Isotope Trace Studies of Diffusion in Silicates and of Geological Transport Processes Using Actinide Elements

Over the past year we have competed two studies of Os concentration and isotopic composition in rivers from the Himalayan uplift and in hydrothermal fluids from the Juan de Fuca Ridge. Both of these studies have been published. We have completed a study of paleo-climate in Soreq Cave, Israel, and have expanded our studies of the transport of U-Th through riverine and estuarine environments. We are completing two studies of weathering and transport in the vadose in two very different environments--one a tropical regime with a deep laterite profile and the other a northern arboreal forest with only a thin weathering zone. We have begun a new study of U-Th in aquifers with low water velocity