Clastic Sediments in Caves – Imperfect Recorders of Processes in Karst

Abstract

Clastic sediments have played an important role in deciphering geologic history and processes since the inception of the discipline. Early studies of caves applied stratigraphic principles to karst deposits. The majority of cave deposits are breakdown and alluvium. The alluvial materials have been successfully investigated to determine ages of caves, landscape evolution, paleoenvironmental conditions, and paleobiota. Rapid stage changes and the possibility of pipe-full flow make cave deposits different than surface deposits. This and other factors present difficulties with interpreting the cave record, but extended preservation is afforded by the “roofing” of deposits. Dating by magnetism or isotopes has been successful in many locations. Caves can be expected to persist for 10 Ma in a single erosive cycle; most cave sediments should be no older than this.