The Relationship Between the Mineral Composition of Speleothems and Mineralization of Breccia Pipes: Evidence from Corkscrew Cave, Arizona, Usa

Solution-collapse breccia pipes are common features in northwestern Arizona. They were mineralized with uranium, but associated with it are a suite of elements (e.g., As, Mo, V, Ba, Cu, Pb, and Fe) that may form other ore minerals. Breccia bodies are in some cases cut by cave passages, such as at Corkscrew Cave, Arizona, where such structures are exposed along the walls and on the cave ceilings. The abundance of gypsum and barite throughout the cave and their isotopically light δ34S value (−11 to −7‰) suggest deposition from warm sulfidic solutions that were also responsible, at least in part, for development of the recent cave passages that dissect older paleokarst breccia bodies. The presence of calcite showing depleted δ18O values (−11.3 and −16.9‰) is considered indicative of a low-temperature hydrothermal episode in the deposition history of cave minerals. Groundwater percolating through the breccia-pipe bodies mobilized and transported ore-related ions into the cave, where they formed a unique assemblage of minerals (i.e., hörnesite, talmessite, carnotite, tyuyamunite, claudetite, and powellite) that mirror breccia-pipe mineralization