On Sept. 15, Dr., Ron Worl led a field trip with more than 20 participants through the geological formation of the Wind River Range. The free field trip was hosted by Sublette BOCES and covered ground between Elkhart Park and the town of Pinedale.
Fremont Lake straddles two major geologic terrains, the Precambrian crystalline rocks that make up the Wind River Range and the Paleozoic to Mesozoic sedimentary rocks that underlie the Green River Basin. The contact between the Precambrian crystalline rocks and the Paleozoic to Mesozoic sedimentary rocks is a major thrust fault dipping to the northeast that carried the crystalline rocks over the sedimentary rocks. Fremont is a glacial lake that formed during the Pinedale stage of mountain glaciation. All of the land forms that surround the lake and that extend into the basin for a considerable distance were formed during this glacial period.