James Gleason's research at the University of Michigan has emphasized the application of radiogenic isotope tracers to problems in marine geology and paleoceanography. Areas of interest include geochemical and isotopic studies of the sedimentary system, with emphasis on weathering rates, chemical cycling, chemostratigraphy, atmospheric inputs, basin analysis and continental drainage, paleogeography and paleoclimate, marine hydrothermal activity, ocean circulation and paleoceanography, and polar oceans; meteoritics, planetary geology, cosmochemistry, crustal evolution and the early Earth, hydrothermal mineral deposits; mercury and calcium isotopes as environmental tracers.