Gunflint Range

The Gunflint Range is an iron ore deposit in northern Minnesota in the United States and Northwestern Ontario, Canada.

The range extends from the extreme northern portion of Cook County, Minnesota into the Thunder Bay District, Ontario.

The Gunflint Iron Formation is a continuation of the Mesabi Range to the southwest.

[2][3] The Gunflint Iron Formation is overlain by "brecciated and complexly deformed iron formations", which in turn is overlain by ejecta from the "Sudbury meteorite impact event."

Stromatolite structures are evident within the Gunflint Iron Formation.

Lake Superior Iron Ranges
Shaded-relief image showing Duluth Complex arcing from Duluth to Pigeon Point, interrupting and splitting the Mesabi and Gunflint Ranges