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Craig Johnson is a Research Geologist with the Geology, Geophysics, and Geochemistry Science Center.
Craig attended Dartmouth (AB), Michigan (MS), and Yale (PhD). He held a NASA postdoc and a staff position at the American Museum of Natural History in New York prior to joining the USGS in 1992. Craig is responsible for a stable isotope laboratory in which isotopes of carbon, hydrogen, nitrogen, oxygen, and sulfur are measured in rocks, waters, gases, and biological materials. Craig studies ore genesis, environmental impacts of mining, the source and fate of solutes in natural waters and crustal fluids, the isotopic record of marine sulfate, and isotopic records of paleoenvironments.
Exposures of sedimentary rocks in the western Brooks Range, Alaska were evaluated for their contents of metals and phosphate and for their petroleum maturation histories to determine the potential for undiscovered resources in the southern National Petroleum Reserve Alaska.
Exposures of sedimentary rocks in the western Brooks Range, Alaska were evaluated for their contents of metals and phosphate and for their petroleum maturation histories to determine the potential for undiscovered resources in the southern National Petroleum Reserve Alaska.
Exposures of sedimentary rocks in the western Brooks Range, Alaska were evaluated for their contents of metals and phosphate and for their petroleum maturation histories to determine the potential for undiscovered resources in the southern National Petroleum Reserve Alaska.
Exposures of sedimentary rocks in the western Brooks Range, Alaska were evaluated for their contents of metals and phosphate and for their petroleum maturation histories to determine the potential for undiscovered resources in the southern National Petroleum Reserve Alaska.