Testing the effectiveness of beryllium-7 as a tracer of the movement of sediment over short periods along a cave stream in Hidden River Cave, Kentucky U.S.A.

A feasibility study using beryllium-7 (Be-7) as a tracer of the movement of sediment through a karstic basin over short timescales of 2 to 3 months was undertaken. If Be-7 is an effective tracer of sediment movement, then the average Be-7 activity measured on sediment collected from backwater facies after high-flow events would be higher than that measured after periods of low-flow conditions. To test this, sediment was collected along a cave stream in Hidden River Cave, Kentucky, U.S.A. At the most basic level, collected sediment had measureable Be-7 activities, so using Be-7 to track movement of sediment from the surface into karstic basins is a viable method. In addition, the measured Be-7 activities were higher after a period of rainfall and presumably high flow events (> 1 d m(-1) g(-1)) than after a period of relatively few rainfall events and presumably low-flow conditions (0.16 d m(-1) g(-1)).