GSA Annual Meeting in Phoenix, Arizona, USA - 2019

Paper No. 25-4
Presentation Time: 9:00 AM-5:30 PM


FISCHER, Emily L., Department of Geology and Geography, Georgia Southern University, Box 8149, Statesboro, GA 30460 and DUNDAS, Erin, Department of Geology, University of Vermont, 180 Colchester Ave., Burlington, VT 05405

In the summer of 2019, we worked as Cave Guides through the GeoCorps program in the Tongass National Forest on Prince of Wales Island, Alaska, at the El Capitan Cave. El Capitan is the largest cave in Alaska with over two miles of mapped passages; in soggy southeast Alaska, caves and other karst features develop much faster than in other parts of the world. The limestone that composes the karst system was deposited between 427 and 423 Ma and is comprised primarily of algal, coralline, and stromatolite mats, and reef and paleokarst breccia. Within the cave, there is evidence indicating that it was used by natives, and fossil discoveries have shown that mammals were using the cave much earlier. As Cave Guides, we were responsible for interpreting geological, archaeological, and biological features to the public during free daily tours. The visitors included both island residents and tourists from around the world, and many had little knowledge of geologic processes involved in the development of karst systems. As the summer progressed, we adapted better guiding approaches in order to interpret features in the cave in a way that grew public understanding and appreciation.