"The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them" - Sir William Bragg
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Research Interests
Utilization of radioisotopes and stable isotopes to study oceanographic environmental and hydrologic processes; Global climate changes in past and present day environments; Multi-disciplinary applications of remote sensing and GIS data.
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Primer on Radiochemistry
Over the past 50 years, there has been a dramatic increase in the interest and scope of research regarding the sources and fate of anthropogenic substances and their environmental impacts. An important aspect is determining the rate at which these changes occur. One of the best methods for assessing changes over time is by direct long term monitoring. However when such information is unavailable, other methods must be employed. In sedimentary environments chronological scales, sedimentation rates, sediment dynamics, bioturbation rates and contaminant transport can be traced using naturally occurring radioactive tracers. In order to use a radioisotope as a tracer for these natural processes the following conditions must be fulfilled: (1) The chemistry of the isotope is known; (2) the initial amount of the isotope per unit of material is known or can be accurately determined i.e. its input is known; (3) The only change in concentration of the isotope in the sediments is due to radioactive, i.e. if it not mobile in sediments; and (4) it must be relatively easy to measure. The five major radioisotopes that satisfy these criteria are 137Cs, 7Be, 14C, 234Th and 210Pb. All have proven useful for measuring sediment dynamics and tracing environmental processes over weeks to thousands of years.
