9417768 Bethke Developing a quantitative understanding of how rapidly groundwater migrates through the subsurface in sedimentary basins is fundamental to our ability to safely dispose of toxic and radioactive wastes as well as to continued successful exploration for petroleum and metallic resources. Scientists estimate flow rates using computer models based on physical laws of flow and with geochemical methods based on the decay of radioactive or accumulation of radiogenic isotopes. Surprisingly, the two independent approaches, both seemingly correct, give broadly differing results. This study aims to reconcile these discrepancies by using quantitative methods that rigorously account for the many factors influencing the distribution of isotopes in very old groundwater within sedimentary basins
