Rachel Merz

Date Approved


Degree Type

Open Access Senior Honors Thesis

Department or School

Geography and Geology

First Advisor

Dr. Christine M. Clark

Second Advisor

Dr. Steven T. LoDuca

Third Advisor

Dr. Rick Sambrook


The Deer Lake Peridotite and the Presque Isle Periodotite are two ultramafic formations of Neoarchean age within the Ishpeming Greenstone Belt of Michigan’s Upper Peninsula, and are found only fifteen miles apart. The Deer Lake Peridotite was deformed in processes indicative of the broader, regional-scale tectonics of the region, but little study has been done on the mineralogy and extent and style of alteration. This research aims to better classify the mineralogy of the formation, with particular focus on textural variations observed in thin-section, as well as chemical analysis of samples taken from the formation. In addition, this research seeks to correlate the Deer Lake Peridotite’s history of alteration, which may have included alteration by Proterozoic events, with that of the Presque Isle Black Rocks, a formation which has had more extensive study done on its tectonic history and alteration. The comparison between alteration styles in the two formations will help draw conclusions about the tectonic history of Michigan’s Upper Peninsula.

Included in

Geology Commons