Book Description

This study investigated the depositional patterns of clastic cave sediments in four caves in Greenbrier and Monroe Counties of West Virginia to test whether deposits found in a single karst conduit are representative of regional paleoenvironmental conditions. If no other variables obscure such signals, conduits that were hydrologically active during the same time should retain similar sedimentary records, documenting terrestrial paleoenvironmental conditions. While numerous sediment studies have been conducted in caves, no study has verified or challenged the assumption that sediments accurately record previous environmental conditions for a given region. Caves were selected on the basis of proximity to each other, similar geology, presence of discrete input to long conduits, and apparently similar ages. Within the cave systems there is limited stacking of passages, reducing the complexity of sediment deposition. Stratigraphic columns were constructed in the field and samples were collected for sediment (grain size, lithology), environmental magnetic (magnetic susceptibility, frequency dependence, anhysteretic remnant magnetization, isothermal remnant magnetization), and paleomagnetic analyses. Due to erosion and depositional complexities, it was a challenge to find complete sedimentary sections. Sediment analyses indicated that samples ranged in size from clay to cobbles and many samples analyzed for paleomagnetism showed normal polarity. Taken in context with the landscape, this suggests that the conduits have been active for less than ~1Ma. Catchment areas were underfit to conduit dimensions, which was expected as surface drainages evolve and become pirated to other conduits. Some samples analyzed for environmental magnetic parameters contained high magnetic concentrations, large amounts of superparamagnetic grains, and an abundance of a low-coercivity magnetic mineral, possible maghemite. Therefore, cave sediment samples with a similar magnetic signature are inferred to correspond to warmer periods of increased pedogenesis and the mechanical transport of soils into the caves. Although it was not possible to associate sediments with specific interglacial time periods, lithostratigraphic correlations could still be established. Through the use of lithostratigraphy, it was possible to form intra-cave and inter-cave correlations.