Great Lakes
Earth Exchange

Ashley Scott
Ph.D. Candidate, Department of Geological & Environmental Sciences, Western Michigan University

Reading the Rocks: Evaluating How, Where, When, and Why Dolomite Forms in Peritidal Carbonates
For over a century, geologists have debated how, where, when, and why dolomite forms, largely because modern analogues are rare, geochemical proxy data can be ambiguous, and laboratory synthesis of dolomite at Earth’s surface conditions is challenging. This talk explores dolomitization in shallow marine peritidal carbonates through the lens of the Upper Ordovician Saluda Formation. By combining high-resolution petrographic, geochemical, and mineralogical analyses, this study tests previously proposed diagenetic models and evaluates the timing, fluids, and mechanisms involved during dolomitization of the Saluda Formation. The results offer new perspectives on the origin of dolomite in shallow marine environments and contribute to broader discussions of carbonate diagenesis.

October 29, 2025, 2:00 PM, Strong Hall, Room 111

Madeline Sigler
M.S. Candidate, Department of Earth & Environmental Sciences, Michigan State University

Beneath the Basin: Advancing Groundwater Modeling in the Laurentian Great Lakes
The Great Lakes Basin (GLB) contains over 20% of the world's fresh surface water, comprising 95% of the U.S. freshwater supply, and the region’s groundwater dynamics remain insufficiently understood. A comprehensive basin-scale characterization of groundwater as a regional resource at the basin scale has yet to be established, thus the primary objective of this study is to represent groundwater in the GLB as a regional resource in its entirety, congruent with the extent of the basin watershed. Results from this study will contribute to our understanding of groundwater’s role in the GLB’s hydrologic system and advance our conceptualization of a regional-scale water balance. These simulations will provide essential information for further investigations into groundwater storage, discharge volumes to streams, and baseflow contributions to the lakes.

November 12, 2025, 2:00 PM, Strong Hall, Room 111

Stacy Tchorzynski
Professional Archaeologist & EMU Alum, Michigan Department of Natural Resources

Partners in Time: Earth Science and Archaeology in the Great Lakes Region

February 17, 2026, Time and Location TBD

Sydney Louden
Ph.D. Candidate, Department of Earth & Environmental Sciences, University of Rochester

The oxidation of methane in the Great Lakes is controlled by temperature and inter-lake differences

March 18, 2026, Time and Location TBD