SUMMARY OF CHERT GRAVEL DEPOSITS IN CAVES AND THEIR POTENTIAL IN PRESERVING CULTURAL AND FAUNAL MATERIALS IN THE ARBUCKLE MOUNTAINS, SOUTHERN OKLAHOMA

The Ordovician Arbuckle Group in southern Oklahoma is host to a diversity of chert types of varying abundance within several formations. Large nodules and layers of chert erode from limestone beds on the surface and within caves, where it crumbles and becomes mobilized by fluvial processes. Due to a high density of sinkholes and ponors, much of the surface chert is carried into the subsurface where it accumulates in thick and extensive gravel beds, contributing a heterogeneous alluvium component to a dynamic triple aquifer system. The most common cryptocrystalline silicate materials within these samples include, milky quartz, smoky quartz, and flint. A few jasper and agate chalcedony were also identified. Within the karst systems, the gravel acts to filter-out larger organic materials and detritus. Where gravel accumulates in traps within phreatic loops, gravel boils develop on the downstream end and accelerate density stratification within the gravel trap. Bones of bison, broken speleothems, and a Late Archaic period style stone projectile point artifact have been recovered from smaller gravel traps and beds during dry conditions. Such items typically show little wear, suggesting the gravel helps to preserve such items when buried.