The U.S. Geological Survey
United States Virgin Islands
Joseph Colgan, Research Geologist Geosciences and Environmental Change Science Center, study magmatism and deformation of the earth’s crust, and how these processes influence the formation and distribution of natural resources and geologic hazards. This work involves geologic mapping at different scales, interpretation of subsurface and geophysical data, and laboratory analyses to determine the age and composition of rocks and minerals.
geologic mapping structural geology geochronology hermochronology geochemistry
Watts, K.E., John, D.A., Colgan, J.P., Henry, C.D., Bindeman, I.N., and Schmitt, A.K., 2016, Probing the volcanic–plutonic connection and the genesis of crystal-rich rhyolite in a deeply dissected supervolcano in the Nevada Great Basin: Source of the late Eocene Caetano Tuff: Journal of Petrology, v. 57(8), p. 1599–1644,
Curry, M.A.E., Barnes, J.B., and Colgan, J.P., 2016, Testing fault growth models with low-temperature thermochronology in the northwest Basin and Range, USA: Tectonics, v. 35,
Colgan, J.P., and Henry, C.D., 2017, Eruptive history, geochronology, and post-eruption structural evolution of the late Eocene Hall Creek Caldera, Toiyabe Range, Nevada: U.S. Geological Survey Professional Paper 1832,