Karl Emanuel, a geologist with the Black Hills National Forest, will discuss caves and karst systems in the Black Hills. The Black Hills is host to two of the world’s largest and most complex cave systems, as well as hundreds of less extensive, but equally complex caves and karst systems. The origin and evolution of these systems will be discussed in layman’s terms along with recent advances in cave and karst research and how that work has clarified our understanding of the size and nature of these complex and hydrologically important systems. The importance of these conduits into our regional groundwater supply will also be discussed. Homestake Adams Research and Cultural Center; 12:00 p.m.; free for members and $5 for non-members.