Hand specimens of rocks collected in and around Marathon County as part of a bedrock mapping project in the 1970s and 1980s. Specimens were collected by P.E. Myers and UW-Oshkosh geologist Gene LaBerge as part of the field work supporting WGNHS publication Information Circular 45: Precambrian Geology of Marathon County, 1983. The collection consists of about 1500 specimens taken from approximately 580 outcrop locations.
