Bedrock Geologic Map of a Portion of the South Kawishawi Intrusion, Lake County, Minnesota

Abstract

This map is the result of a six day mapping project in the South Kawishiwi Intrusion, which took place from August 3rd through the 8th of 2014. This map was created on a 1:5000 scale by Precambrian Research Center field camp students at the University of Minnesota Duluth under the supervision of Dr. Dean Peterson. Data for this project was compiled from Peterson (2014) and Phinney (1966) and combined with the data that was collected over the mapping period. The purpose of this project was to create a more detailed and accurate geological map of this locality on the Duluth Complex, as well as a better understanding of possible glacial till deposits in the area. This project was also performed to test the conceptual model of this location, which inferred that the lineaments seen on LIDAR of the area consisted of mainly fault-like features and that the area was primarily covered by glacial water table through these fractures/faults due to mining operations and tailings processes. This capstone area was selected under the idea that the proposed conceptual model for the lineaments in the mapping area were incorrect. After six days of mapping and data collection on this location it is accurate to conclude that this area consists of almost entirely bedrock composed of large amounts of varying types of troctolite and anorthosite, with a sparse amount of localized till piles that consist of small pebbles to large boulders. The 1227 outcrops that were mapped in this area were not found to be fractured/faulted but instead broke apart due to frost wedging. This is the dominant type of mechanical weathering in the area. of this area was found to be false and the local water table and aquifers in this area would not be in jeapordy by consequence of mining operations.