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: 200
A comparison of recharge rates in aquifers of the United States based on groundwater-age data
An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate...
Authors
P. B. McMahon, Niel Plummer, J.K. Böhlke, S.D. Shapiro, S.R. Hinkle
Erratum to: Isotopic composition and origin of indigenous natural perchlorate and co-occurring nitrate in the southwestern United States
No abstract available.
Authors
W Andrew Jackson, J.K. Böhlke, Baohua Gu, Paul B. Hatzinger, Neil C. Sturchio
Isotopic composition and origin of indigenous natural perchlorate and co-occurring nitrate in the southwestern United States
Perchlorate (ClO4−) has been detected widely in groundwater and soils of the southwestern United States. Much of this ClO4− appears to be natural, and it may have accumulated largely through wet and dry atmospheric deposition. This study evaluates the isotopic composition of natural ClO4− indigenous to the southwestern U.S. Stable isotope ratios were measured in ClO4− (δ18O, Δ17O, δ37Cl)...
Authors
W. Andrew Jackson, J.K. Böhlke, Baohua Gu, Paul B. Hatzinger, Neil C. Sturchio
Mixing effects on apparent reaction rates and isotope fractionation during denitrification in a heterogeneous aquifer
Gradients in contaminant concentrations and isotopic compositions commonly are used to derive reaction parameters for natural attenuation in aquifers. Differences between field‐scale (apparent) estimated reaction rates and isotopic fractionations and local‐scale (intrinsic) effects are poorly understood for complex natural systems. For a heterogeneous alluvial fan aquifer, numerical...
Authors
Christopher T. Green, J.K. Böhlke, Barbara A. Bekins, Steven P. Phillips
Natural chlorate in the environment: Application of a new IC-ESI/MS/MS method with a Cl18O3- internal standard
A new ion chromatography electrospray tandem mass spectrometry (IC-ESI/MS/MS) method has been developed for quantification and confirmation of chlorate (ClO3−) in environmental samples. The method involves the electro-chemical generation of isotopically labeled chlorate internal standard (Cl18O3−) using 18O water (H218O). The standard was added to all samples prior to analysis thereby...
Authors
Balaji Rao, Paul B. Hatzinger, J.K. Böhlke, Neil C. Sturchio, Brian J. Andraski, Frank D. Eckardt, W. Andrew Jackson
Comprehensive inter-laboratory calibration of reference materials for δ18O versus VSMOW using various on-line high-temperature conversion techniques
Internationally distributed organic and inorganic oxygen isotopic reference materials have been calibrated by six laboratories carrying out more than 5300 measurements using a variety of high-temperature conversion techniques (HTC) in an evaluation sponsored by the International Union of Pure and Applied Chemistry (IUPAC). To aid in the calibration of these reference materials, which...
Authors
Willi A. Brand, Tyler B. Coplen, Anita T. Aerts-Bijma, John Karl Bohlke, Matthias Gehre, Heike Geilmann, Manfred Groning, Henk G. Jansen, Harro A. J. Meijer, Stanley J. Mroczkowski, Haiping Qi, Karin Soergel, Hilary Stuart-Williams, Stephan M. Weise, Roland A. Werner
Errata: Atomic weights of the elements: Review 2000
No abstract available.
Authors
John R. de Laeter, John Karl Bohlke, P. De Bievre, H. Hidaka, H.S. Peiser, K.J.R. Rosman, P.D.P. Taylor
Multi-scale measurements and modeling of denitrification in streams with varying flow and nitrate concentration in the upper Mississippi River basin, USA
Denitrification is an important net sink for NO3− in streams, but direct measurements are limited and in situ controlling factors are not well known. We measured denitrification at multiple scales over a range of flow conditions and NO3− concentrations in streams draining agricultural land in the upper Mississippi River basin. Comparisons of reach-scale measurements (in-stream mass...
Authors
J.K. Böhlke, Ronald C. Antweiler, Judson W. Harvey, Andrew E. Laursen, Lesley K. Smith, Richard L. Smith, Mary A. Voytek
Contrasting residence times and fluxes of water and sulfate in two small forested watersheds in Virginia, USA
Watershed mass balances for solutes of atmospheric origin may be complicated by the residence times of water and solutes at various time scales. In two small forested headwater catchments in the Appalachian Mountains of Virginia, USA, mean annual export rates of SO4= differ by a factor of 2, and seasonal variations in SO4= concentrations in atmospheric deposition and stream water are out...
Authors
J.K. Böhlke, R. L. Michel
Flow and geochemistry of groundwater beneath a back-barrier lagoon: The subterranean estuary at Chincoteague Bay, Maryland, USA
To better understand large-scale interactions between fresh and saline groundwater beneath an Atlantic coastal estuary, an offshore drilling and sampling study was performed in a large barrier-bounded lagoon, Chincoteague Bay, Maryland, USA. Groundwater that was significantly fresher than overlying bay water was found in shallow plumes up to 8 m thick extending more than 1700 m offshore...
Authors
J.F. Bratton, J.K. Böhlke, D.E. Krantz, C.R. Tobias
Biogeochemistry at a wetland sediment-alluvial aquifer interface in a landfill leachate plume
The biogeochemistry at the interface between sediments in a seasonally ponded wetland (slough) and an alluvial aquifer contaminated with landfill leachate was investigated to evaluate factors that can effect natural attenuation of landfill leachate contaminants in areas of groundwater/surface-water interaction. The biogeochemistry at the wetland-alluvial aquifer interface differed...
Authors
M.M. Lorah, I.M. Cozzarelli, J.K. Böhlke
Nitrification and denitrification in a midwestern stream containing high nitrate: In situ assessment using tracers in dome-shaped incubation chambers
The extent to which in-stream processes alter or remove nutrient loads in agriculturally impacted streams is critically important to watershed function and the delivery of those loads to coastal waters. In this study, patch-scale rates of in-stream benthic processes were determined using large volume, open-bottom benthic incubation chambers in a nitrate-rich, first to third order stream...
Authors
R. L. Smith, J.K. Böhlke, D.A. Repert, C.P. Hart
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: 200
A comparison of recharge rates in aquifers of the United States based on groundwater-age data
An overview is presented of existing groundwater-age data and their implications for assessing rates and timescales of recharge in selected unconfined aquifer systems of the United States. Apparent age distributions in aquifers determined from chlorofluorocarbon, sulfur hexafluoride, tritium/helium-3, and radiocarbon measurements from 565 wells in 45 networks were used to calculate...
Authors
P. B. McMahon, Niel Plummer, J.K. Böhlke, S.D. Shapiro, S.R. Hinkle
Erratum to: Isotopic composition and origin of indigenous natural perchlorate and co-occurring nitrate in the southwestern United States
No abstract available.
Authors
W Andrew Jackson, J.K. Böhlke, Baohua Gu, Paul B. Hatzinger, Neil C. Sturchio
Isotopic composition and origin of indigenous natural perchlorate and co-occurring nitrate in the southwestern United States
Perchlorate (ClO4−) has been detected widely in groundwater and soils of the southwestern United States. Much of this ClO4− appears to be natural, and it may have accumulated largely through wet and dry atmospheric deposition. This study evaluates the isotopic composition of natural ClO4− indigenous to the southwestern U.S. Stable isotope ratios were measured in ClO4− (δ18O, Δ17O, δ37Cl)...
Authors
W. Andrew Jackson, J.K. Böhlke, Baohua Gu, Paul B. Hatzinger, Neil C. Sturchio
Mixing effects on apparent reaction rates and isotope fractionation during denitrification in a heterogeneous aquifer
Gradients in contaminant concentrations and isotopic compositions commonly are used to derive reaction parameters for natural attenuation in aquifers. Differences between field‐scale (apparent) estimated reaction rates and isotopic fractionations and local‐scale (intrinsic) effects are poorly understood for complex natural systems. For a heterogeneous alluvial fan aquifer, numerical...
Authors
Christopher T. Green, J.K. Böhlke, Barbara A. Bekins, Steven P. Phillips
Natural chlorate in the environment: Application of a new IC-ESI/MS/MS method with a Cl18O3- internal standard
A new ion chromatography electrospray tandem mass spectrometry (IC-ESI/MS/MS) method has been developed for quantification and confirmation of chlorate (ClO3−) in environmental samples. The method involves the electro-chemical generation of isotopically labeled chlorate internal standard (Cl18O3−) using 18O water (H218O). The standard was added to all samples prior to analysis thereby...
Authors
Balaji Rao, Paul B. Hatzinger, J.K. Böhlke, Neil C. Sturchio, Brian J. Andraski, Frank D. Eckardt, W. Andrew Jackson
Comprehensive inter-laboratory calibration of reference materials for δ18O versus VSMOW using various on-line high-temperature conversion techniques
Internationally distributed organic and inorganic oxygen isotopic reference materials have been calibrated by six laboratories carrying out more than 5300 measurements using a variety of high-temperature conversion techniques (HTC) in an evaluation sponsored by the International Union of Pure and Applied Chemistry (IUPAC). To aid in the calibration of these reference materials, which...
Authors
Willi A. Brand, Tyler B. Coplen, Anita T. Aerts-Bijma, John Karl Bohlke, Matthias Gehre, Heike Geilmann, Manfred Groning, Henk G. Jansen, Harro A. J. Meijer, Stanley J. Mroczkowski, Haiping Qi, Karin Soergel, Hilary Stuart-Williams, Stephan M. Weise, Roland A. Werner
Errata: Atomic weights of the elements: Review 2000
No abstract available.
Authors
John R. de Laeter, John Karl Bohlke, P. De Bievre, H. Hidaka, H.S. Peiser, K.J.R. Rosman, P.D.P. Taylor
Multi-scale measurements and modeling of denitrification in streams with varying flow and nitrate concentration in the upper Mississippi River basin, USA
Denitrification is an important net sink for NO3− in streams, but direct measurements are limited and in situ controlling factors are not well known. We measured denitrification at multiple scales over a range of flow conditions and NO3− concentrations in streams draining agricultural land in the upper Mississippi River basin. Comparisons of reach-scale measurements (in-stream mass...
Authors
J.K. Böhlke, Ronald C. Antweiler, Judson W. Harvey, Andrew E. Laursen, Lesley K. Smith, Richard L. Smith, Mary A. Voytek
Contrasting residence times and fluxes of water and sulfate in two small forested watersheds in Virginia, USA
Watershed mass balances for solutes of atmospheric origin may be complicated by the residence times of water and solutes at various time scales. In two small forested headwater catchments in the Appalachian Mountains of Virginia, USA, mean annual export rates of SO4= differ by a factor of 2, and seasonal variations in SO4= concentrations in atmospheric deposition and stream water are out...
Authors
J.K. Böhlke, R. L. Michel
Flow and geochemistry of groundwater beneath a back-barrier lagoon: The subterranean estuary at Chincoteague Bay, Maryland, USA
To better understand large-scale interactions between fresh and saline groundwater beneath an Atlantic coastal estuary, an offshore drilling and sampling study was performed in a large barrier-bounded lagoon, Chincoteague Bay, Maryland, USA. Groundwater that was significantly fresher than overlying bay water was found in shallow plumes up to 8 m thick extending more than 1700 m offshore...
Authors
J.F. Bratton, J.K. Böhlke, D.E. Krantz, C.R. Tobias
Biogeochemistry at a wetland sediment-alluvial aquifer interface in a landfill leachate plume
The biogeochemistry at the interface between sediments in a seasonally ponded wetland (slough) and an alluvial aquifer contaminated with landfill leachate was investigated to evaluate factors that can effect natural attenuation of landfill leachate contaminants in areas of groundwater/surface-water interaction. The biogeochemistry at the wetland-alluvial aquifer interface differed...
Authors
M.M. Lorah, I.M. Cozzarelli, J.K. Böhlke
Nitrification and denitrification in a midwestern stream containing high nitrate: In situ assessment using tracers in dome-shaped incubation chambers
The extent to which in-stream processes alter or remove nutrient loads in agriculturally impacted streams is critically important to watershed function and the delivery of those loads to coastal waters. In this study, patch-scale rates of in-stream benthic processes were determined using large volume, open-bottom benthic incubation chambers in a nitrate-rich, first to third order stream...
Authors
R. L. Smith, J.K. Böhlke, D.A. Repert, C.P. Hart
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.