Copper Harbor along the Lake Superior

The Copper Harbor Conglomerate in Northern Wisconsin and the Upper Peninsula of Michigan formed in an ancient rift valley 1.1 billion years ago when Amazonia (Precambrian Shield of NE South America) rifted away from Laurentia (Precambrian North America). This unit contains abiotic and biotic stromatolites and biomats that are some of the oldest preserved evidence for life on land. The conglomerate was part of a thick alluvial fan succession that filled the rift valley. It contains deposits of ancient river channels, sheet flow and lake deposits. In some cases, single samples of rock contain ripple marks, desiccation cracks, and rain-drop imprints, which records the complexity of these strata.

Research

Jenny Ulbricht is working on these deposits for her M.S. research projects while undergraduate students Liz Borucki and Stefanie Dodge have helped her with her field work. Jenny is working under the direction of Dr. John Isbell.

Nick Fedorchuk (Ph.D. student) and former undergraduate student Dylan Wilmeth have worked on the fossils from this unit under the direction of Dr. Stephen Dornbos to better understand life’s invasion of land.

Dr. Julie Bowles is beginning to investigate the paleomagnetism in these units to better understand the tectonics of the rift and the climatic history of that time period.

Future students may have the opportunity to work on various problems associated with these rocks under the directions of Dr. Bowles, Dr. Dornbos, and Dr. Isbell.