John Karl Bohlke, PhD
Dr. John Karl Bohlke is a Scientist Emeritus affiliated with the Earth Systems Processes Division and the Reston Stable Isotope Laboratory of the USGS Water Resources Mission Area.
Dr. John Karl (JK) Bohlke retired as a Senior Research Scientist and currently serves as a Scientist Emeritus affiliated with the Earth System Processes Division and the Reston Stable Isotope Laboratory of the Water Mission Area. During his career with USGS, he has studied processes related to both mineral resources and water resources. His published work includes field and laboratory-based studies of water-rock interactions, geochronology, and chemical transport in diverse hydrogeologic settings. Recent activities include development of stable isotopic methods and applications in hydrology and biogeochemistry, use of isotopes and environmental tracers to determine transport and reaction rates in groundwater and surface water, and multidisciplinary investigations of contaminant origin and migration. Selected priority topics related to water quality include excess nutrients and inorganic contaminants, effects of agriculture and wastewater disposal practices, watershed responses to land use change, groundwater/surface water interactions, and environmental forensics.
Professional Experience
Hydrologist, National Research Program and Earth System Processes Division, Water Mission Area, US Geological Survey, Reston, Virginia (since 1991)
Geologist, Eastern Mineral Resources, US Geological Survey, Reston, Virginia
Postdoc (Geoscience), Argonne National Laboratory, Chicago, Illinois
Geologist, Western Mineral Resources, US Geological Survey, Menlo Park, California
Cartographer, US Soil Conservation Service, Hyattsville, Maryland
Education and Certifications
PhD (Geology and Geophysics), University of California, Berkeley, California
MS (Marine Geology), Rosenstiel School of Marine and Atmospheric Sciences, University of Miami, Florida
BS (Geology), University of Michigan, Ann Arbor, Michigan
Science and Products
Filter Total Items: 201
Microanalysis of trace elements and noble gas isotopes in minerals and fluid inclusions Microanalysis of trace elements and noble gas isotopes in minerals and fluid inclusions
No abstract available.
Authors
J.J. Irwin, J.K. Bohlke
Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines
Methane-hydrogen gas seeps with mantle-like C and noble gas isotopic characteristics issue from partially serpentinized ultramafic rocks in the Zambales ophiolite, Philippines. New measurements of noble gas and 14C isotope abundances, rock/mixed-volatile equilibrium calculations, and previous chemical and isotopic data suggest that these reduced gases are products of periodotite...
Authors
T.A. Abrajano, N.C. Sturchio, B. Kennedy, G.L. Lyon, K. Muehlenbachs, J.K. Böhlke
Comparison of metasomatic reactions between a common CO2-rich vein fluid and diverse wall rocks: Intensive variables, mass transfers, and Au mineralization at Alleghany, California Comparison of metasomatic reactions between a common CO2-rich vein fluid and diverse wall rocks: Intensive variables, mass transfers, and Au mineralization at Alleghany, California
The gold deposits at Alleghany, California, are typical of many epigenetic gold-bearing hydrothermal vein systems in metamorphic terranes worldwide. Detailed analyses of alteration halos in serpentinite, mafic amphibolite, and granite wall rocks at Alleghany indicate that widely contrasting deposit types, ranging from fuchsite-carbonate schists to pyrite-albitites, resulted when...
Authors
J.K. Böhlke
Stable isotope investigation of gold quartz veins at the Oriental mine, Alleghany District, California Stable isotope investigation of gold quartz veins at the Oriental mine, Alleghany District, California
No abstract available.
Authors
J.K. Böhlke, R.M. Coveney, R. Rye, Ivan Barnes
Rb-Sr, K-Ar, and stable isotope evidence for the ages and sources of fluid components of gold-bearing quartz veins in the northern Sierra Nevada foothills metamorphic belt, California Rb-Sr, K-Ar, and stable isotope evidence for the ages and sources of fluid components of gold-bearing quartz veins in the northern Sierra Nevada foothills metamorphic belt, California
Gold-bearing quartz veins occur in and near major fault zones in deformed oceanic and island-arc rocks west of the main outcrop of the Sierra Nevada composite batholith. Veins typically occupy minor reverse faults that crosscut blueschist to amphibolite-grade metamorphic rocks whose metamorphic ages range from early Paleozoic to Jurassic. Vein micas and carbonate-quartz-mica assemblages...
Authors
J.K. Bohlke, R. Kistler
K-Ar ages relating to metamorphism, plutonism, and gold quartz vein mineralization near Alleghany, Sierra County, California K-Ar ages relating to metamorphism, plutonism, and gold quartz vein mineralization near Alleghany, Sierra County, California
No abstract available.
Authors
J.K. Bohlke, E.H. McKee
Characteristics of mineral deposit occurrences Characteristics of mineral deposit occurrences
No abstract available.
Authors
Ralph Erickson
Spectroscopic geochemical study of vanadiferous marine sediments of the Gibellini claims, southern Fish Creek Range, Eureka County, Nevada Spectroscopic geochemical study of vanadiferous marine sediments of the Gibellini claims, southern Fish Creek Range, Eureka County, Nevada
Samples of cuttings from three drill holes in the Gibellini claims were analyzed by emission spectroscopic techniques for a large suite of major and trace elements. Unoxidized siliceous "black shale" from drill hole NGA 7 is strongly enriched in Cd, Mo, Sb, Se, V, and Zn, and also contains relatively high concentrations of As, Ba, Cu, Ni, and Tl compared with nonmetalliferous shales...
Authors
J.K. Böhlke, A. Radtke, Chris Heropoulos, P. Lamothe
Non-USGS Publications**
Sturchio, N.C., Böhlke, J.K., and Binz, C.M., 1989, Radium-thorium disequilibrium and zeolite-water ion exchange in a Yellowstone hydrothermal environment. Geochimica et Cosmochimica Acta, v. 53, p. 1025-1034, https://doi.org/10.1016/0016-7037(89)90207-X.
Abrajano, T.A., Bates, J.K., and Böhlke, J.K., 1988, Linear free energy relationships in glass corrosion. Materials Issues in Art and Archeaology, Materials Research Society Proceedings, v. 125, p. 383-392, https://www.osti.gov/biblio/7179346/.
Abrajano, T.A., Sturchio, N.C., Böhlke, J.K., Poreda, R.J., Lyon, G.L., and Stevens, C.M., 1988, Methane-hydrogen gas seeps, Zambales, Philippines: Deep or shallow origin. Chemical Geology, v. 71, p. 211-222, https://doi.org/10.1016/0009-2541(88)90116-7.
Böhlke, 1988, Carbonate-sulfide equilibria and "stratabound" disseminated epigenetic gold mineralization: A proposal based on examples from Alleghany, California. Applied Geochemistry, v. 3, p. 499-516, https://doi.org/10.1016/0883-2927(88)90022-4.
Böhlke, J.K., Alt, J.C., and Muehlenbachs, K., 1984, Oxygen isotope-water relations in altered deep-sea basalts: Low temperature mineralogic controls. Canadian Journal of Earth Sciences, v. 21, p. 67-77, https://doi.org/10.1139/e84-008.
Böhlke, J.K., Honnorez, J., Honnorez-Guerstein, B.M., Muehlenbachs, K., and Petersen, N., 1981, Heterogeneous alteration of the upper oceanic crust: Correlation of rock chemistry, magnetic properties, and O-isotope ratios with alteration patterns in basalts from Site 396B, DSDP. Journal of Geophysical Research, Solid Earth, v. 86, p. 7935-7950, https://doi.org/10.1029/JB086iB09p07935.
Böhlke, J.K., Honnorez, J., and Honnorez-Guerstein, B.-M., 1980, Alteration of basalts from Site 396B, Deep Sea Drilling Project, petrographic and mineralogic studies. Contributions to Mineralogy and Petrology, v. 73, p. 341-364, https://doi.org/10.1007/BF00376628.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 201
Microanalysis of trace elements and noble gas isotopes in minerals and fluid inclusions Microanalysis of trace elements and noble gas isotopes in minerals and fluid inclusions
No abstract available.
Authors
J.J. Irwin, J.K. Bohlke
Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines Geochemistry of reduced gas related to serpentinization of the Zambales ophiolite, Philippines
Methane-hydrogen gas seeps with mantle-like C and noble gas isotopic characteristics issue from partially serpentinized ultramafic rocks in the Zambales ophiolite, Philippines. New measurements of noble gas and 14C isotope abundances, rock/mixed-volatile equilibrium calculations, and previous chemical and isotopic data suggest that these reduced gases are products of periodotite...
Authors
T.A. Abrajano, N.C. Sturchio, B. Kennedy, G.L. Lyon, K. Muehlenbachs, J.K. Böhlke
Comparison of metasomatic reactions between a common CO2-rich vein fluid and diverse wall rocks: Intensive variables, mass transfers, and Au mineralization at Alleghany, California Comparison of metasomatic reactions between a common CO2-rich vein fluid and diverse wall rocks: Intensive variables, mass transfers, and Au mineralization at Alleghany, California
The gold deposits at Alleghany, California, are typical of many epigenetic gold-bearing hydrothermal vein systems in metamorphic terranes worldwide. Detailed analyses of alteration halos in serpentinite, mafic amphibolite, and granite wall rocks at Alleghany indicate that widely contrasting deposit types, ranging from fuchsite-carbonate schists to pyrite-albitites, resulted when...
Authors
J.K. Böhlke
Stable isotope investigation of gold quartz veins at the Oriental mine, Alleghany District, California Stable isotope investigation of gold quartz veins at the Oriental mine, Alleghany District, California
No abstract available.
Authors
J.K. Böhlke, R.M. Coveney, R. Rye, Ivan Barnes
Rb-Sr, K-Ar, and stable isotope evidence for the ages and sources of fluid components of gold-bearing quartz veins in the northern Sierra Nevada foothills metamorphic belt, California Rb-Sr, K-Ar, and stable isotope evidence for the ages and sources of fluid components of gold-bearing quartz veins in the northern Sierra Nevada foothills metamorphic belt, California
Gold-bearing quartz veins occur in and near major fault zones in deformed oceanic and island-arc rocks west of the main outcrop of the Sierra Nevada composite batholith. Veins typically occupy minor reverse faults that crosscut blueschist to amphibolite-grade metamorphic rocks whose metamorphic ages range from early Paleozoic to Jurassic. Vein micas and carbonate-quartz-mica assemblages...
Authors
J.K. Bohlke, R. Kistler
K-Ar ages relating to metamorphism, plutonism, and gold quartz vein mineralization near Alleghany, Sierra County, California K-Ar ages relating to metamorphism, plutonism, and gold quartz vein mineralization near Alleghany, Sierra County, California
No abstract available.
Authors
J.K. Bohlke, E.H. McKee
Characteristics of mineral deposit occurrences Characteristics of mineral deposit occurrences
No abstract available.
Authors
Ralph Erickson
Spectroscopic geochemical study of vanadiferous marine sediments of the Gibellini claims, southern Fish Creek Range, Eureka County, Nevada Spectroscopic geochemical study of vanadiferous marine sediments of the Gibellini claims, southern Fish Creek Range, Eureka County, Nevada
Samples of cuttings from three drill holes in the Gibellini claims were analyzed by emission spectroscopic techniques for a large suite of major and trace elements. Unoxidized siliceous "black shale" from drill hole NGA 7 is strongly enriched in Cd, Mo, Sb, Se, V, and Zn, and also contains relatively high concentrations of As, Ba, Cu, Ni, and Tl compared with nonmetalliferous shales...
Authors
J.K. Böhlke, A. Radtke, Chris Heropoulos, P. Lamothe
Non-USGS Publications**
Sturchio, N.C., Böhlke, J.K., and Binz, C.M., 1989, Radium-thorium disequilibrium and zeolite-water ion exchange in a Yellowstone hydrothermal environment. Geochimica et Cosmochimica Acta, v. 53, p. 1025-1034, https://doi.org/10.1016/0016-7037(89)90207-X.
Abrajano, T.A., Bates, J.K., and Böhlke, J.K., 1988, Linear free energy relationships in glass corrosion. Materials Issues in Art and Archeaology, Materials Research Society Proceedings, v. 125, p. 383-392, https://www.osti.gov/biblio/7179346/.
Abrajano, T.A., Sturchio, N.C., Böhlke, J.K., Poreda, R.J., Lyon, G.L., and Stevens, C.M., 1988, Methane-hydrogen gas seeps, Zambales, Philippines: Deep or shallow origin. Chemical Geology, v. 71, p. 211-222, https://doi.org/10.1016/0009-2541(88)90116-7.
Böhlke, 1988, Carbonate-sulfide equilibria and "stratabound" disseminated epigenetic gold mineralization: A proposal based on examples from Alleghany, California. Applied Geochemistry, v. 3, p. 499-516, https://doi.org/10.1016/0883-2927(88)90022-4.
Böhlke, J.K., Alt, J.C., and Muehlenbachs, K., 1984, Oxygen isotope-water relations in altered deep-sea basalts: Low temperature mineralogic controls. Canadian Journal of Earth Sciences, v. 21, p. 67-77, https://doi.org/10.1139/e84-008.
Böhlke, J.K., Honnorez, J., Honnorez-Guerstein, B.M., Muehlenbachs, K., and Petersen, N., 1981, Heterogeneous alteration of the upper oceanic crust: Correlation of rock chemistry, magnetic properties, and O-isotope ratios with alteration patterns in basalts from Site 396B, DSDP. Journal of Geophysical Research, Solid Earth, v. 86, p. 7935-7950, https://doi.org/10.1029/JB086iB09p07935.
Böhlke, J.K., Honnorez, J., and Honnorez-Guerstein, B.-M., 1980, Alteration of basalts from Site 396B, Deep Sea Drilling Project, petrographic and mineralogic studies. Contributions to Mineralogy and Petrology, v. 73, p. 341-364, https://doi.org/10.1007/BF00376628.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.