Geology of the Gunflint Iron Formation and the Sudbury Impact Layer, Northeastern Minnesota
نویسنده
چکیده
Figure 1. Regional geologic map of northeastern Minnesota showing the location of Gunflint Trail (modified from Jirsa and Miller, 2005). Field trip area lies near the northwestern end of the trail at the junction of Neoarchean, Paleoproterozoic, and Mesoproterozoic terranes.
منابع مشابه
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INTRODUCTION The 2.0 Ga iron-bearing Gunflint Formation was deposited during a transitionary period in Earth history when a stable oxic atmosphere was being established. The Animikie Group, which comprises both the Rove and Gunflint Formations, extends NE-SW for approximately 175 km from Thunder Bay, Ontario to northern Minnesota [1]. The thickness of the Gunflint ranges from 100 to 180 m, with...
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