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
Effect of ground-water/surface-water interactions on nitrate concentrations in discharge from the South Platte River alluvial aquifer, Colorado Effect of ground-water/surface-water interactions on nitrate concentrations in discharge from the South Platte River alluvial aquifer, Colorado
Concentrations of dissolved nitrate in recharge-area water from a 200-km2 segment of the South Platte River alluvial aquifer near Greeley, Colorado, range from less than 0.1 to 58 mg/l as nitrogen, and the median concentration is 26 mg/l as nitrogen. Hydraulic-head data indicate that this nitrate-enriched ground water move toward the South Platte River. However, the median concentration...
Authors
P.B. McMahon, J.K. Böhlke
Interlaboratory comparison of reference materials for nitrogen-isotope-ratio measurements Interlaboratory comparison of reference materials for nitrogen-isotope-ratio measurements
Aliquots of seven different reference materials were distributed for an interlaboratory comparison of stable nitrogen-isotope-ratio measurements. Results from 15 laboratories were compiled and evaluated selectively to yield provisional values of 515N for each material, i, with respect to atmospheric N2 (o1SN,7air). The 515N values reported by the different laboratories are correlated in...
Authors
J.K. Bohlke, Tyler Coplen
Stable isotopes in mid-ocean ridge hydrothermal systems: Interactions between fluids, minerals, and organisms Stable isotopes in mid-ocean ridge hydrothermal systems: Interactions between fluids, minerals, and organisms
Studies of abundance variations of light stable isotopes in nature have had a tremendous impact on all aspects of geochemistry since the development, in 1947, of a gas source isotope ratio mass spectrometer capable of measuring small variations in stable isotope ratios (Nice, 1947]. Stable isotope geochemistry is now a mature field, as witnessed by the proliferation of commercially...
Authors
Wayne Shanks, J.K. Bohlke, Robert R. Seal,
Chemical analyses of ground and surface water from Battle Brook drainage basin, near Princeton, Minnesota Chemical analyses of ground and surface water from Battle Brook drainage basin, near Princeton, Minnesota
No abstract available.
Authors
R. B. Wanty, M. Tuttle, J.K. Böhlke, Paul H. Briggs
Geologic, hydrothermal, and biologic studies at Escanaba Trough, Gorda Ridge, offshore northern California Geologic, hydrothermal, and biologic studies at Escanaba Trough, Gorda Ridge, offshore northern California
No abstract available.
Authors
Robert Zierenberg, Carol Reiss
Radium isotope geochemistry of thermal waters, Yellowstone National Park, Wyoming, USA Radium isotope geochemistry of thermal waters, Yellowstone National Park, Wyoming, USA
Radium isotope activities (226Ra, 228Ra, and 224Ra), chemical compositions, and sulfur isotope ratios in sulfate were determined for water samples from thermal areas in Yellowstone National Park, Wyoming. Activities of 226Ra in these waters range from 228Ra226Ra range from 0.26 to 14.2, and those of 224Ra228Ra range from 0.73 to 3.1. Radium concentrations are inversely correlated with...
Authors
N.C. Sturchio, John K. Bohlke
Chemical, isotopic, and microbiological evidence for denitrification during transport of domestic wastewater through a thick unsaturated zone in the Mojave Desert, San Bernardino County, California Chemical, isotopic, and microbiological evidence for denitrification during transport of domestic wastewater through a thick unsaturated zone in the Mojave Desert, San Bernardino County, California
Nitrogen in downward-infiltrating wastewater discharged from seepage pits (dry wells) at residences in the upper Mojave River Basin, California represents a significant potential source of nitrate contamination to the underlying ground water. However, increases in nitrate concentration in the ground water have not yet been observed. The low nitrate concentration in the ground water may...
Authors
R. Schroeder, P. Martin, J.K. Böhlke
New reference materials for nitrogen-isotope-ratio measurements New reference materials for nitrogen-isotope-ratio measurements
Three new reference materials were manufactured for calibration of relative stable nitrogen‐isotope‐ratio measurements: USGS25 (ammonium sulfate) δ615″=−30 per mil USGS26 (ammonium sulfate) δ615″=+54 per mil USGS32 (potassium nitrate) δ615″=+180 per mil where δN′, relative to atmospheric nitrogen, is an approximate value subject to change following interlaboratory comparisons. These...
Authors
J.K. Bohlke, C. Gwinn, T. B. Coplen
Brine history indicated by argon, krypton, chlorine, bromine, and iodine analyses of fluid inclusions from the Mississippi Valley type lead-fluorite-barite deposits at Hansonburg, New Mexico Brine history indicated by argon, krypton, chlorine, bromine, and iodine analyses of fluid inclusions from the Mississippi Valley type lead-fluorite-barite deposits at Hansonburg, New Mexico
Argon, krypton, chlorine, bromine, and iodine were measured in a homogeneous population of high-salinity hydrothermal fluid inclusions from the Tertiary-age Mississippi Valley-type (MVT) lead-fluorite-barite deposits at Hansonburg, New Mexico to establish new types of evidence for the history of both the fluid and the major dissolved salts. Noble gases and halogens in fluid inclusions...
Authors
J.K. Böhlke, J.J. Irwin
Laser microprobe analyses of noble gas isotopes and halogens in fluid inclusions: Analyses of microstandards and synthetic inclusions in quartz Laser microprobe analyses of noble gas isotopes and halogens in fluid inclusions: Analyses of microstandards and synthetic inclusions in quartz
Ar, Kr, Xe, Cl, Br, I, and K abundances and isotopic compositions have been measured in microscopic fluid inclusions in minerals by noble gas mass spectrometry following neutron irradiation and laser extraction. The laser microprobe noble gas mass spectrometric (LMNGMS) technique was quantified by use of microstandards, including air-filled capillary tubes, synthetic basalt glass grains...
Authors
J.K. Böhlke, J.J. Irwin
Laser microprobe analyses of Cl, Br, I, and K in fluid inclusions: Implications for sources of salinity in some ancient hydrothermal fluids Laser microprobe analyses of Cl, Br, I, and K in fluid inclusions: Implications for sources of salinity in some ancient hydrothermal fluids
The relative concentrations of Cl, Br, I, and K in fluid inclusions in hydrothermal minerals were measured by laser microprobe noble gas mass spectrometry on irradiated samples containing 10−10 to 10−8 L of fluid. Distinctive halogen signatures indicate contrasting sources of fluid salinity in fluid inclusions from representative “magmatic” (St. Austell), “metamorphic” (Alleghany), and...
Authors
J.K. Böhlke, J.J. Irwin
By
Reporting of nitrogen-isotope abundances (Technical Report) Reporting of nitrogen-isotope abundances (Technical Report)
To eliminate possible confusion in the reporting of nitrogen-isotope analyses, the Commission on Atomic Weights and Isotopic Abundances recommends that the value 272 be employed for the 14N/15N value of N2 in air for calculating atom percent 15N from measured δ15N values.
Authors
Tyler Coplen, H.R. Krouse, J.K. Bohlke
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
Effect of ground-water/surface-water interactions on nitrate concentrations in discharge from the South Platte River alluvial aquifer, Colorado Effect of ground-water/surface-water interactions on nitrate concentrations in discharge from the South Platte River alluvial aquifer, Colorado
Concentrations of dissolved nitrate in recharge-area water from a 200-km2 segment of the South Platte River alluvial aquifer near Greeley, Colorado, range from less than 0.1 to 58 mg/l as nitrogen, and the median concentration is 26 mg/l as nitrogen. Hydraulic-head data indicate that this nitrate-enriched ground water move toward the South Platte River. However, the median concentration...
Authors
P.B. McMahon, J.K. Böhlke
Interlaboratory comparison of reference materials for nitrogen-isotope-ratio measurements Interlaboratory comparison of reference materials for nitrogen-isotope-ratio measurements
Aliquots of seven different reference materials were distributed for an interlaboratory comparison of stable nitrogen-isotope-ratio measurements. Results from 15 laboratories were compiled and evaluated selectively to yield provisional values of 515N for each material, i, with respect to atmospheric N2 (o1SN,7air). The 515N values reported by the different laboratories are correlated in...
Authors
J.K. Bohlke, Tyler Coplen
Stable isotopes in mid-ocean ridge hydrothermal systems: Interactions between fluids, minerals, and organisms Stable isotopes in mid-ocean ridge hydrothermal systems: Interactions between fluids, minerals, and organisms
Studies of abundance variations of light stable isotopes in nature have had a tremendous impact on all aspects of geochemistry since the development, in 1947, of a gas source isotope ratio mass spectrometer capable of measuring small variations in stable isotope ratios (Nice, 1947]. Stable isotope geochemistry is now a mature field, as witnessed by the proliferation of commercially...
Authors
Wayne Shanks, J.K. Bohlke, Robert R. Seal,
Chemical analyses of ground and surface water from Battle Brook drainage basin, near Princeton, Minnesota Chemical analyses of ground and surface water from Battle Brook drainage basin, near Princeton, Minnesota
No abstract available.
Authors
R. B. Wanty, M. Tuttle, J.K. Böhlke, Paul H. Briggs
Geologic, hydrothermal, and biologic studies at Escanaba Trough, Gorda Ridge, offshore northern California Geologic, hydrothermal, and biologic studies at Escanaba Trough, Gorda Ridge, offshore northern California
No abstract available.
Authors
Robert Zierenberg, Carol Reiss
Radium isotope geochemistry of thermal waters, Yellowstone National Park, Wyoming, USA Radium isotope geochemistry of thermal waters, Yellowstone National Park, Wyoming, USA
Radium isotope activities (226Ra, 228Ra, and 224Ra), chemical compositions, and sulfur isotope ratios in sulfate were determined for water samples from thermal areas in Yellowstone National Park, Wyoming. Activities of 226Ra in these waters range from 228Ra226Ra range from 0.26 to 14.2, and those of 224Ra228Ra range from 0.73 to 3.1. Radium concentrations are inversely correlated with...
Authors
N.C. Sturchio, John K. Bohlke
Chemical, isotopic, and microbiological evidence for denitrification during transport of domestic wastewater through a thick unsaturated zone in the Mojave Desert, San Bernardino County, California Chemical, isotopic, and microbiological evidence for denitrification during transport of domestic wastewater through a thick unsaturated zone in the Mojave Desert, San Bernardino County, California
Nitrogen in downward-infiltrating wastewater discharged from seepage pits (dry wells) at residences in the upper Mojave River Basin, California represents a significant potential source of nitrate contamination to the underlying ground water. However, increases in nitrate concentration in the ground water have not yet been observed. The low nitrate concentration in the ground water may...
Authors
R. Schroeder, P. Martin, J.K. Böhlke
New reference materials for nitrogen-isotope-ratio measurements New reference materials for nitrogen-isotope-ratio measurements
Three new reference materials were manufactured for calibration of relative stable nitrogen‐isotope‐ratio measurements: USGS25 (ammonium sulfate) δ615″=−30 per mil USGS26 (ammonium sulfate) δ615″=+54 per mil USGS32 (potassium nitrate) δ615″=+180 per mil where δN′, relative to atmospheric nitrogen, is an approximate value subject to change following interlaboratory comparisons. These...
Authors
J.K. Bohlke, C. Gwinn, T. B. Coplen
Brine history indicated by argon, krypton, chlorine, bromine, and iodine analyses of fluid inclusions from the Mississippi Valley type lead-fluorite-barite deposits at Hansonburg, New Mexico Brine history indicated by argon, krypton, chlorine, bromine, and iodine analyses of fluid inclusions from the Mississippi Valley type lead-fluorite-barite deposits at Hansonburg, New Mexico
Argon, krypton, chlorine, bromine, and iodine were measured in a homogeneous population of high-salinity hydrothermal fluid inclusions from the Tertiary-age Mississippi Valley-type (MVT) lead-fluorite-barite deposits at Hansonburg, New Mexico to establish new types of evidence for the history of both the fluid and the major dissolved salts. Noble gases and halogens in fluid inclusions...
Authors
J.K. Böhlke, J.J. Irwin
Laser microprobe analyses of noble gas isotopes and halogens in fluid inclusions: Analyses of microstandards and synthetic inclusions in quartz Laser microprobe analyses of noble gas isotopes and halogens in fluid inclusions: Analyses of microstandards and synthetic inclusions in quartz
Ar, Kr, Xe, Cl, Br, I, and K abundances and isotopic compositions have been measured in microscopic fluid inclusions in minerals by noble gas mass spectrometry following neutron irradiation and laser extraction. The laser microprobe noble gas mass spectrometric (LMNGMS) technique was quantified by use of microstandards, including air-filled capillary tubes, synthetic basalt glass grains...
Authors
J.K. Böhlke, J.J. Irwin
Laser microprobe analyses of Cl, Br, I, and K in fluid inclusions: Implications for sources of salinity in some ancient hydrothermal fluids Laser microprobe analyses of Cl, Br, I, and K in fluid inclusions: Implications for sources of salinity in some ancient hydrothermal fluids
The relative concentrations of Cl, Br, I, and K in fluid inclusions in hydrothermal minerals were measured by laser microprobe noble gas mass spectrometry on irradiated samples containing 10−10 to 10−8 L of fluid. Distinctive halogen signatures indicate contrasting sources of fluid salinity in fluid inclusions from representative “magmatic” (St. Austell), “metamorphic” (Alleghany), and...
Authors
J.K. Böhlke, J.J. Irwin
By
Reporting of nitrogen-isotope abundances (Technical Report) Reporting of nitrogen-isotope abundances (Technical Report)
To eliminate possible confusion in the reporting of nitrogen-isotope analyses, the Commission on Atomic Weights and Isotopic Abundances recommends that the value 272 be employed for the 14N/15N value of N2 in air for calculating atom percent 15N from measured δ15N values.
Authors
Tyler Coplen, H.R. Krouse, J.K. Bohlke
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.