Stromatolites
North of the Great Lakes lies the Canadian Shield, a very ancient geologic feature that bears Banded Iron Formation (BIF). Formed 4 to 2.5 billion years ago, BIF is among Earth’s oldest rock formations. Some BIF contains fossils of Earth’s earliest life, stromatolites, which were algae mats formed on ancient seas. In recent Ice Ages, the glaciers that scoured the Canadian Shield brought rocks containing BIF and stromatolites to the southern shores of the Great Lakes.
NASA’s Perseverance rover landed on Mars on February 18, 2021. Its mission, in part, is to look for stromatolites. How lucky I am to find ancient BIF containing stromatolites along Lake Michigan’s Left Coast.
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About the Author
Elizabeth G Fagan is a writer and artist who resides on Lake Michigan’s shoreline in southeastern Wisconsin—a place she calls Lake Michigan’s Left Coast. She has been a professional writer for more than 35 years.
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Contact Elizabeth G Fagan
Fagan attended The Hammonasset School, a private arts high school in Connecticut, where she began writing and taking photographs. She earned a BA in English at Grinnell College (Grinnell, Iowa) and the University of Illinois, Chicago (UIC). She has an MA in Linguistics with a specialization in teaching English as a second language (ESL) from UIC. Fagan later gained an associate degree in Web Development from DePaul University in Chicago.
- “Art from Lake Michigan’s Left Coast,” Grinnell College Alumni Association
- Cedarburg Artists Guild
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