Bedrock Geology Map of the Cavity Lake Fire Area: Cook County, Northeastern Minnesota

Abstract

This map is the result of three and a half days of mapping in the Cavity Lake burn area on Gabimichigami Lake. It is the third map in a series of maps produced by the Precambrian Research Center Field Camp for the summer of 2007. The mapping area included portions of the Ogishkemuncie Lake and Gillis Lake U.S.G.S. 7.5' Quadrangles. Mapping was performed primarily on Gabimichigami Lake,and extended north to Agamok Lake and east to Howard Lake and Peter Lake. The field area was split into two study areas: the basal contact of the Duluth Complex (Tuscarora intrusion),and the structural elements of the meta-sediments associated with the collapse of an Archaean caldera. The area was previously mapped by Gruner in 1938 in a large-scale regional mapping project of the structural geology of the Knife Lake area of north-eastern Minnesota. The purpose of this mapping was two-fold: 1) a capstone project for field camp students that provided hands on geologic experience in a serene wilderness setting, and 2) to assist in the larger goal of the state of Minnesota to remap the Boundary Waters Canoe Area.