Date of Award
2026
Document Type
Open Access Master's Thesis
Degree Name
Master of Science in Geology (MS)
Administrative Home Department
Department of Geological and Mining Engineering and Sciences
Advisor 1
Chad Deering
Committee Member 1
Snehamoy Chatterjee
Committee Member 2
James DeGraff
Abstract
The geodynamic processes associated with the onset of global plate tectonics remain a contentious topic in Earth Sciences. The Superior Craton of south-central Canada is the largest preserved area of known Archean material, and study of this area has contributed greatly to our understanding of these early Earth processes. The study area near Three Lakes, Michigan, was designated by the USGS as part of the Earth Mapping Resources Initiative (EMRI) program. No complete, detailed geologic map currently exists for the assigned area, and by contributing to mapping efforts, this study was able to assess both the Archean tectonic evolution and initial economic potential of the region. By considering the geography, major and trace element geochemistry, zircon dates, and zircon trace element chemistry of the Tonalite-Trondhjemite-Granodiorite (TTG) suite rocks from this area, evolution of this region is similar to that of the Wawa sub-province of the Superior Craton in Canada. Both regions display a transition from relatively dry to hydrous magmatic source material alongside increased compressional indicators from 2760-2680 Ma. These findings are consistent with the models proposed by Nymoen et al. (2025) and Mole et al. (2021) suggesting that the onset of subduction-related plate tectonics in the region occurred between 2720-2690 Ma. The geochemical properties of this region largely parallel those of the Wawa subprovince by lacking strong geochemical indicators of economic mineral deposits. However, a small prospective locality can be found in the western portion of the study area, which indicates suitable critical mineral porphyry through zircon trace element chemistry. Future work integrating isotopic systems (e.g., Hf–O in zircon) and expanded sampling across the western domain could further refine the developing tectonic model.
Recommended Citation
Foldenauer, Helen Ann, "GEOCHEMICAL, TECTONIC, AND TEMPORAL EVOLUTION OF THE SOUTHEASTERN SUPERIOR CRATON: INSIGHTS FROM THE THREE LAKES REGION, MICHIGAN", Open Access Master's Thesis, Michigan Technological University, 2026.