GSA Connects 2022 meeting in Denver, Colorado

Paper No. 62-8
Presentation Time: 2:00 PM-6:00 PM

IDENTIFYING SEDIMENT SOURCE AREA WITHIN A SUBSET OF THE BINKLEY CAVE SYSTEM


FLESZEWSKI, Grace, Valparaiso University, Valparaiso, IN 46383

As water enters the Binkley Cave System, a 45+ mile long sub terrain biological hotspot, it deposits sediment. The Mini Mountain room in the vadose zone of the Binkley cave system, at over 85 ft tall, is an anomaly because the breakdown in this room is coated in sediment. This sediment was thought to enter the Mini Mountain room in one of two ways, either through flood events from the adjacent river or from an overhead phreatic tube. On the surface, distinctive land use classes produce varying levels of soil erosion, and through sediment analysis it is possible to locate point source areas. Preliminary soil analysis has included particle-size analysis, magnetic susceptibility, x-ray fluorescence. Current results show that there is a significant difference between the average concentration of iron from samples from the phreatic tube and the riverbank, but that there is not a significant difference in the iron concentrations between the river bank and the mountain sediments. Ultimately this predicts that the adjacent river is acting as the sediment source for this room.