvial-Lacustrine Stromatolites From The Mesoproterozoic Copper Harbor Conglomerate, Upper Peninsula Of Michigan, Usa, Nicholas David Fedorchuk
Theses and Dissertations
The Mesoproterozoic (1.09 Ga) Copper Harbor Conglomerate represents alluvial fan, fluvial and lacustrine deposition in the Midcontinent Rift System. The formation outcrops in the Keweenaw Peninsula in the northwestern part of the Upper Peninsula of Michigan where it contains carbonate stromatolites preserved within both siltstone and conglomerate facies. The purpose of this study is to evaluate the biogenicity of these stromatolites, which lack direct microfossil evidence. The stromatolites were placed into their depositional context, their macro-scale features and thin section microfabrics were analyzed, and growth angles were measured of cobble-draping samples to determine if a phototrophic response existed. A methodology …
Sedimentology And Paleoecology Of Fossil-Bearing, High-Latitude Marine And Glacially Influenced Deposits In The Tepuel Basin, Patagonia, Argentina, Kathryn N. Pauls
Sedimentology And Paleoecology Of Fossil-Bearing, High-Latitude Marine And Glacially Influenced Deposits In The Tepuel Basin, Patagonia, Argentina, Kathryn N. Pauls
Theses and Dissertations
The glacial and non-glacial intervals of the Late Paleozoic Ice Age (LPIA) are of great interest because they are our best deep time analogue for Pleistocene climate change. The changes and adaptations of the biota, as seen in the rock record, can serve as a proxy for understanding future trends in Earth's climate system. Most of the known LPIA marine faunal data come from low-latitudinal regions, and thus have been used as a global proxy. However, modern organisms in the low-latitudes (far-field basins) respond differently to a changing climate relative to marine organisms in the polar regions (near-field basins). In …