Jennifer C Mcintosh

Interests

No activities entered.

Courses

Scholarly Contributions

Chapters

• Martini, A. M., Osborn, S. G., & Mcintosh, J. C. (2020). Methane in Groundwater: Understanding the Pathways. In Encyclopedia of Water: Science, Technology, and Society. Hoboken, New Jersey: John Wiley & Sons, Inc.

Journals/Publications

• Marza, M., Ferguson, G., Thorson, J., Barton, I., Kim, J., Ma, L., & McIntosh, J. (2024). Geological controls on lithium production from basinal brines across North America. Journal of Geochemical Exploration, 257, 107383.
• Person, M., McIntosh, J. C., Kim, J., Noyes, C., Bailey, L., Lingrey, S., Krantz, R., Lucero, D., Reiners, P. W., & Ferguson, G. (2024). Hydrologic windows into the crystalline basement and their controls on groundwater flow patterns across the Paradox Basin, western USA. Geological Society of America Bulletin.
• Ferguson, G., Mcintosh, J. C., Jasechko, S., Kim, J., Famiglietti, J., & McDonnell, J. (2023). Groundwater deeper than 500 m contributes less than 0.1% of global river discharge. Nature Communications Earth and Environment, 4(48). doi:10.1038/s43247-023-00697-6
• Ferguson, G., Mcintosh, J. C., Warr, O., & Sherwood Lollar, B. (2023). The low permeability of the earth's Precambrian crust. Nature Communications - Earth and Environment, 4(323). doi:10.1038/s43247-023-00968-2
• Kanduc, T., Gersi, M., Gerslova, E., & Mcintosh, J. C. (2023). Temporal and seasonal variations of silicate Svratka River and sediment characterization, Czech Republic: Geochemical and Stable Isotopic Approach. Aquatic Geochemistry. doi:10.1007/s10498-023-09414-3
• Kim, J., Martini, A. M., Ono, S., Lalk, E., Ferguson, G., & McIntosh, J. C. (2023). Clumped and conventional isotopes of natural gas reveal basin burial, denudation, and biodegradation history. Geochimica et Cosmochimica Acta, 361, 133-151.
• Mcintosh, J. C., Kim, J., Bailey, L., Osburn, M., Drake, H., Martini, A., Reiners, P. W., Stevenson, B., & Ferguson, G. (2022). Burial and denudation alter microbial life at the bottom of the kilometers-deep Critical Zone. Geochemistry, Geophysics, Geosystems, 24(e2022GC010831). doi:10.1029/2022GC010831
• Ng, J., Tyne, R., Seltzer, A., Noyes, C., McIntosh, J., & Severinghaus, J. (2023). A new large volume equilibration method for high precision measurements of dissolved noble gas stable isotopes. Rapid Communications in Mass Spectrometry, e9471.
• Kim, J., Bailey, L., Noyes, C., Tyne, R. L., Ballentine, C. J., Person, M., Ma, L., Barton, M. D., Barton, I. F., Reiners, P. W., Ferguson, G., & Mcintosh, J. C. (2022). Hydrogeochemical evolution of formation waters responsible for sandstone bleaching and ore mineralization in the Paradox Basin, Colorado Plateau, USA. Geological Society of America Bulletin. doi:https://doi.org/10.1130/B36078.1
• Kim, J., Ferguson, G., Person, M., Jiang, W., Lu, Z., Ritterbusch, F., Yang, G., Tyne, R., Bailey, L., Ballentine, C., Reiners, P. W., & Mcintosh, J. C. (2022). Krypton-81 dating constrains timing of deep groundwater flow activation. Geophysical Research Letters, 49(11), e2021GL097618.
• Marza, M., Mowat, A., Jellicoe, K., Ferguson, G., & McIntosh, J. (2022). Evaluation of strontium isotope tracers of produced water sources from multiple stacked reservoirs in Appalachian, Williston and Permian basins. Journal of Geochemical Exploration, 232, 106887.
• Mcintosh, J. C., Barnhart, E., Ruppert, L., Hiebert, R., Smith, H., Schweitzer, H., Clark, A., Weeks, E., Orem, W., Varonka, M., Platt, G., Shelton, J., Davis, K., Hyatt, R., McIntosh, J., Ashley, K., Ono, S., Martini, A., Hackley, K., , Gerlach, R., et al. (2022). In Situ Enhancement and Isotopic Labeling of Biogenic Coalbed Methane. ES&T.
• Tyne, R. L., Barry, P. H., Cheng, A., Hillegonds, D. J., Kim, J., McIntosh, J. C., & Ballentine, C. J. (2022). Basin architecture controls on the chemical evolution and 4He distribution of groundwater in the Paradox Basin. Earth and Planetary Science Letters, 589, 117580.
• Ashley, K., Davis, K. J., Martini, A., Vinson, D. S., Gerlach, R., Fields, M. W., & McIntosh, J. (2021). Deuterium as a quantitative tracer of enhanced microbial methane production. Fuel, 289, 119959.
• Cáñez, T. T., Guo, B., McIntosh, J. C., & Brusseau, M. L. (2021). Perfluoroalkyl and polyfluoroalkyl substances (PFAS) in groundwater at a reclaimed water recharge facility. Science of The Total Environment, 791, 147906.
• Ferguson, G., McIntosh, J. C., Warr, O., Sherwood, L. B., Ballentine, C. J., Famiglietti, J. S., Kim, J., Michalski, J. R., Mustard, J. F., Tarnas, J., & McDonnell, J. J. (2021). Crustal Groundwater Volumes Greater Than Previously Thought. Geophysical Research Letters, 48(16), e2021GL093549.
• Jellicoe, K., McIntosh, J. C., & Ferguson, G. (2021). Changes in Deep Groundwater Flow Patterns Related to Oil and Gas Activities. Groundwater, n/a(n/a).
• Markovich, K. H., Condon, L. E., Carroll, K. C., Purtschert, R., & McIntosh, J. C. (2021). A Mountain-Front Recharge Component Characterization Approach Combining Groundwater Age Distributions, Noble Gas Thermometry, and Fluid and Energy Transport Modeling. Water Resources Research, 57(1), e2020WR027743.
• McIntosh, J. C., & Ferguson, G. (2021). Deep Meteoric Water Circulation in Earth's Crust. Geophysical Research Letters, 48(5), e2020GL090461.
• Moravec, B. G., Keifer, V., Root, R. A., White, A. M., Wang, Y., Olshansky, Y., McIntosh, J., & Chorover, J. (2021). Experimental weathering of a volcaniclastic critical zone profile: Key role of colloidal constituents in aqueous geochemical response. Chemical Geology, 559, 119886.
• Mowat, A. C., Francis, D. J., McIntosh, J. C., Lindsay, M., & Ferguson, G. (2021). Variability in Timing and Transport of Pleistocene Meltwater Recharge to Regional Aquifers. Geophysical Research Letters, 48(20), e2021GL094285.
• Noyes, C., Kim, J., Person, M., Ma, L., Ferguson, G., & McIntosh, J. C. (2021). A geochemical and isotopic assessment of hydraulic connectivity of a stacked aquifer system in the Lisbon Valley, Utah (USA), and critical evaluation of environmental tracers. Hydrogeology Journal, 29(5), 1905-1923.
• Perra, C., McIntosh, J. C., Watson, T., & Ferguson, G. (2021). Commingled Fluids in Abandoned Boreholes: Proximity Analysis of a Hidden Liability. Groundwater, n/a(n/a).
• White, A., Ma, L., Moravec, B., Chorover, J., & McIntosh, J. (2021). U-series and Sr isotopes as tracers of mineral weathering and water routing from the deep Critical Zone to streamflow in a high-elevation volcanic catchment. Chemical Geology, 570, 120156.
• Wlostowski, A. N., Molotch, N., Anderson, S. P., Brantley, S. L., Chorover, J., Dralle, D., Kumar, P., Li, L., Lohse, K. A., Mallard, J. M., McIntosh, J. C., Murphy, S. F., Parrish, E., Safeeq, M., Seyfried, M., Shi, Y., & Harman, C. (2021). Signatures of Hydrologic Function Across the Critical Zone Observatory Network. Water Resources Research, 57(3), e2019WR026635.
• Zamora, H. A., Eastoe, C. J., McIntosh, J. C., & Flessa, K. W. (2021). Groundwater Origin and Dynamics on the Eastern Flank of the Colorado River Delta, Mexico. Water, 8(2).
• Chorover, J. D., Aronson, E., Mcintosh, J. C., & Roden, E. (2020). Profiling life and its role in sculpting the Critical Zone. EOS, 101(10), 30-34.
• Condon, L. E., Markovich, K. H., Kelleher, C. A., McDonnell, J. J., Ferguson, G., & McIntosh, J. C. (2020). Where Is the Bottom of a Watershed?. Water Resources Research, 56(3), e2019WR026010.
• Dwivedi, R., Eastoe, C., Knowles, J. F., Wright, W. E., Hamann, L., Minor, R., Mitra, B., Meixner, T., McIntosh, J., Ty, F., Castro, C., Niu, G., Barron-Gafford, G. A., Abramson, N., Papuga, S. A., Stanley, M., Hu, J., & Chorover, J. (2020). Vegetation source water identification using isotopic and hydrometric observations from a subhumid mountain catchment. Ecohydrology, 13(1), e2167.
• Dwivedi, R., Knowles, J. F., Eastoe, C., Minor, R., Abramson, N., Mitra, B., Wright, W. E., McIntosh, J., Meixner, T., âTyâ, F., Castro, C., Niu, G., Barron-Gafford, G. A., Stanley, M., & Chorover, J. (2020). Ubiquitous Fractal Scaling and Filtering Behavior of Hydrologic Fluxes and Storages from A Mountain Headwater Catchment. Water, 12(2).
• Ferguson, G., Cuthbert, M. O., Befus, K., Gleeson, T., & McIntosh, J. C. (2020). Rethinking groundwater age. Nature Geoscience, 13(9), 592-594.
• Moravec, B., White, A., Root, R., Sanchez, A., Paras, B., Carr, B., Mcintosh, J. C., Pelletier, J. D., Rasmussen, C., Holbrook, W. S., & Chorover, J. D. (2020). Resolving deep critical zone architecture in complex volcanic terrain. Journal of Geophysical Research-Earth Surface. doi:10.1029/2019JF005189
• Zamora, H. A., Eastoe, C. J., Wilder, B. T., McIntosh, J. C., Meixner, T., & Flessa, K. W. (2020). Groundwater Isotopes in the Sonoyta River Watershed, USA-Mexico: Implications for Recharge Sources and Management of the Quitobaquito Springs.
• Zamora, H. A., Eastoe, C. J., Wilder, B. T., McIntosh, J. C., Meixner, T., & Flessa, K. W. (2020). Groundwater Isotopes in the Sonoyta River Watershed, USA-Mexico: Implications for Recharge Sources and Management of the Quitobaquito Springs. Water, 12(12), 3307-3307.
• Dwivedi, R., Meixner, T., Mcintosh, J. C., Ferre, P. A., Eastoe, C. J., Niu, G., Minor, R. L., Barron-Gafford, G. A., & Chorover, J. D. (2019). Hydrologic functioning of the deep Critical Zone and contributions to streamflow in a high elevation catchment: testing of multiple conceptual models. Hydrological Processes. doi:10.1002/hyp.13363
• Ferguson, G., & McIntosh, J. C. (2019). Comment on “Groundwater Pumping Is a Significant Unrecognized Contributor to Global Anthropogenic Element Cycles”. Groundwater, 57(1), 82-82.
• Kanduč, T., Å lejkovec, Z., Vreča, P., Samardžija, Z., VerbovÅ¡ek, T., Božič, D., Jamnikar, S., Solomon, D. K., Fernandez, D. P., Eastoe, C., McIntosh, J., Mori, N., & Grassa, F. (2019). The effect of geochemical processes on groundwater in the Velenje coal basin, Slovenia: insights from mineralogy, trace elements and isotopes signatures. SN Applied Sciences, 1(11), 1518.
• Markovich, K. H., Manning, A. H., Condon, L. E., & McIntosh, J. (2019). Mountain-Block Recharge: A Review of Current Understanding. Water Resources Research, 55(11), 8278-8304.
• McIntosh, J. C., & Ferguson, G. (2019). Conventional Oil—The Forgotten Part of the Water-Energy Nexus. Groundwater, 57(5), 669-677.
• Schweitzer, H., Ritter, D., Mcintosh, J. C., Barnhart, E., Cunningham, A., Vinson, D., Orem, W., & Fields, M. (2019). Changes in microbial communities and associated water and gas geochemistry across a sulfate gradient in coal beds: Powder River Basin, USA. Geochimica et Cosmochimica Acta, 245, 495-513.
• Vinson, D. S., Blair, N. E., Ritter, D. J., Martini, A. M., & McIntosh, J. C. (2019). Carbon mass balance, isotopic tracers of biogenic methane, and the role of acetate in coal beds: Powder River Basin (USA). Chemical Geology, 530, 119329.
• White, A., Moravec, B., McIntosh, J., Olshansky, Y., Paras, B., Sanchez, R. A., Ferré, T., Meixner, T., & Chorover, J. (2019). Distinct stores and the routing of water in the deep critical zone of a snow-dominated volcanic catchment. Hydrol. Earth Syst. Sci., 23(11), 4661-4683.
• Woroniuk, B., Tipton, K., Grasby, S. E., McIntosh, J. C., & Ferguson, G. (2019). Salt dissolution and permeability in the Western Canada Sedimentary Basin. Hydrogeology Journal, 27(1), 161-170.
• Zamora, H. A., Wilder, B. T., Eastoe, C. J., Mcintosh, J. C., Welker, J., & Flessa, K. W. (2019). Evaluation of groundwater sources, flow paths, and residence time of the Gran Desierto pozos, Sonora, Mexico. Geosciences, 9(378). doi:10.3390/geosciences9090378
• Ferguson, G., McIntosh, J. C., Grasby, S. E., Hendry, M. J., Jasechko, S., Lindsay, M., & Luijendijk, E. (2018). The Persistence of Brines in Sedimentary Basins. GEOPHYSICAL RESEARCH LETTERS, 45(10), 4851-4858.
• Ferguson, G., McIntosh, J. C., Perrone, D., & Jasechko, S. (2018). Competition for shrinking window of low salinity groundwater. ENVIRONMENTAL RESEARCH LETTERS, 13(11).
• Mcintosh, J. C., Hendry, M. J., Ballentine, C., Haszeldine, R. S., Mayer, B., Etiope, G., Elsner, M., Darrah, T. H., Prinzhofer, A., Osborn, S., Stalker, L., Kuloyo, O., Lu, Z., Martini, A., & Sherwood Lollar, B. (2018). A critical review of state-of-the-art and emerging approaches to identify fracking-derived gases and associated contaminants in aquifers. Environmental Science & Technology. doi:10.1021/acs.est.8b05807
• Olshansky, Y., White, A., Moravec, B., Mcintosh, J. C., & Chorover, J. D. (2018). Subsurface pore water contributions to stream concentration-discharge relations across a snowmelt hydrograph. Frontiers in Earth Science, 09 November 2018. doi:doi:org/10.3389/feart.2018.00181
• Shelton, J., Andrews, R. S., Akob, D. M., DeVera, C. A., Mumford, A., McCray, J. E., & McIntosh, J. C. (2018). Microbial community composition of a hydrocarbon reservoir 40 years after a CO2 enhanced oil recovery flood. FEMS MICROBIOLOGY ECOLOGY, 94(10).
• Woroniuk, B., Tipton, K., Ferguson, G., Grasby, S., & Mcintosh, J. C. (2018). Salt dissolution and permeability in the Western Canada Sedimentary basin. Hydrogeology Journal, 1-10.. doi:doi.org/10.1007/s10040-018-1871-6
• Zhang, Y., Person, M., Voller, V., Cohen, D., McIntosh, J., & Grapenthin, R. (2018). Hydromechanical Impacts of Pleistocene Glaciations on Pore Fluid Pressure Evolution, Rock Failure, and Brine Migration Within Sedimentary Basins and the Crystalline Basement. WATER RESOURCES RESEARCH, 54(10), 7577-7602.
• Li, L. i., Maher, K., Navarre-Sitchler, A., Druhan, J., Meile, C., Lawrence, C., Moore, J., Perdrial, J., Sullivan, P., Thompson, A., Jin, L., Bolton, E. W., Brantley, S. L., Dietrich, W. E., Mayer, K. U., Steefel, C. I., Valocchi, A., Zachara, J., Kocar, B., , Mcintosh, J., et al. (2017). Expanding the role of reactive transport models in critical zone processes. EARTH-SCIENCE REVIEWS, 165, 280-301.
• McIntosh, J. C., Schaumberg, C., Perdrial, J., Harpold, A., Vazquez-Ortega, A., Rasmussen, C., Vinson, D., Zapata-Rios, X., Brooks, P. D., Meixner, T., Pelletier, J., Derry, L., & Chorover, J. (2017). Geochemical evolution of the Critical Zone across variable time scales informs concentration-discharge relationships: Jemez River Basin Critical Zone Observatory. WATER RESOURCES RESEARCH, 53(5), 4169-4196.
• Morel, C., Tucci, R., & Mcintosh, J. (2017). Modeled impacts of sulfuric acid leaching solution on two groundwater types in the Upper Cienega Creek Watershed. ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY, 253.
• Vinson, D. S., Blair, N. E., Martini, A. M., Larter, S., Orem, W. H., & McIntosh, J. C. (2017). Microbial methane from in situ biodegradation of coal and shale: A review and reevaluation of hydrogen and carbon isotope signatures. CHEMICAL GEOLOGY, 453, 128-145.
• Barnhart, E. P., Weeks, E. P., Jones, E. J., Ritter, D. J., McIntosh, J. C., Clark, A. C., Ruppert, L. F., Cunningham, A. B., Vinson, D. S., Orem, W., & others, . (2016). Hydrogeochemistry and coal-associated bacterial populations from a methanogenic coal bed. International Journal of Coal Geology, 162, 14--26.
• Guido, Z., Mcintosh, J. C., Papuga, S. A., & Meixner, T. (2016). Seasonal glacial meltwater contributions to surface water in the Bolivian Andes: A case study using environmental tracers. Journal of Hydrology: Regional Studies, 8, 260-273.
• Huckle, D., Ma, L., Mcintosh, J. C., Vazquez-Ortega, A., Rasmussen, C., & Chorover, J. D. (2016). U-series isotopic signatures of soils and headwater streams in a semi-arid complex volcanic terrain. Chemical Geology, 445, 68-83.
• Shelton, J. L., Akob, D. M., McIntosh, J. C., Fierer, N., Spear, J. R., Warwick, P. D., & McCray, J. E. (2016). Environmental Drivers of Differences in Microbial Community Structure in Crude Oil Reservoirs across a Methanogenic Gradient. Frontiers in Microbiology, 7.
• Shelton, J. L., McIntosh, J. C., Hunt, A. G., Beebe, T. L., Parker, A. D., Warwick, P. D., Drake, R. M., & McCray, J. E. (2016). Determining CO2 storage potential during miscible CO2 enhanced oil recovery: Noble gas and stable isotope tracers. International Journal of Greenhouse Gas Control, 51, 239--253.
• Shelton, J. L., McIntosh, J. C., Warwick, P. D., & McCray, J. E. (2016). Impact of formation water geochemistry and crude oil biodegradation on microbial methanogenesis. Organic Geochemistry, 98, 105--117.
• Trostle, K. D., Runyon, J. R., Pohlmann, M., Redfield, S. E., Pelletier, J. D., Mcintosh, J. C., & Chorover, J. D. (2016). Colloids and organic matter complexation control trace metal concentration-dsicharge relationships in Marshall Gulch stream waters. Water Resources Research, 52, 7931-7944.
• Vazquez-Ortega, A., Huckle, D., Perdrial, J., Amistadi, M. K., Durcik, M., Rasmussen, C., Mcintosh, J. C., & Chorover, J. D. (2016). Solid-phase redistribution of rare earth elements in hillslope pedons subjected to different hydrologic fluxes. Chemical Geology, 426, 1-18.
• Zapata-Rios, X., Brooks, P. D., Troch, P. A., McIntosh, J., & Rasmussen, C. (2016). Influence of climate variability on water partitioning and effective energy and mass transfer (EEMT) in a semi-arid critical zone. Hydrol. Earth Syst. Sci. Discuss., 20, 1103-1115. doi:10.5194/hess-20-1103-2016
• Field, J. P., Breshears, D. D., Law, D. J., Villegas, J. C., Lopez-Hoffman, L., Brooks, P. D., Chorover, J., Barron-Gafford, G. A., Gallery, R. E., Litvak, M. E., Lybrand, R. A., McIntosh, J. C., Meixner, T., Niu, G., Papuga, S. A., Pelletier, J. D., Rasmussen, C. R., & Troch, P. A. (2015). Critical Zone Services: Expanding Context, Constraints, and Currency beyond Ecosystem Services. VADOSE ZONE JOURNAL, 14(1).
• Hamilton, S. M., Grasby, S. E., McIntosh, J. C., & Osborn, S. G. (2015). The effect of long-term regional pumping on hydrochemistry and dissolved gas content in an undeveloped shale-gas-bearing aquifer in southwestern Ontario, Canada. HYDROGEOLOGY JOURNAL, 23(4), 719-739.
• McIntosh, J. C., Hamilton, S. M., Grasby, S. E., & Osborn, S. G. (2015). Reply to Ryan et al. comment on "Origin, distribution and hydrogeochemical controls on methane occurrences in shallow aquifers, southwestern Ontario". APPLIED GEOCHEMISTRY.
• Ritter, D. J. (2015). Relationship Between Recharge, Redox Conditions, and Microbial Methane Generation in Coal Beds.
• Ritter, D., Vinson, D., Barnhart, E., Akob, D. M., Fields, M. W., Cunningham, A. B., Orem, W., & McIntosh, J. C. (2015). Enhanced microbial coalbed methane generation: A review of research, commercial activity, and remaining challenges. International Journal of Coal Geology, 28-41.
• Stielstra, C. M., Lohse, K. A., Chorover, J., McIntosh, J. C., Barron-Gafford, G. A., Perdrial, J. N., Litvak, M., Barnard, H. R., & Brooks, P. D. (2015). Climatic and landscape influences on soil moisture are primary determinants of soil carbon fluxes in seasonally snow-covered forest ecosystems. BIOGEOCHEMISTRY, 123(3), 447-465.
• Vazquez-Ortega, A., Perdrial, J., Harpold, A., Zapata-Rios, X., Rasmussen, C., McIntosh, J., Schaap, M., Pelletier, J. D., Brooks, P. D., Amistadi, M. K., & Chorover, J. (2015). Rare earth elements as reactive tracers of biogeochemical weathering in forested rhyolitic terrain. CHEMICAL GEOLOGY, 391, 19-32.
  More info

  Rare earth elements ( REEs) were evaluated as potential tracers of biogeochemical weathering at pedon, hillslope, and catchment scales in the Jemez River Basin Critical Zone Observatory (JRB-CZO), Valles Caldera National Preserve, NM, USA. We investigated time series of REE patterns in precipitation, soil pore water, groundwater, and stream water, and related these data to REE composition of soil, rock and atmospheric dust. REE signatures in stream waters are dynamic, reflecting processes that occur along hydrologic flowpaths during transport to the stream, including organic matter complexation, primary and secondary mineral weathering, water/soil/bedrock interaction, and atmospheric deposition. Strong compositional similarities for the REE between soil waters and stream waters during the initial snowmelt are consistent with shallow subsurface flows to streams. Most (bio) chemical denudation of REE occurred during the snowmelt-derived dissolved organic carbon (DOC) pulse, during which time apparent colloidal mobilization of REE occurred in association with Fe and Al (oxy) hydroxides. The REE and DOC concentrations in stream waters were positively correlated (R-2 = 0.80, p < 0.0001) during snowmelt, suggesting REE complexation and mobilization in association with organic ligands during the period of shallow subsurface flow. Positive Eu-anomalies occur in the soil matrix ([Eu / Eu*](RT) range from 1.79 to 2.52), soil solutions ([Eu / Eu*](RT) range from 1.89 to 5.98), and stream waters ([Eu / Eu*](RT) range from 1.01 to 2.27) with respect to the host lithologies-effects attributable to both eolian deposition and preferential feldspar dissolution. Cerium anomalies in soil solids and porewaters indicate seasonally dynamic translocation and oxidative accumulation in subsurface soil horizons (surface horizons: [Ce /Ce*] RT range from 0.70 to 1.1; subsurface horizons: [Ce / Ce*](RT) range from 0.95 to 1.29), consistent with prior research reporting Ce(IV) co-precipitation with Fe- and Mn-oxide minerals. (C) 2014 Elsevier B.V. All rights reserved.
• Wang, D. T., Gruen, D. S., Lollar, B. S., Hinrichs, K., Stewart, L. C., Holden, J. F., Hristov, A. N., Pohlman, J. W., Morrill, P. L., Koenneke, M., Delwiche, K. B., Reeves, E. P., Sutcliffe, C. N., Ritter, D. J., Seewald, J. S., McIntosh, J. C., Hemond, H. F., Kubo, M. D., Cardace, D., , Hoehler, T. M., et al. (2015). Nonequilibrium clumped isotope signals in microbial methane. SCIENCE, 348(6233), 428-431.
• Zapata-Rios, X. E., Brooks, P. D., Troch, P. A., & Mcintosh, J. C. (2015). Influence of terrain aspect on water partitioning, vegetation structure, and vegetation greening in high elevation catchments in northern New Mexico. Ecohydrology. doi:10.1002/eco.1674
• Zapata-Rios, X., McIntosh, J., Rademacher, L., Troch, P. A., Brooks, P. D., Rasmussen, C., & Chorover, J. (2015). Climatic and landscape controls on water transit times and silicate mineral weathering in the critical zone. WATER RESOURCES RESEARCH, 51(8), 6036-6051.
• Hopkins, C. B., McIntosh, J. C., Eastoe, C., Dickinson, J. E., & Meixner, T. (2014). Evaluation of the importance of clay confining units on groundwater flow in alluvial basins using solute and isotope tracers: the case of Middle San Pedro Basin in southeastern Arizona (USA). HYDROGEOLOGY JOURNAL, 22(4), 829-849.
  More info

  As groundwater becomes an increasingly important water resource worldwide, it is essential to understand how local geology affects groundwater quality, flowpaths and residence times. This study utilized multiple tracers to improve conceptual and numerical models of groundwater flow in the Middle San Pedro Basin in southeastern Arizona (USA) by determining recharge areas, compartmentalization of water sources, flowpaths and residence times. Ninety-five groundwater and surface-water samples were analyzed for major ion chemistry (water type and Ca/Sr ratios) and stable (O-18, H-2, C-13) and radiogenic (H-3, C-14) isotopes, and resulting data were used in conjunction with hydrogeologic information (e.g. hydraulic head and hydrostratigraphy). Results show that recent recharge (< 60 years) has occurred within mountain systems along the basin margins and in shallow floodplain aquifers adjacent to the San Pedro River. Groundwater in the lower basin fill aquifer (semi confined) was recharged at high elevation in the fractured bedrock and has been extensively modified by water-rock reactions (increasing F and Sr, decreasing C-14) over long timescales (up to 35,000 years BP). Distinct solute and isotope geochemistries between the lower and upper basin fill aquifers show the importance of a clay confining unit on groundwater flow in the basin, which minimizes vertical groundwater movement.
• Kanduc, T., Grassa, F., McIntosh, J., Stibilj, V., Ulrich-Supovec, M., Supovec, I., & Jamnikar, S. (2014). A geochemical and stable isotope investigation of groundwater/surface-water interactions in the Velenje Basin, Slovenia. HYDROGEOLOGY JOURNAL, 22(4), 971-984.
• McIntosh, J. C., Grasby, S. E., Hamilton, S. M., & Osborn, S. G. (2014). Origin, distribution and hydrogeochemical controls on methane occurrences in shallow aquifers, southwestern Ontario, Canada. APPLIED GEOCHEMISTRY, 50, 37-52.
  More info

  Natural gas reservoirs in organic-rich shales in the Appalachian and Michigan basins in the United States are currently being produced via hydraulic fracturing. Stratigraphically-equivalent shales occur in the Canadian portion of the basins in southwestern Ontario with anecdotal evidence of gas shows, yet there has been no commercial shale gas production to date. To provide baseline data in the case of future environmental issues related to hydraulic fracturing and shale gas production, such as leakage of natural gas, saline water, and/or hydraulic fracturing fluids, and to evaluate hydrogeochemical controls on natural gas accumulations in shallow groundwater in general, this study investigates the origin and distribution of natural gas and brine in shallow aquifers across southwestern Ontario. An extensive geochemical database of major ion and trace metal chemistry and methane concentrations of 1010 groundwater samples from shallow, domestic wells in bedrock and overburden aquifers throughout southwestern Ontario was utilized. In addition, select wells (n = 36) were resampled for detailed dissolved gas composition, delta C-13 of CH4, C-2, C-3, and CO2, and delta D of CH4. Dissolved gases in groundwater from bedrock and overburden wells were composed primarily of CH4 (29.7-98.6 mol% of total gas volume), N-2 (0.8-66.2 mol%), Ar + O-2 (0.2-3.4 mol%), and CO2 (0-1.2 mol%). Ethane was detected, but only in low concentrations ( 100 in situ % saturation) were found in bedrock wells completed in the Upper Devonian Kettle Point Formation, Middle Devonian Hamilton Group and Dundee Formation, and in surficial aquifers overlying these organic-rich shale-bearing formations, indicating that bedrock geology is the primary control on methane occurrences. A few (n = 40) samples showed Na-Cl-Br evidence of brine mixing with dilute groundwater, however only one of these samples contained high (>60 in situ % saturation) CH4. The relatively low delta C-13 values of CH4 (-89.9% to -57.3%), covariance of delta D values of CH4 and H2O, positive correlation between delta C-13 values of CH4 and CO2, and lack of higher chain hydrocarbons (C3+) in all but one dissolved gas sample indicates that the methane in groundwater throughout the study area is primarily microbial in origin. The presence or absence of alternative electron acceptors (e. g. dissolved oxygen, Fe, NO3, SO4), in addition to organic substrates, controls the occurrence of microbial CH4 in shallow aquifers. Microbial methane has likely been accumulating in the study area, since at least the Late Pleistocene to the present, as indicated by the co-variance and range of delta D values of CH4 (-314% to -263%) and associated groundwater (-19% to -6% delta D-H2O). (C) 2014 Elsevier Ltd. All rights reserved.
• Orem, W., Tatu, C., Varonka, M., Lerch, H., Bates, A., Engle, M., Crosby, L., & McIntosh, J. (2014). Organic substances in produced and formation water from unconventional natural gas extraction in coal and shale. INTERNATIONAL JOURNAL OF COAL GEOLOGY, 126, 20-31.
  More info

  Organic substances in produced and formation water from coalbed methane (CBM) and gas shale plays from across the USA were examined in this study. Disposal of produced waters from gas extraction in coal and shale is an important environmental issue because of the large volumes of water involved and the variable quality of this water. Organic substances in produced water may be environmentally relevant as pollutants, but have been little studied. Results from five CBM plays and two gas shale plays (including the Marcellus Shale) show a myriad of organic chemicals present in the produced and formation water. Organic compound classes present in produced and formation water in CBM plays include: polycyclic aromatic hydrocarbons (PAHs), heterocyclic compounds, alkyl phenols, aromatic amines, alkyl aromatics (alkyl benzenes, alkyl biphenyls), long-chain fatty acids, and aliphatic hydrocarbons. Concentrations of individual compounds range from
• Perdrial, J. N., McIntosh, J., Harpold, A., Brooks, P. D., Zapata-Rios, X., Ray, J., Meixner, T., Kanduc, T., Litvak, M., Troch, P. A., & Chorover, J. (2014). Stream water carbon controls in seasonally snow-covered mountain catchments: impact of inter-annual variability of water fluxes, catchment aspect and seasonal processes. BIOGEOCHEMISTRY, 118(1-3), 273-290.
  More info

  Stream water carbon (C) export is one important pathway for C loss from seasonally snow-covered mountain ecosystems and an assessment of overarching controls is necessary. However, such assessment is challenging because changes in water fluxes or flow paths, seasonal processes, as well as catchment specific characteristics play a role. For this study we elucidate the impact of: (i) changes in water flux (by comparing years of variable wetness), (ii) catchment aspect [north-facing (NF) vs. south-facing (SF)] and (iii) season (snowmelt vs. summer) on all forms of dissolved stream water C [dissolved organic C (DOC), chromophoric dissolved organic matter (CDOM) and dissolved inorganic C (DIC)] in forested catchments within the Valles Caldera National Preserve, New Mexico. The significant correlation between annual water and C fluxes (e.g. DOC r(2) = 0.83, p < 0.02) confirms annual stream water discharge as the overarching control on C efflux, likely from a well-mixed ground water reservoir as indicated by previous research. However, CDOM exhibited a dominantly terrestrial fluorescence signature (59-71 %) year round, signaling a strong riparian and near stream soil control on CDOM composition. During snowmelt, the role of water as C transporter was superimposed on its control as C reservoir, when the NF stream transported significantly more soil C (40 % DOC, 56 % DIC) than the SF stream as a result of hillslope flushing. Inter-annual variations in winter precipitation were paramount in regulating annual stream C effluxes, e.g., reducing C effluxes three-fold after a dry (relative to wet) winter season. During the warmer summer months % dissolved oxygen saturation decreased, delta C-13(DIC) increased and CDOM assumed a more microbial signature, consistent with heterotrophic respiration in the stream and riparian soils. As a result of stream C incubation and soil respiration, increased up to 12 times atmospheric values leading to substantial degassing.
• Shelton, J. L., McIntosh, J. C., Warwick, P. D., & Yi, A. L. (2014). Fate of injected CO2 in the Wilcox Group, Louisiana, Gulf Coast Basin: Chemical and isotopic tracers of microbial-brine-rock-CO2 interactions. APPLIED GEOCHEMISTRY, 51, 155-169.
  More info

  The "2800' sandstone'' of the Olla oil field is an oil and gas-producing reservoir in a coal-bearing interval of the Paleocene-Eocene Wilcox Group in north-central Louisiana, USA. In the 1980s, this producing unit was flooded with CO2 in an enhanced oil recovery (EOR) project, leaving similar to 30% of the injected CO2 in the 2800' sandstone post-injection. This study utilizes isotopic and geochemical tracers from co-produced natural gas, oil and brine to determine the fate of the injected CO2, including the possibility of enhanced microbial conversion of CO2 to CH4 via methanogenesis. Stable carbon isotopes of CO2, CH4 and DIC, together with mol% CO2 show that 4 out of 17 wells sampled in the 2800' sandstone are still producing injected CO2. The dominant fate of the injected CO2 appears to be dissolution in formation fluids and gas-phase trapping. There is some isotopic and geochemical evidence for enhanced microbial methanogenesis in 2 samples; however, the CO2 spread unevenly throughout the reservoir, and thus cannot explain the elevated indicators for methanogenesis observed across the entire field. Vertical migration out of the target 2800' sandstone reservoir is also apparent in 3 samples located stratigraphically above the target sand. Reservoirs comparable to the 2800' sandstone, located along a 90-km transect, were also sampled to investigate regional trends in gas composition, brine chemistry and microbial activity. Microbial methane, likely sourced from biodegradation of organic substrates within the formation, was found in all oil fields sampled, while indicators of methanogenesis (e.g. high alkalinity, delta C-13-CO2 and delta C-13-DIC values) and oxidation of propane were greatest in the Olla Field, likely due to its more ideal environmental conditions (i.e. suitable range of pH, temperature, salinity, sulfate and iron concentrations). Published by Elsevier Ltd.
• Kanduc, T., Sturm, M. B., & McIntosh, J. (2013). Chemical Dynamics and Evaluation of Biogeochemical Processes in Alpine River Kamnika Bistrica, North Slovenia. AQUATIC GEOCHEMISTRY, 19(4), 323-346.
• Pelletier, J. D., Barron-Gafford, G. A., Breshears, D. D., Brooks, P. D., Chorover, J., Durcik, M., Harman, C. J., Huxman, T. E., Lohse, K. A., Lybrand, R., Meixner, T., McIntosh, J. C., Papuga, S. A., Rasmussen, C., Schaap, M., Swetnam, T. L., & Troch, P. A. (2013). Coevolution of nonlinear trends in vegetation, soils, and topography with elevation and slope aspect: A case study in the sky islands of southern Arizona. JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE, 118(2), 741-758.
  More info

  Feedbacks among vegetation dynamics, pedogenesis, and topographic development affect the critical zonethe living filter for Earth's hydrologic, biogeochemical, and rock/sediment cycles. Assessing the importance of such feedbacks, which may be particularly pronounced in water-limited systems, remains a fundamental interdisciplinary challenge. The sky islands of southern Arizona offer an unusually well-defined natural experiment involving such feedbacks because mean annual precipitation varies by a factor of five over distances of approximately 10 km in areas of similar rock type (granite) and tectonic history. Here we compile high-resolution, spatially distributed data for Effective Energy and Mass Transfer (EEMT: the energy available to drive bedrock weathering), above-ground biomass, soil thickness, hillslope-scale topographic relief, and drainage density in two such mountain ranges (Santa Catalina: SCM; Pinaleno: PM). Strong correlations exist among vegetation-soil-topography variables, which vary nonlinearly with elevation, such that warm, dry, low-elevation portions of these ranges are characterized by relatively low above-ground biomass, thin soils, minimal soil organic matter, steep slopes, and high drainage densities; conversely, cooler, wetter, higher elevations have systematically higher biomass, thicker organic-rich soils, gentler slopes, and lower drainage densities. To test if eco-pedo-geomorphic feedbacks drive this pattern, we developed a landscape evolution model that couples pedogenesis and topographic development over geologic time scales, with rates explicitly dependent on vegetation density. The model self-organizes into states similar to those observed in SCM and PM. Our results highlight the potential importance of eco-pedo-geomorphic feedbacks, mediated by soil thickness, in water-limited systems.
• Schlegel, M. E., McIntosh, J. C., Petsch, S. T., Orem, W. H., Jones, E. J., & Martini, A. M. (2013). Extent and limits of biodegradation by in situ methanogenic consortia in shale and formation fluids. APPLIED GEOCHEMISTRY, 28, 172-184.
• Zavadlav, S., Kanduc, T., McIntosh, J., & Lojen, S. (2013). Isotopic and Chemical Constraints on the Biogeochemistry of Dissolved Inorganic Carbon and Chemical Weathering in the Karst Watershed of Krka River (Slovenia). AQUATIC GEOCHEMISTRY, 19(3), 209-230.
• Dejwakh, N. R., Meixner, T., Michalski, G., & McIntosh, J. (2012). Using O-17 to Investigate Nitrate Sources and Sinks in a Semi-Arid Groundwater System. ENVIRONMENTAL SCIENCE & TECHNOLOGY, 46(2), 745-751.
• Gallo, E. L., Lohse, K. A., Brooks, P. D., McIntosh, J. C., Meixner, T., & McLain, J. E. (2012). Quantifying the effects of stream channels on storm water quality in a semi-arid urban environment. JOURNAL OF HYDROLOGY, 470, 98-110.
  More info

  Stormwater drainage systems can have a large effect on urban runoff quality, but it is unclear how ephemeral urban streams alter runoff hydrochemistry. This problem is particularly relevant in semi-arid regions, where urban storm runoff is considered a renewable water resource. Here we address the question: how do stream channels alter urban runoff hydrochemistry? We collected synoptic stormwater samples during three rainfall-runoff events from nine ephemeral streams reaches (three concrete or metal, three grass, three gravel) in Tucson, Arizona. We identified patterns of temporal and spatial (longitudinal) variability in concentrations of conservative (chloride and isotopes of water) and reactive solutes (inorganic-N, soluble reactive phosphorous, sulfate-S, dissolved organic carbon (DOC) and nitrogen, and fecal indicator bacteria). Water isotopes and chloride (Cl) concentrations indicate that solute flushing and evapoconcentration alter temporal patterns in runoff hydrochemistry, but not spatial hydrochemical responses. Solute concentrations and stream channel solute sourcing and retention during runoff were significantly more variable at the grass reaches (CV = 2.3 - 144%) than at the concrete or metal (CV = 1.6 - 107%) or gravel reaches (CV = 1.9 - 60%), which functioned like flow-through systems. Stream channel soil Cl and DOC decreased following a runoff event (Cl: 12.1-7.3 mu g g(-1) soil; DOC: 87.7-30.1 mu g g(-1) soil), while soil fecal indicator bacteria counts increased (55-215 CFU g(-1) soil). Finding from this study suggest that the characteristics of the ephemeral stream channel substrate control biogeochemical reactions between runoff events, which alter stream channel soil solute stores and the hydrochemistry of subsequent runoff events. (C) 2012 Elsevier B.V. All rights reserved.
• Kanduc, T., Markic, M., Zavsek, S., & McIntosh, J. (2012). Carbon cycling in the Pliocene Velenje Coal Basin, Slovenia, inferred from stable carbon isotopes. INTERNATIONAL JOURNAL OF COAL GEOLOGY, 89(1), 70-83.
• Kandu{\v{c}}, T., {\v{S}}turm, M., {\v{Z}}igon, S., & McIntosh, J. (2012). Tracing biogeochemical processes and pollution sources with stable isotopes in river systems: Kamni{\v{s}}ka Bistrica, North Slovenia. Biogeosciences Discussions, 9(7), 9711--9757.
• Mcintosh, J. C., Schlegel, M. E., & Person, M. (2012). Glacial impacts on hydrologic processes in sedimentary basins: Evidence from natural tracer studies. Geofluids, 12(1), 7-21.
  More info

  Abstract: This study reviews and synthesizes the results from geochemical and isotopic case studies across Europe, North America, Antarctica, and Greenland to evaluate the effects of Pleistocene glaciation on continental-scale groundwater circulation in sedimentary basins. The most effective studies, in terms of delineating high-resolution records of paleorecharge to aquifers, combine solute chemistry, stable isotopes of water, age tracers, and dissolved noble gases. Some of the lowest δ 18O values (-22‰), and noble gas temperatures (0°C), and high excess air concentrations were found in confined groundwaters in northern Estonia, likely derived from Scandinavian Ice Sheet subglacial recharge. These results are consistent with groundwater systems in North America that were recharged beneath the Laurentide Ice Sheet. Late Pleistocene precipitation may have also been an important source of recharge, as indicated by low-temperature, isotopically enriched groundwaters in several basins. Detectable age gaps have been observed in several aquifer systems in North America and Europe, likely caused by a hiatus of groundwater recharge in areas covered by permafrost during the Last Glacial Maximum (10-21ka). Aquifers that were not covered by ice sheets or permafrost contain continuous records of Pleistocene to Holocene recharge with variable δ 18O values and low paleotemperatures (4-9°C lower than today). The maximum depth of glacial meltwater penetration into sedimentary basins is approximately 50-1000m. Infiltration of dilute meltwaters dissolved large quantities of halite in evaporite-bearing basins. The presence of clay-rich glacial deposits and bedrock confining units enhanced the storage of meltwaters within low-permeability sediments and limited flushing of paleowaters in underlying aquifers. These results demonstrate the importance of continental glaciation as a driver for basinal-scale fluid and solute transport and have implications for long-term storage of radioactive waste and carbon dioxide at depth in high-latitude sedimentary basins. © 2011 Blackwell Publishing Ltd.
• Osborn, S. G., McIntosh, J. C., Hanor, J. S., & Biddulph, D. (2012). Iodine-129, 87Sr/86Sr, and trace elemental geochemistry of northern Appalachian Basin brines: Evidence for basinal-scale fluid migration and clay mineral diagenesis. American Journal of Science, 312(3), 263--287.
• Person, M., Mcintosh, J. C., Iverson, N., Neuzil, C. E., & Bense, V. (2012). Editorial: Geologic isolation of nuclear waste at high latitudes: the role of ice sheets. Geofluids.
• Bates, B. L., McIntosh, J. C., Lohse, K. A., & Brooks, P. D. (2011). Influence of groundwater flowpaths, residence times and nutrients on the extent of microbial methanogenesis in coal beds: Powder River Basin, USA. CHEMICAL GEOLOGY, 284(1-2), 45-61.
  More info

  Water and natural gas samples were collected from coalbed methane wells and a surface coal mine in the Powder River Basin (PRB) and analyzed for solute chemistry, isotopes, and gas composition to test hypotheses about the timing and source of recharge, importance of nutrient influx, and extent of microbial methanogenesis in coalbeds. Recharge to the Wyodak-Anderson coal zone in the central portions of the PRB appears to be from the southern basin Margin based on delta(18)O-H(2)O values and hydraulic gradients. Coal zones along the eastern margin, near the coal outcrop, represent mixing between surface water and deeper circulating groundwater. Coalbeds along the northwestern basin margin may contain high elevation recharge from the Bighorn Mountains, with flow patterns likely affected by local faults. Detectable (14)C (0.39 to 4.13 pmC) in coal waters throughout the PRB indicates they were recharged
• Brown, K. B., McIntosh, J. C., Rademacher, L. K., & Lohse, K. A. (2011). Impacts of agricultural irrigation recharge on groundwater quality in a basalt aquifer system (Washington, USA): a multi-tracer approach. HYDROGEOLOGY JOURNAL, 19(5), 1039-1051.
• Carlson, M. A., Lohse, K. A., McIntosh, J. C., & McLain, J. E. (2011). Impacts of urbanization on groundwater quality and recharge in a semi-arid alluvial basin. JOURNAL OF HYDROLOGY, 409(1-2), 196-211.
• Chorover, J., Troch, P. A., Rasmussen, C., Brooks, P. D., Pelletier, J. D., Breshears, D. D., Huxman, T. E., Kurc, S. A., Lohse, K. A., McIntosh, J. C., Meixner, T., Schaap, M. G., Litvak, M. E., Perdrial, J., Harpold, A., & Durcik, M. (2011). How Water, Carbon, and Energy Drive Critical Zone Evolution: The Jemez-Santa Catalina Critical Zone Observatory. VADOSE ZONE JOURNAL, 10(3), 884-899.
• McIntosh, J. C., Garven, G., & Hanor, J. S. (2011). Impacts of Pleistocene glaciation on large-scale groundwater flow and salinity in the Michigan Basin. Geofluids, 11(1), 18-33.
  More info

  Abstract: Pleistocene melting of kilometer-thick continental ice sheets significantly impacted regional-scale groundwater flow in the low-lying stable interiors of the North American and Eurasian cratons. Glacial meltwaters penetrated hundreds of meters into the underlying sedimentary basins and fractured crystalline bedrock, disrupting relatively stagnant saline fluids and creating a strong disequilibrium pattern in fluid salinity. To constrain the impact of continental glaciation on variable density fluid flow, heat and solute transport in the Michigan Basin, we constructed a transient two-dimensional finite-element model of the northern half of the basin and imposed modern versus Pleistocene recharge conditions. The sag-type basin contains up to approximately 5km of Paleozoic strata (carbonates, siliciclastics, and bedded evaporites) overlain by a thick veneer (up to 300m) of glacial deposits. Formation water salinity increases exponentially from 350gl-1 TDS at over 800m depth. Model simulations show that modern groundwater flow is primarily restricted to shallow glacial drift aquifers with discharge to the Great Lakes. During the Pleistocene, however, high hydraulic heads from melting of the Laurentide Ice Sheet reversed regional flow patterns and focused recharge into Paleozoic carbonate and siliciclastic aquifers. Dilute waters (
• Schlegel, M. E., McIntosh, J. C., Bates, B. L., Kirk, M. F., & Martini, A. M. (2011). Comparison of fluid geochemistry and microbiology of multiple organic-rich reservoirs in the Illinois Basin, USA: Evidence for controls on methanogenesis and microbial transport. GEOCHIMICA ET COSMOCHIMICA ACTA, 75(7), 1903-1919.
  More info

  Microbial methane in sedimentary basins comprises approximately 20% of global natural gas resources, yet little is known about the environmental requirements and metabolic rates of these subsurface microbial communities. The Illinois Basin, located in the midcontinent of the United States, is an ideal location to investigate hydrogeochemical factors controlling methanogenesis as microbial methane accumulations occur: (1) in three organic-rich reservoirs of different geologic ages and organic matter types - Upper Devonian New Albany Shale (up to 900 m depth), Pennsylvanian coals (up to 600 m depth), and Quaternary glacial sediments (shallow aquifers); (2) across steep salinity gradients; and (3) with variable concentrations of SO(4)(2-). For all three organic-rich reservoirs aqueous geochemical conditions are favorable for microbial methanogenesis, with near neutral pH, SO(4)(2-) concentrations < 2 mM, and Cl(-) concentrations < 3 M. Also, carbon isotopic fractionation of CH(4), CO(2), and DIC is consistent with microbial methanogenesis, and increased carbon isotopic fractionation with average reservoir depth corresponds to a decrease of groundwater flushing rates with average depth of reservoir. Plots of stable isotopes of water and Cl(-) show mixing between a brine endmember and freshwater, suggesting that meteoric groundwater recharge has affected all microbial methanogenic systems. Additionally, similar methanogenic communities are present in all three reservoirs with comparable cell counts (8.69E3-2.58E6 cells/mL). TRFLP results show low numbers of archaea species with only two dominant groups of base pairs in coals, shale, and limestone aquifers. These results compare favorably with other methanogen-containing deep subsurface environments. Individual hydrogeochemical parameters that have a Spearman correlation coefficient greater than 0.3 to variations in methanogenic species include stable isotopes of water (delta(18)O and delta D), type of substrate (i.e. coals versus shale), pH, and Cl(-) concentration. The matching of variations between methanogenic TRFLP data and conservative tracers suggests that deep circulation of meteoric waters influenced archaeal communities in the Illinois Basin. In addition, coalification and burial estimates suggest that in the study area, coals and shale reservoirs were previously sterilized (> 80 degrees C in nutrient poor environments), necessitating the re-introduction of microbes into the subsurface via groundwater transport. (C) 2011 Elsevier Ltd. All rights reserved.
• Schlegel, M. E., Zhou, Z., McIntosh, J. C., Ballentine, C. J., & Person, M. A. (2011). Constraining the timing of microbial methane generation in an organic-rich shale using noble gases, Illinois Basin, USA. CHEMICAL GEOLOGY, 287(1-2), 27-40.
• Vinson, D. S., McIntosh, J. C., Dwyer, G. S., & Vengosh, A. (2011). Arsenic and other oxyanion-forming trace elements in an alluvial basin aquifer: Evaluating sources and mobilization by isotopic tracers (Sr, B, S, O, H, Ra). APPLIED GEOCHEMISTRY, 26(8), 1364-1376.
• Brown, K., Mcintosh, J. C., Baker, V. R., & Gosch, D. (2010). Isotopically-depleted Late Pleistocene groundwater in Columbia River Basalts: evidence for recharge of Glacial Lake Missoula floodwaters?. Geophysical Research Letters, 37(L21402), doi:10.1029/2010GL044992.
• Kanduc, T., Mcintosh, J. C., & Jamnikar, . (2010). Geochemical characteristics of surface waters and groundwaters in the Velenje Basin, Slovenia. Geologija, 53/1, 37-46.
• McIntosh, J. C., Warwick, P. D., Martini, A. M., & Osborn, S. G. (2010). Coupled hydrology and biogeochemistry of Paleocene--Eocene coal beds, northern Gulf of Mexico. Geological Society of America Bulletin, 122(7-8), 1248--1264.
• Osborn, S. G., & McIntosh, J. C. (2010). Chemical and isotopic tracers of the contribution of microbial gas in Devonian organic-rich shales and reservoir sandstones, northern Appalachian Basin. Applied Geochemistry, 25(3), 456-471.
  More info

  Abstract: In this study, the geochemistry and origin of natural gas and formation waters in Devonian age organic-rich shales and reservoir sandstones across the northern Appalachian Basin margin (western New York, eastern Ohio, northwestern Pennsylvania, and eastern Kentucky) were investigated. Additional samples were collected from Mississippian Berea Sandstone, Silurian Medina Sandstone and Ordovician Trenton/Black River Group oil and gas wells for comparison. Dissolved gases in shallow groundwaters in Devonian organic-rich shales along Lake Erie contain detectable CH4 (0.01-50.55 mol%) with low δ13C-CH4 values (-74.68 to -57.86‰) and no higher chain hydrocarbons, characteristics typical of microbial gas. Nevertheless, these groundwaters have only moderate alkalinity (1.14-8.72 meq/kg) and relatively low δ13C values of dissolved inorganic C (DIC) (-24.8 to -0.6‰), suggesting that microbial methanogenesis is limited. The majority of natural gases in Devonian organic-rich shales and sandstones at depth (>168 m) in the northern Appalachian Basin have a low CH4 to ethane and propane ratios (3-35 mol%; C1/C2 + C3) and high δ13C and δD values of CH4 (-53.35 to -40.24‰, and -315.0 to -174.6‰, respectively), which increase in depth, reservoir age and thermal maturity; the molecular and isotopic signature of these gases show that CH4 was generated via thermogenic processes. Despite this, the geochemistry of co-produced brines shows evidence for microbial activity. High δ13C values of DIC (>+10‰), slightly elevated alkalinity (up to 12.01 meq/kg) and low SO4 values (
• Person, M., Banerjee, A., Rupp, J., Medina, C., Lichtner, P., Gable, C., Pawar, R., Celia, M., McIntosh, J., & Bense, V. (2010). Assessment of basin-scale hydrologic impacts of CO₂ sequestration, Illinois basin. International Journal of Greenhouse Gas Control, 4(5), 840-854.
  More info

  Abstract: Idealized, basin-scale sharp-interface models of CO2 injection were constructed for the Illinois basin. Porosity and permeability were decreased with depth within the Mount Simon Formation. Eau Claire confining unit porosity and permeability were kept fixed. We used 726 injection wells located near 42 power plants to deliver 80 million metric tons of CO2/year. After 100 years of continuous injection, deviatoric fluid pressures varied between 5.6 and 18 MPa across central and southern part of the Illinois basin. Maximum deviatoric pressure reached about 50% of lithostatic levels to the south. The pressure disturbance (>0.03 MPa) propagated 10-25 km away from the injection wells resulting in significant well-well pressure interference. These findings are consistent with single-phase analytical solutions of injection. The radial footprint of the CO2 plume at each well was only 0.5-2 km after 100 years of injection. Net lateral brine displacement was insignificant due to increasing radial distance from injection well and leakage across the Eau Claire confining unit. On geologic time scales CO2 would migrate northward at a rate of about 6 m/1000 years. Because of paleo-seismic events in this region (M5.5-M7.5), care should be taken to avoid high pore pressures in the southern Illinois basin. © 2010 Elsevier Ltd.
• Kirk, M. F., Martini, A. M., McIntosh, J. C., Petsch, S. T., & Takacs-Vesbach, C. (2009). Effect of natural gas production on geochemistry and microbiology in a fractured organic-rich shale. Geochimica et Cosmochimica Acta Supplement, 73, 661.
• Osborn, S. G., & McIntosh, J. C. (2009). 129I and Sr isotopes as tracers of large-scale fluid migration in the northern Appalachian Basin (USA). Geochimica et Cosmochimica Acta Supplement, 73, 976.
• Martini, A. M., Walter, L. M., & McIntosh, J. C. (2008). Identification of microbial and thermogenic gas components from Upper Devonian black shale cores, Illinois and Michigan basins. AAPG Bulletin, 92(3), 327-339.
  More info

  Abstract: Differentiation of microbial versus thermogenic methane in coalbed and black shale accumulations can affect strategies for exploration and may influence the total gas content in a given area. Early identification of these processes from crushed core materials, even before formation fluids and produced gas samples are available, could permit a more efficient and cost-effective exploration. Total gas contents and compositional and isotopic data from New Albany Shale core materials are presented, which delineate regional occurrence of microbial, thermogenic, and mixed gas generation in the Illinois Basin. These trends are consistent with those identified from detailed prior studies of produced gas and water chemistry from the same locations. The most useful markers for microbial gas in crushed core gases are elevated CO2 contents characterized by high δ13 CCO2 values (> 5‰). Core gas analyses from wells in which microbial gas is identified commonly have significantly more total gas absorbed than do core samples from wells producing gases solely of thermogenic origin. These observations are independent of variations in sample depth and organic carbon content in a given core. Thus, this integrated case study of core and produced gases in the Illinois Basin illustrates that the areas containing microbial gas, in addition to early thermogenic gas, may be more productive than pure thermogenic zones for these early to immature unconventional gas deposits. Copyright © 2008. The American Association of Petroleum Geologists. All rights reserved.
• McIntosh, J. C., & Martini, A. M. (2008). Chapter Five: Hydrogeochemical Indicators for Microbial Methane in Fractured Organic-Rich Shales: Case Studies of the Antrim, New Albany, and Ohio Shales.
• McIntosh, J., & Martini, A. (2008). Hydrogeochemical indicators for microbial methane in fractured black shales: case studies of the Antrim, New Albany, and Ohio shales. Gas Shale in the Rocky Mountains and Beyond, Rocky Mountain Association of Geologists, 162--174.
• McIntosh, J., Martini, A., Petsch, S., Huang, R., & Nüsslein, K. (2008). Biogeochemistry of the Forest City Basin coalbed methane play. International Journal of Coal Geology, 76(1-2), 111-118.
  More info

  Abstract: Hydrogeochemical and microbial analyses of co-produced formation waters and gas in the Forest City Basin were coupled to determine the origin of methane in shallow coal seams and make comparisons to commercial shale and coal gas plays in the adjacent Illinois, Michigan and Cherokee basins. Forest City Basin coals contain dilute meteoric waters (Cl- < 411 mM; average δ18O and δD values = - 6.9‰ and - 45.6‰ VSMOW, respectively), no detectable SO42-, and high alkalinity concentrations (~ 10 meq/L) with elevated δ13C values (up to 13.1‰ VPDB). The δ13C values of coalbed methane (average = - 64.7‰ VPDB) are approximately 72‰ depleted relative to the potential dissolved inorganic carbon source, and the δD values of CH4 (average = - 221‰ VSMOW) are approximately - 175‰ depleted compared with ambient formation waters. Together, these molecular and isotopic signatures of Forest City Basin waters and gas point to a microbial origin for methane. Enrichment cultures of microbial cells inoculated from Forest City Basin coal waters confirm the presence of a microbial community of fermentative bacteria, and both CO2-reducing and acetate-utilizing forms of methanogenic Archaea, similar to what has been observed in the Antrim Shale in the Michigan Basin. © 2008 Elsevier B.V. All rights reserved.
• Schlegel, M., McIntosh, J., Person, M., Ballentine, C., & Zheng, Z. (2008). Investigating the source and timing of freshwater recharge into saline aquifers in the glaciated Illinois Basin. Geochimica et Cosmochimica Acta Supplement, 72, A832.
• Hanor, J. S., & Mcintosh, J. C. (2007). Diverse origins and timing of formation of basinal brines in the Gulf of Mexico sedimentary basin. Geofluids, 7(2), 227-237.
  More info

  Abstract: A review of five different field areas in the Gulf of Mexico sedimentary basin (GOM) illustrates some of the potentially diverse chemical and physical processes which have produced basinal brines. The elevated salinities of most of the formation waters in the GOM are ultimately related to the presence of the Middle Jurassic Louann Salt. Some of these brines likely inherited their salinity from evaporated Mesozoic seawater, while other saline fluids have been produced by subsequent dissolution of salt, some of which is occurring today. The timing of the generation of brines has thus not been restricted to the Middle Jurassic. The mechanisms of solute transport that have introduced brines throughout much of the sedimentary section of the GOM are not entirely understood. Free convection driven by spatial variations in formation water temperature and salinity is undoubtedly occurring around some salt structures. However, the driving mechanisms for the broad, diffusive upward solute transport in the northern Gulf rim of Arkansas and northern Louisiana are not known. In the Lower Cretaceous of Texas, fluid flow was much more highly focused, and perhaps episodic. It is clear that many areas of the Gulf basin are hydrologically connected and that large-scale fluid flow, solute transport, and dispersion have occurred. The Na-Mg-Ca-Cl compositions of brines in the areas of the Gulf Coast sedimentary basin reviewed in this article are products of diagenesis and do not reflect the composition of the evaporated marine waters present at the time of sediment deposition. Large differences in Na, Ca, and Mg trends for waters hosted by Mesozoic versus Cenozoic sediments may reflect differences in: (i) the sources of salinity (evaporated seawater for some of the Mesozoic sediments, dissolution of salt for some of the Cenozoic sediments); (ii) sediment lithology (dominantly carbonates for much of the Mesozoic sediments, and dominantly siliciclastics for the Cenozoic sediments); or (iii) residence times of brines associated with these sediments (tens of millions of years versus perhaps days). © 2007 The Author Journal compilation © 2007 Blackwell Publishing Ltd.
• McIntosh, J., Warwick, P., Martini, A., & Osborn, S. (2007). Geochemical linkages between groundwater flow and microbial methane generation in shallow coal beds and fractured black shales—northern Gulf of Mexico and midcontinent US basins. American Association of Petroleum Geologists, 92.
• Person, M., McIntosh, J., Bense, V., & Remenda, V. H. (2007). Pleistocene hydrology of North America: The role of ice sheets in reorganizing groundwater flow systems. Reviews of Geophysics, 45(3).
  More info

  Abstract: While the geomorphic consequences of Pleistocene megafloods have been known for some time, it has been only in the past 2 decades that hydrogeologists and glaciologists alike have begun to appreciate the important impact at ice sheet-aquifer interactions have had in controlling subsurface flow patterns, recharge rates, and the distribution of fresh water in confined aquifer systems across North America. In this paper, we document the numerous lines of geochemical, isotopic, and geomechanical evidence of ice sheet hydrogeology across North America. We also review the mechanical, thermal, and hydrologic processes that control subsurface fluid migration beneath ice sheets. Finite element models of subsurface fluid flow, permafrost formation, and ice sheet loading are presented to investigate the coupled nature of transport processes during glaciation/deglaciation. These indicate that recharge rates as high as 10 times modern values occurred as the Laurentide Ice Sheet overran the margins of sedimentary basins. The effects cf ice sheet loading and permafrost formation result in complex transient flow patterns within aquifers and confining units alike. Using geochemical and environmental isotopic data, we estimate that the volume of glacial meltwater emplaced at the margins of sedimentary basins overrun by the Laurentide Ice Sheet totals about 3.7 × 104 km3, which is about 0.2% of the volume of the Laurentide Ice Sheet. Subglacial infiltration estimates based on continental-scale hydrologic models are even higher (5-10% of meltwater generated). These studies in sum call into question the widely held notion that groundwater flow patterns within confined aquifer systems are controlled primarily by the water table configuration during the Pleistocene. Rather, groundwater flow patterns were likely much more complex and transient in nature than has previously been thought. Because Pleistocene recharge rates are believed to be highly variable, these studies have profound implications for water resource managers charged with determining sustainable pumping rates from confined aquifers that host ice sheet meltwater. Copyright 2007 by the American Geophysical Union.
• Szramek, K., McIntosh, J. C., Williams, E. L., Kanduc, T., Ogrinc, N., & Walter, L. M. (2007). Relative weathering intensity of calcite versus dolomite in carbonate-bearing temperate zone watersheds: Carbonate geochemistry and fluxes from catchments within the St. Lawrence and Danube river basins. Geochemistry, Geophysics, Geosystems, 8(4).
  More info

  Abstract: Calcite and dolomite solubilities in open weathering environments are proportional to pCO2 and inversely proportional to temperature, and dolomite solubility is progressively greater than calcite below 25°C. The continent-scale weathering budget reveals the significance of the Northern Hemisphere (NH) to globally integrated riverine fluxes of Ca2+, Mg2+, and HCO3-. The NH contributes 70% of the global HCO3- flux while only 54% of the riverine discharge. We present results of a comparative hydrogeochemical study of carbonate mineral equilibria and weathering fluxes in two NH carbonaterich river basins. Surface water geochemistry and discharge were determined for head water streams in Michigan and Slovenia within the St. Lawrence and Danube river basins. Michigan watersheds are established atop carbonate-bearing glacial drift deposits derived from erosion of Paleozoic strata with thick soil horizons (100-300 cm). Slovenia watersheds drain Mesozoic bedrock carbonates in alpine and dinaric karst environments with thin soil horizons (0-70 cm). Carbonate weathering intensity is a parameter that normalizes river runoff and HCO 3- concentration to catchment area (meq HCO 3- km-2 s-1), summing calcite and dolomite contributions, and is used to gauge the effects of climate, land use, and soil thickness on organic-inorganic carbon processing rates. Importantly, Michigan riverine discharge is one-tenth of Slovenian rivers, providing the opportunity to evaluate the kinetics of carbonate mineral equilibration. The study rivers are HCO3- - Ca2+ - Mg2+ waters, supersaturated for calcite at pCO2 values in excess of theatmosphere. As discharge varies, HCO3- concentrations differ by less than 20% for any location, and Mg2+/ Ca2+ remains relatively fixed for Michigan (0.5) and Slovenia streams (0.4), requiring that dolomite dissolution exceed calcite on a mole basis. The ability of calcite and dolomite dissolution to keep pace with increased discharge indicates carbonate weathering is limited only by water flux and temperaturedependent solubility in these watersheds. Carbonate weathering intensity in Michigan and Slovenia exceeds the world average by factors between 2 and 20, and dolomite weathering intensity, estimated from riverine Mg 2+ fluxes, exceeds the world average by factors between 2 and 15. Thus global fluxes of carbonate-related weathering products appear heavily skewed toward carbonate-bearing environments at higher latitudes with relatively low mean annual temperatures and high discharge. Copyright 2007 by the American Geophysical Union.
• Cheng, J., McIntosh, J. C., Xie, X., & Jiao, J. J. (2006). Hydrochemistry of formation water with implication to diagenetic reactions in Sanzhao depression and Qijia-gulong depression of Songliao Basin, China. Journal of Geochemical Exploration, 88(1-3 SPEC. ISS.), 86-90.
  More info

  Abstract: The Sanzhao depression and Qijia-gulong depression are two of the most important hydrocarbon-bearing sub-depressions in the Songliao basin, dominated by Cretaceous fluvial and lacustrine strata with volcanic and volcaniclastic rocks. In this paper, the pressure distributions and hydrochemistry variations in those two depressions are investigated. It is found that the Qijia-gulong depression is dominated by overpressure, but the Sanzhao depression is dominated by underpressure, especially in the Quantou formation. The salinity of formation water ranges from 1.0 g/ L to 20 g/L, with a mean of 4 g/L in most formations. Water composition is dominated by NaHCO3 water type but varies greatly in salinity and ionic ratios in the different depressions. The results of mass balance calculation reveal that, fluid chemistry in the Qijia-gulong depression is dominated by dissolution of silicate minerals and halite, whereas in the Sanzhao depression it is dominated by silicate mineral dissolution, evaporite dissolution (halite and gypsum), carbonate mineral dissolution/precipitation, and cation exchange. © 2005 Elsevier B.V. All rights reserved.
• Hanor, J. S., & McIntosh, J. C. (2006). Are secular variations in seawater chemistry reflected in the compositions of basinal brines?. Journal of Geochemical Exploration, 89(1-3 SPEC. ISS.), 153-156.
  More info

  Abstract: It has been proposed that brines in Phanerozoic sedimentary basins inherited their chemistries and salinities from evaporated paleoseawaters during times when the world oceans were Ca-rich and SO4-poor, such as the Silurian and Devonian. However, the compositions of typical Silurian and Devonian-hosted brines in the Illinois and Michigan basins show significant deviations from calculated Silurian seawater evaporation trends, reflecting instead, diagenetic control of compositions. In addition, brines in many basins show evidence for the dissolution of halite being an important source of salinity in addition to, or instead of, evaporated seawater. As long as there is halite present, generation of salinity could continue to occur long after the deposition of evaporites and the influx of evaporated seawater. Thus, even the concept of assigning an age to a basinal brine is problematic given the dynamics of fluid flow, mixing, and solute transport which can occur in sedimentary sequences. © 2006 Elsevier B.V. All rights reserved.
• McIntosh, J. C., & Walter, L. M. (2006). Paleowaters in Silurian-Devonian carbonate aquifers: Geochemical evolution of groundwater in the Great Lakes region since the Late Pleistocene. Geochimica et Cosmochimica Acta, 70(10), 2454-2479.
  More info

  Abstract: Changes in the climatic conditions during the Late Quaternary and Holocene greatly impacted the hydrology and geochemical evolution of groundwaters in the Great Lakes region. Increased hydraulic gradients from melting of kilometer-thick Pleistocene ice sheets reorganized regional-scale groundwater flow in Paleozoic aquifers in underlying intracratonic basins. Here, we present new elemental and isotopic analyses of 134 groundwaters from Silurian-Devonian carbonate and overlying glacial drift aquifers, along the margins of the Illinois and Michigan basins, to evaluate the paleohydrology, age distribution, and geochemical evolution of confined aquifer systems. This study significantly extends the spatial coverage of previously published groundwaters in carbonate and drift aquifers across the Midcontinent region, and extends into deeper portions of the Illinois and Michigan basins, focused on the freshwater-saline water mixing zones. In addition, the hydrogeochemical data from Silurian-Devonian aquifers were integrated with deeper basinal fluids, and brines in Upper Devonian black shales and underlying Cambrian-Ordovician aquifers to reveal a regionally extensive recharge system of Pleistocene-age waters in glaciated sedimentary basins. Elemental and isotope geochemistry of confined groundwaters in Silurian-Devonian carbonate and glacial drift aquifers show that they have been extensively altered by incongruent dissolution of carbonate minerals, dissolution of halite and anhydrite, cation exchange, microbial processes, and mixing with basinal brines. Carbon isotope values of dissolved inorganic carbon (DIC) range from -10 to -2‰, 87Sr/86Sr ratios range from 0.7080 to 0.7090, and δ 34 S s(-) SO4 values range from +10 to 30‰. A few waters have elevated δ13CDIC values (>15‰) from microbial methanogenesis in adjacent organic-rich Upper Devonian shales. Radiocarbon ages and δ18O and δD values of confined groundwaters indicate they originated as subglacial recharge beneath the Laurentide Ice Sheet (14-50 ka BP, -15 to -13‰ δ18O). These paleowaters are isolated from shallow flow systems in overlying glacial drift aquifers by lake-bed clays and/or shales. The presence of isotopically depleted waters in Paleozoic aquifers at relatively shallow depths illustrates the importance of continental glaciation on regional-scale groundwater flow. Modern groundwater flow in the Great Lakes region is primarily restricted to shallow unconfined glacial drift aquifers. Recharge waters in Silurian-Devonian and unconfined drift aquifers have δ18O values within the range of Holocene precipitation: -11 to -8‰ and -7 to -4.5‰ for northern Michigan and northern Indiana/Ohio, respectively. Carbon and Sr isotope systematics indicate shallow groundwaters evolved through congruent dissolution of carbonate minerals under open and closed system conditions (δ13CDIC = -14.7 to-11.1‰ and 87Sr/86Sr = 0.7080-0.7103). The distinct elemental and isotope geochemistry of Pleistocene- versus Holocene-age waters further confirms that surficial flow systems are out of contact with the deeper basinal-scale flow systems. These results provide improved understanding of the effects of past climate change on groundwater flow and geochemical processes, which are important for determining the sustainability of present-day water resources and stability of saline fluids in sedimentary basins. © 2006 Elsevier Inc. All rights reserved.
• McIntosh, J. C., Garven, G., & Hanor, J. (2006). Reorganization of basinal-scale groundwater flow and salinity gradients during Pleistocene glaciation: Hydrologic modeling study of the Michigan Basin, paper presented at Annual Meeting. Geol. Soc. of Am., Philadelphia, Pa.
• Kanduc, T., Pezdic, J., Vrabec, M., Zavsek, S., Ranzinger, M., Markic, M., McIntosh, J., & Walter, L. M. (2005). Tracing the carbon cycle using stable isotopes of carbon in the Pliocene lignite Velenje basin, Slovenia. Materials and Geoenvironment, 52(1), 67.
• McIntosh, J. C., & Walter, L. M. (2005). Volumetrically significant recharge of Pleistocene glacial meltwaters into epicratonic basins: Constraints imposed by solute mass balances. Chemical Geology, 222(3-4), 292-309.
  More info

  Abstract: Melting of kilometer-thick continental ice sheets, during Pleistocene glaciation, profoundly altered regional-scale groundwater flow in the low-lying stable interior of the North American craton. In this paper, we show that large volumes of glacial meltwater penetrated to great depths in underlying sedimentary basins through regionally extensive Silurian-Devonian carbonate aquifers, disrupting relatively stagnant saline fluids, and creating a strong disequilibrium pattern in fluid salinity. These dilute, isotopically light, meteoric waters migrated into overlying fractured, organic-rich Upper Devonian shales and significantly enhanced microbial methanogenesis, generating a unique class of natural gas deposits along the shallow basin margins. New data on formation water chemistry of Upper Devonian Antrim Shale gas wells along the northern and western margins of the Michigan Basin were integrated with previously published shale data and brines in subjacent Silurian-Devonian carbonates. This comprehensive database provides important constraints on fluid and solute transport, and makes a compelling case for the reorganization of drinking water resources and salinity structures along the shallow basin margins by Pleistocene glaciation. Na-Ca-Cl-Br relations and mass balance calculations were used to determine the relative volume of meteoric waters and sources of salinity in Antrim Shale fluids. The majority of shale formation waters contain greater than 50% meteoric water, with most containing over 80% meteoric water up to 300 m beneath the shale subcrop, despite the presence of a strong salinity gradient. Meteoric water recharge dissolved variable amounts of halite from evaporite-bearing Silurian-Devonian carbonates along the flow path into the shale and displaced highly saline NaCaCl remnant marine brines. The majority of Antrim Shale fluids owe greater than 60% of their salinity to halite dissolution, while less than 40% of Cl- is from mixing with brines in Silurian-Devonian strata. Oxygen and hydrogen isotope chemistry and Carbon-14 age dating indicate these NaCl brines were likely generated since the Late Pleistocene. Our conceptual model of fluid flow along the Michigan Basin margins and its role in generation of microbial gas were extrapolated to the larger glaciated Midcontinent region, where the Silurian-Devonian carbonate subcrop is continuous along the Illinois, Michigan, and Appalachian basin margins, and is overlain by Upper Devonian black shales. Major differences in the hydrostratigraphy and fluid salinity of the epicratonic basins controlled the extent of meteoric water invasion and generation of microbial methane. Increased hydraulic gradients from melting of the continental ice sheets greatly enhanced recharge of dilute waters into deep Silurian-Devonian aquifers and overlying fractured shales, reversing regional-scale groundwater flow and altering the major ion composition. These fluid migration events occurred over relatively short time scales (thousands of years), compared to well-documented basinal-scale fluid migration events driven by tectonics and sediment compaction (over millions of years). Understanding the hydrogeochemistry of the saline-meteoric water mixing zones and the sources of salinity in sedimentary basins are both important for constraining fluid and solute transport, chemical evolution of basinal fluids, and physical stability of brines during meteoric water invasion. © 2005 Elsevier B.V. All rights reserved.
• McIntosh, J., & Walter, L. (2005). Geochemical evolution of Pleistocene glacial meltwaters within regional carbonate aquifer systems, Midcontinent, US. Geochimica et Cosmochimica Acta Supplement, 69, A763.
• McIntosh, J. C., Walter, L. M., & Martini, A. M. (2004). Extensive microbial modification of formation water geochemistry: Case study from a Midcontinent sedimentary basin, United States. Geological Society of America Bulletin, 116(5-6), 743--759.
• Martini, A. M., Walter, L. M., Ku, T. C., Budai, J. M., McIntosh, J. C., & Schoell, M. (2003). Microbial production and modification of gases in sedimentary basins: A geochemical case study from a Devonian shale gas play, Michigan basin. AAPG Bulletin, 87(8), 1355-1375.
  More info

  Abstract: An expanded data set for gases produced from the Antrim Shale, a Devonian black shale in the Michigan basin, United States, has allowed for a detailed examination of the related chemical and isotopic compositional changes in the solid-gas-liquid systems that discriminate between microbial and thermogenic gas origin. In the Antrim Shale, economic microbial gas deposits are located near the basin margins where the shale has a relatively low thermal maturity and fresh water infiltrates the permeable fracture network. The most compelling evidence for microbial generation is the correlation between deuterium in methane and coproduced water. Along the basin margins, there is also a systematic enrichment in 13C of ethane and propane with decreasing concentrations that suggests microbial oxidation of these thermogenic gas components. Microbial oxidation accounts not only for the shift in δ13C values for ethane, but also, in part, for the geographic trend in gas composition as ethane and higher chain hydrocarbons are preferentially removed. This oxidation is likely an anaerobic process involving a syntrophic relationship between methanogens and sulfate-reducing bacteria. The results of this study are integrated into a predictive model for microbial gas exploration based on key geochemical indicators that are present in both gas and coproduced water. One unequivocal signature of microbial methanogenesis is the extremely positive carbon isotope values for both the dissolved inorganic carbon in the water and the coproduced CO2 gas. In contrast, the δ13C value of methane is of limited use in these reservoirs as the values typically fall between the commonly accepted fields for the thermogenic and microbial gas. In addition, the confounding isotopic and compositional overprint of microbial oxidation, increasing the 13CC1,C2,C3 values to typically thermogenic values, may obscure the distinction between methanogenic and thermogenic gas.
• McIntosh, J. C., Walter, L. M., & Martini, A. M. (2002). Pleistocene recharge to midcontinent basins: Effects on salinity structure and microbial gas generation. Geochimica et Cosmochimica Acta, 66(10), 1681-1700.
  More info

  Abstract: The hydrogeochemistry of saline-meteoric water interface zones in sedimentary basins is important in constraining the fluid migration history, chemical evolution of basinal brines, and physical stability of saline formation waters during episodes of freshwater recharge. This is especially germane for interior cratonic basins, such as the Michigan and Illinois basins. Although there are large differences in formation water salinity and hydrostratigraphy in these basins, both are relatively quiescent tectonically and have experienced repeated cycles of glaciation during the Pleistocene. Exploration for unconventional microbial gas deposits, which began in the upper Devonian-age Antrim Shale at the northern margin of the Michigan Basin, has recently extended into the age-equivalent New Albany Shale of the neighboring Illinois Basin, providing access to heretofore unavailable fluid samples. These reveal an extensive regional recharge system that has profoundly changed the salinity structure and induced significant biogeochemical modification of formation water elemental and isotope geochemistry. New-formation water and gas samples were obtained from Devonian-Mississippian strata in the Illinois Basin. These included exploration wells in the New Albany Shale, an organic-rich black shale of upper Devonian age, and formation waters from over- and underlying regional aquifer systems (Siluro-Devonian and Mississippian age). The hydrostratigraphic relations of major aquifers and aquitards along the eastern margin of the Illinois Basin critically influenced fluid migration into the New Albany Shale. The New Albany Shale formation water chemistry indicates significant invasion of meteoric water, with δD values as low as -46.05‰, into the shale. The carbon stable isotope system (δ13C values as high as 29.4‰), coupled with δ18O, δD, and alkalinity of formation waters (alkalinity ≤24.08 meq/kg), identifies the presence of microbial gas associated with meteoric recharge. Regional geochemical patterns identify the underlying Siluro-Devonian carbonate aquifer system as the major conduit for freshwater recharge into the fractured New Albany Shale reservoirs. Recharge from overlying Mississippian carbonates is only significant in the southernmost portion of the basin margin where carbonates directly overlie the New Albany Shale. Recharge of dilute waters (CI-

Proceedings Publications

• Edwards, C., Stamenkovic, V., Boston, P., Lynch, K., Tarnas, J., Sherwood-Lollar, B., Atreya, S., Templeton, A., Freeman, A., Fischer, W., Spohn, T., Webster, C., Fairén, A. G., Mustard, J. (., Mischna, M., Onstott, T. C., Osburn, M. R., Kieft, T., Grimm, R. E., , Brinckerhoff, W. B., et al. (2021, 2021/05/1). Deep Trek: Mission Concepts for Exploring Subsurface Habitability & Life on Mars — A Window into Subsurface Life in the Solar System. In Bulletin of the American Astronomical Society, 53, 321.
• Ashley, K., Davis, K., Martini, A., Fields, M., & Mcintosh, J. C. (2017, August). Deuterium as a Quantitative Tracer of Enhanced Microbial Coalbed Methane Production. In Goldschmidt Conference, Geochemical Society.
• Chorover, J. D., Brooks, P., Gallery, R. E., Mcintosh, J. C., Olshansky, Y., & Rasmussen, C. (2017, December). Biogeochemical control points in a water‐limited critical zone. In AGU Fall Meeting.
• Dwivedi, R., Meixner, T., Mcintosh, J. C., Ferre, P. A., Eastoe, C. J., Minor, R., Barron-Gafford, G. A., & Chorover, J. D. (2017, December). Hydrologic functioning of the deep Critical Zone and contributions to streamflow in a high elevation catchment: testing of multiple conceptual models. In AGU Fall Meeting.
• Mcintosh, J. C., White, A. M., Moravec, B. G., & Chorover, J. D. (2017, August). Changing Water, Carbon and Energy Fluxes Alters Deep CZ Structure and Solute Exports to Streams. In Goldschmidt Conference, Geochemical Society.
• Olshansky, Y., White, A. M., Thompson, M., Moravec, B. G., Mcintosh, J. C., & Chorover, J. D. (2017, December). Evolution of concentration‐discharge relations revealed by high frequency diurnal sampling of stream water during spring snowmelt. In AGU Fall Meeting.
• Sanchez, A., Meixner, T., Mcintosh, J. C., & Chorover, J. D. (2017, December). Impact of Wildfire on Solute Release in Forested Catchments, Jemez River, New Mexico, USA. In AGU Fall Meeting.
• Schweitzer, H., Ritter, D., Barnhart, E., Cunningham, A., Gerlach, R., Mcintosh, J. C., & Fields, M. (2017, November). Aqueous Sulfate Levels Control Methanogen Diversity and Activity in Subsurface Coal Seams. In The International Society of Subsurface Microbiology.
• White, A. M., Moravec, B. G., Mcintosh, J. C., & Chorover, J. D. (2017, August). Hydrologic and Environmental Controls on Uranium-Series Isotopes in a Natural Volcanic Weathering Environment. In Goldschmidt Conference, Geochemical Society.
• White, A. M., Moravec, B. G., Mcintosh, J. C., & Chorover, J. D. (2017, December). Hydrologic and environmental controls on uranium‐series and strontium isotope ratios in a natural weathering environment. In AGU Fall Meeting.
• Earll, M., Barnhart, E., Ritter, D., Vinson, D., Orem, W., Vengosh, A., & McIntosh, J. (2015). Source and Cycling of Trace Metals and Nutrients in a Microbial Coalbed Methane System. In AGU Fall Meeting Abstracts.
• Garcia, S., Nyachoti, S., Ma, L., Szynkiewicz, A., & McIntosh, J. (2015). Tracing Anthropogenic Salinity Inputs to the Semi-arid Rio Grande River: A Multi-isotope Tracer (U, S, B and Sr) Approach. In AGU Fall Meeting Abstracts.
• Kanduc, T., Grassa, F., Lazar, J., Jamnikar, S., Zavsek, S., & McIntosh, J. (2014). Bioconversion of Coal: Hydrologic indicators of the extent of coal biodegradation under different redox conditions and coal maturity, Velenje Basin case study, Slovenia. In EGU General Assembly Conference Abstracts, 16.
• Nyachoti, S., Ma, L., Szynkiewicz, A., Jin, L., & McIntosh, J. (2014). U and Sr Isotope Tracers of Agricultural Salinity Sources to the Lower Rio Grande River. In AGU Fall Meeting Abstracts, 1.
• Shelton, J., McIntosh, J., Warwick, P., & McCray, J. (2014). Geospatial Hydrochemical and Microbiological Implications on the Occurrence of Crude Oil Biodegradation and Methanogenesis. In AGU Fall Meeting Abstracts, 1.
• White, A., McIntosh, J., Meixner, T., Brooks, P., & Chorover, J. (2014). Impacts of Wildfire on Throughfall and Stemflow Precipitation Chemistry. In AGU Fall Meeting Abstracts, 1.
• Zapata-Rios, X., Brooks, P., Troch, P., & McIntosh, J. (2014). Co-evolution of Climate, Soil, and Vegetation and their interplay with Hydrological Partitioning at the Catchment Scale. In AGU Fall Meeting Abstracts, 1.
• Brooks, P., Biederman, J., Condon, K., Chorover, J., McIntosh, J., Meixner, T., & Perdrial, J. (2013). A cross-site comparison of factors controlling streamwater carbon flux in western North American catchments. In AGU Fall Meeting Abstracts.
• Chorover, J., Perdrial, J., Field, J., Pelletier, J., Pohlmann, M., Losleben, M., Lasharr, K., Amistadi, M., Brooks, P., McIntosh, J., & others, . (2013). Fluid Chemistry Dynamics Before and After Fire in the Jemez River Basin Critical Zone Observatory. In AGU Fall Meeting Abstracts.
• Guido, Z., McIntosh, J., & Papuga, S. (2013). Constraining Glacial Runoff Contributions to Water Resources in the Cordillera Real, Bolivia using Environmental Tracers. In AGU Fall Meeting Abstracts.
• Lohse, K., Gallo, E., Brooks, P., Meixner, T., & McIntosh, J. (2013). Tradeoffs of modifications of storm water managements systems for nitrogen loss pathways in semi-arid ecosystems. In AGU Fall Meeting Abstracts.
• Ma, L., Szynkiewicz, A., Borrok, D., & McIntosh, J. C. (2013, Spring). Using Uranium Isotopes to Determine Salinity Sources in Rio Grande Waters. In NEW MEXICO GEOLOGICAL SOCIETY 2013 SPRING MEETING.
• Meixner, T., Michalski, G., Dejwahk, N., Riha, K., Lohse, K., Gallo, E., McIntosh, J., & Brooks, P. (2013). Insights on Biogeochemistry from the Triple Isotope System of Nitrate. In AGU Fall Meeting Abstracts.
• VINSON, D. S., MCINTOSH, J. C., DWYER, G. S., WARNER, N. R., & VENGOSH, A. (2013). Boron desorption and boron isotopes in sodium bicarbonate coalbed methane waters. In 2013 GSA Annual Meeting in Denver.
• Vinson, D., McIntosh, J., Blair, N., & Martini, A. (2013). Re-assessing H and C Isotope Signatures of Biogenic Methane in Coalbeds and Shales: Metabolic Pathways and Alternative Influences. In AGU Fall Meeting Abstracts.
• Harpold, A., Brooks, P., Perdrial, J., McIntosh, J., Meixner, T., Zapata, X., & Chorover, J. (2012). Quantifying Variation in Solute Sources and Nutrient Cycling in Montane Headwater Catchments. In AGU Fall Meeting Abstracts, 1.
• Huckle, D., Ma, L., McIntosh, J., Rasmussen, C., & Chorover, J. (2012). Using Uranium-series Isotopes to Trace Water Sources to Streamflow and Estimate Soil Formation Rates in a Semiarid Montane Catchment. In AGU Fall Meeting Abstracts, 1.
• McIntosh, J. C. (2012). Geochemical and isotopic composition of Appalachian Basin brines: origin of salinity and fingerprints of fluid reservoirs. In 2012 GSA Annual Meeting in Charlotte.
• PERDRIAL, J. N., VAZQUEZ-ORTEGA, A., MCINTOSH, J., HARPOLD, A., PORTER, C., ZAPATA-RIOS, X., GUTHRIDGE, L., BROOKS, P. D., & CHOROVER, J. (2012). STREAM WATER ORGANIC MATTER CHARACTERISTICS BEFORE AND AFTER THE LAS CONCHAS WILDFIRE IN NM. In Geological Society of America Abstracts with Programs,, 44.
• Perdrial, J., Rasmussen, C., McIntosh, J., Zapata, X., Harpold, A., Vazquez, A., Porter, C., Brooks, P., Meixner, T., Mitra, B., & others, . (2012). Carbon and water, the energy for weathering and chemical denudation. In AGU Fall Meeting Abstracts, 1.
• Porter, C., McIntosh, J., Derry, L. A., Meixner, T., Chorover, J., Brooks, P., Rasmussen, C., & Perdrial, J. N. (2012). Determining solute inputs to soil and stream waters in a seasonally snow-covered mountain catchment in northern New Mexico using Ge/Si, 87Sr/86Sr and ion chemistry. In AGU Fall Meeting Abstracts, 1.
• Shelton, J., McIntosh, J., Warwick, P., Vinson, D., & Lee Zhi Yi, A. (2012). The fate of carbon dioxide injected into a coal-bearing formation. In AGU Fall Meeting Abstracts, 1.
• Vazquez, A., Perdrial, J., Harpold, A., Zapata, X., Rasmussen, C., McIntosh, J., Schaap, M., Pelletier, J., Amistadi, M., & Chorover, J. (2012). Rare earth elements as reactive tracers of biogeochemical weathering in the Jemez River Basin Critical Zone Observatory. In AGU Fall Meeting Abstracts, 1.
• Vinson, D. S., McIntosh, J. C., Ritter, D. J., Blair, N. E., & Martini, A. M. (2012). Carbon isotope modeling of methanogenic coal biodegradation: Metabolic pathways, mass balance, and the role of sulfate reduction, Powder River Basin, USA. In Geological Society of America Abstracts with Programs, 44.
• Zapata, X., Troch, P., McIntosh, J., Broxton, P., & Brooks, P. (2012). The Effect of Terrain Aspect on Interannual Variability of Hydrologic Response in Mountainous Catchments in New Mexico. In AGU Fall Meeting Abstracts, 1.
• Zapata-Rios, X., Troch, P., Broxton, P., McIntosh, J., Harman, C., Harpold, A., & Brooks, P. D. (2012). Water storage dynamics in high elevation semi-arid catchments. In Geol Soc Am Abstr progr, 44.
• Brooks, P., Litvak, M., Harpold, A., Molotch, N., McIntosh, J., Troch, P., & Zapata, X. (2011). Non-linear feedbacks between climate change, hydrologic partitioning, plant available water, and carbon cycling in montane forests. In AGU Fall Meeting Abstracts, 1.
• Chorover, J., Troch, P., Pelletier, J., Rasmussen, C., Brooks, P., McIntosh, J., Breshears, D., Huxman, T., Papuga, S., Lohse, K., & others, . (2011). Carbon, water and weathering limitations in the semi-arid critical zone. In AGU Fall Meeting Abstracts, 1.
• Dannemann, F., Zapata, X., McIntosh, J., Perdrial, J., Brooks, P., Chorover, J., Lohse, K., & Fricke, H. (2011). Temporal and spatial dynamics of carbon and nitrogen in headwater snow-dominated catchments, Jemez Mountains, New Mexico. In AGU Fall Meeting Abstracts, 1.
• Driscoll, J., Meixner, T., Molotch, N., Sickman, J., Williams, M., McIntosh, J., & Brooks, P. (2011). Inverse geochemical reaction path modelling and the impact of climate change on hydrologic structure in snowmelt-dominated catchments in the Southwestern USA. In AGU Fall Meeting Abstracts, 1.
• Lohse, K., Gallo, E., Carlson, M., Riha, K., Brooks, P., McIntosh, J., Sorooshian, A., Michalski, G., & Meixner, T. (2011). Impacts of urbanization on nitrogen cycling and aerosol, surface and groundwater transport in semi-arid regions. In AGU Fall Meeting Abstracts, 1.
• Zapata, X., McIntosh, J., Sorooshian, A., Lohse, K., Brooks, P., Troch, P., Chorover, J., & Heidbuechel, I. (2011). Sources and amounts of Nitrogen Deposited in Sky-Island Ecosystems. In AGU Fall Meeting Abstracts, 1.
• Damashek, J., Miller, S. E., Kirk, M. F., McIntosh, J. C., Schlegel, M. E., Petsch, S. T., & Martini, A. M. (2010). Microbial community structure and geochemistry of the New Albany Shale (Illinois Basin) and its potential to produce biogenic methane. In GEOCHIMICA ET COSMOCHIMICA ACTA, 74.
• Guido, Z., McIntosh, J., & Papuga, S. (2010). Changing Precipitation Patterns or Waning Glaciers? Identifying Water Supply Vulnerabilities to Climate Change in the Bolivian Andes. In AGU Fall Meeting Abstracts.
• McIntosh, J., Bates, B., Schlegel, M., & Martini, A. (2010). C and H isotope systematics of microbial methane accumulations in coalbeds and fractured shales. In GEOCHIMICA ET COSMOCHIMICA ACTA, 74.
• Miller, S. E., Damashek, J., Martini, A. M., Schlegel, M. E., McIntosh, J. C., & Kirk, M. F. (2010). New Albany Shale Microbiology and Geochemistry: Characterization of and Geochemical Constraints on Methane Generating Microbial Communities. In Geological Society of America Abstracts with Programs,, 42.
• Pelletier, J., Rasmussen, C., Breshears, D., Brooks, P., Chorover, J., Huxman, T., Lohse, K., Meixner, T., McIntosh, J., Kurc, S., & others, . (2010). Coevolution of topography, hydrology, soil development, and vegetation in sky islands of the southwestern United States. In AGU Fall Meeting Abstracts.
• Perdrial, J., McIntosh, J., Brooks, P., & Chorover, J. (2010). DOM as a potential tracer for in-stream processes in small mountain catchments (JRB-SCM Critical Zone Observatory). In AGU Fall Meeting Abstracts.
• Person, M., Banerjee, A., McIntosh, J., Schlegel, M., Gable, C., Cohen, D., & Rupp, J. (2010). Ice-Sheet Aquifer Interactions within the midcontinent, USA: Implications for CO2 Sequestration. In AGU Fall Meeting Abstracts.
• Ray, J., McIntosh, J., Perdrial, J., Brooks, P., Chorover, J., Rasmussen, C., & Meixner, T. (2010). Sources and Cycling of Carbon in Two Semi-Arid Catchments, Valles Caldera Preserve, NM: Insights From Carbon Isotopes. In AGU Fall Meeting Abstracts.
• Schlegel, M. E., McIntosh, J. C., Bates, B. L., Kirk, M. F., & Martini, A. M. (2010). Methanogen variations related to hydrogeochemical conditions in organic-rich shales and coals in the Illinois Basin, USA. In GEOCHIMICA ET COSMOCHIMICA ACTA, 74.
• Vinson, D., Mcintosh, J., & Vengosh, A. (2010). Sr isotope constraints on natural oxy-anionic contaminants in a basin-fill aquifer (Arizona, USA). In GEOCHIMICA ET COSMOCHIMICA ACTA, 74.
• Driscoll, J., Meixner, T., Brooks, P., McIntosh, J., Williams, M., Molotch, N., & Sickman, J. (2009). Using an Inverse Geochemical Reaction Path Model to Analyze the Effects of Climate Change on High-elevation Catchments in the Southern Rocky Mountains. In AGU Fall Meeting Abstracts, 1.
• Jardine, A., Troch, P., Chorover, J., Rasmussen, C., McIntosh, J., & Huxman, T. (2009). Dynamics of natural system hillslope silicate weathering: coupling water transit time with REYs in solution. In AGU Fall Meeting Abstracts, 1.
• MCINTOSH, J. C., BROWN, K. B., BAKER, V. R., & GOSCH, D. (2009). ISOTOPIC EVIDENCE FOR RECHARGE OF LATE PLEISTOCENE MISSOULA FLOODWATERS INTO THE COLUMBIA RIVER BASALT AQUIFERS. In 2009 Portland GSA Annual Meeting.
• Adkins, C., McIntosh, J., Eastoe, C., & Dickinson, J. (2008). Use of Chemical and Isotopic Tracers for Estimating Ground-Water Recharge, Flow Paths, and Residence Times in the Middle San Pedro Basin, Southeast Arizona. In AGU Fall Meeting Abstracts.
• Bates, B., & McIntosh, J. (2008). Effects of groundwater recharge rates and nutrient supply on metabolic pathways for coal bed methane generation in the Powder River Basin. In AGU Fall Meeting Abstracts.
• Brown, K., McIntosh, J., Rademacher, L., Lohse, K., & Gosch, D. (2008). A Multi-Tracer Approach to Determine the Impacts of Agricultural Irrigation Recharge on Groundwater Sustainability in the Columbia Plateau Basalt Aquifers, Central Washington, USA. In AGU Fall Meeting Abstracts, 1.
• Gallo, E., Brooks, P., Lohse, K., McIntosh, J., McLain, J., & Meixner, T. (2008). Solute Sourcing and Hydrologic Response to Monsoon Precipitation Along a Gradient of Urban Land Use. In AGU Fall Meeting Abstracts.
• McIntosh, J., Osborn, S., & Grasby, S. (2008). Subglacial recharge into carbonate bedrock aquifers and generation of microbial methane in adjacent organic-rich shales: southwestern Ontario, Canada. In AGU Fall Meeting Abstracts.
• Osborn, S., & McIntosh, J. (2008). Iodine-129 of Appalachian Basin Brines: Implications for Microbial Fractionation and Fluid Migration. In 2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM.
• Schlegel, M., Bates, B., & McIntosh, J. (2008). Activity and Extent of Carbon Dioxide and Acetate Utilizing Methanogens in Deep Organic-rich Aquifers Within the Illinois Basin, USA. In AGU Fall Meeting Abstracts, 1.
• Dejwakh, N., Meixner, T., & McIntosh, J. (2007). Sources of Nitrate to Tucson, Arizona Groundwaters.. In AGU Fall Meeting Abstracts.
• Gallo, E., Snyder, M., Dejwakh, N., Lohse, K., Brooks, P., McLain, J., McIntosh, J., & Meixner, T. (2007). Quantifying Land Use and Land Cover Effects on Urban Runoff Water Quality.. In AGU Fall Meeting Abstracts, 1.
• McIntosh, J., Petsch, S., Schlegel, M., & Osborn, S. (2007). Paleohydrologic controls on methanogenesis in organic-rich saline aquifers. In AGU Fall Meeting Abstracts.
• Warwick, P., Hook, R., Clark, A., Corum, M., McIntosh, J., Burr, C., Hackley, P., & Jensen, D. (2007, Fall). Coal bed methane exploration in Zavala County, Texas. In Abstr. Ann. Conv. Am. Assoc. Petrol. Geol. American Association of Petroleum Geologists, Tulsa, OK. http://www. searchanddiscovery. net/abstracts/html/2007/annual/abstracts/lbWarwick. htm, 147.
• MCINTOSH, J. C. (2005). IMPACT OF PLEISTOCENE GLACIATION ON FLUID AND SOLUTE TRANSPORT IN INTRACRATONIC SEDIMENTARY BASINS: INTEGRATIVE STUDY OF FORMATION WATER GEOCHEMISTRY AND NUMERICAL MODELING. In 2005 Salt Lake City Annual Meeting.
• McIntosh, J., Garven, G., & Hanor, J. (2005). Modeling variable-density fluid flow and solute transport in glaciated sedimentary basins. In AGU Fall Meeting Abstracts.
• MCINTOSH, J. C. (2004). HYDROGEOCHEMICAL CONSTRAINTS ON PLEISTOCENE GLACIAL MELTWATER INVASION INTO MIDCONTINENT, US REGIONAL AQUIFER SYSTEMS: IMPACT ON SALINITY STRUCTURE AND GENERATION OF MICROBIAL GAS. In 2004 Denver Annual Meeting.
• SZRAMEK, K., WILLIAMS, E., MCINTOSH, J., KANDUC, T., OGRINC, N., & WALTER, L. M. (2004). CARBONATE WEATHERING AND DIC FLUXES IN CARBONATE-BEARING LANDSCAPES, MICHIGAN AND SLOVENIA. In 2004 Denver Annual Meeting.
• MCINTOSH, J. C. (2003, Fall). IMPACT OF PLEISTOCENE GLACIATION ON THE HYDROGEOCHEMISTRY OF MID CONTINENT SEDIMENTARY BASINS. In 2003 GSA Annual Meeting, Seattle, WA.
• Martini, A. M., Petsch, S. T., Nuesslein, K., & McIntosh, J. (2003). Active Microbial Methane Production and Organic Matter Degradation in a Devonian Black Shale. In AGU Fall Meeting Abstracts, 1.
• MCINTOSH, J. C., WALTER, L. M., & MARTINI, A. M. (2002). COMPARATIVE STUDY OF THE EFFECT OF PLEISTOCENE RECHARGE ON FORMATION WATER GEOCHEMISTRY IN THE ILLINOIS VS. MICHIGAN BASINS. In 2002 Denver Annual Meeting.
• MCINTOSH, J. C., WALTER, L. M., & MARTINI, A. M. (2001). MAJOR GEOCHEMICAL MODIFICATION OF FORMATION WATERS ALONG SEDIMENTARY BASIN MARGINS: ROLE OF MICROBIAL METHANOGENESIS. In GSA Annual Meeting, November 5-8, 2001.
• Martini, A., Walter, L., & McIntosh, J. (2001). Hydrocarbon Oxidation in Sedimentary Basin Gas Reservoirs. In Eleventh Annual VM Goldschmidt Conference.
• Martini, A., Walter, L., McIntosh, J., & Budai, J. (1999). Identification of Microbial Methane Deposits Via Core Analysis. In Ninth Annual VM Goldschmidt Conference.
• McIntosh, J., Walter, L., Budai, J., & Martini, A. (1999). Chemical and Isotopic Evidence for Pleistocene Recharge to Silurian-Devonian Aquifers, Illinois Basin. In Ninth Annual VM Goldschmidt Conference.

Presentations

• Seltzer, A. M., Ng, J., Kulongoski, J., Stute, M., Severinghaus, J. P., Danskin, W. R., Gannon, R., Stolp, B. J., Tyne, R. L., Johnson, H. M., Noyes, C., Mcintosh, J. C., Ferguson, G., Bourg, I. C., & Shackleton, S. A. (2022, Summer). New noble gas isotope tracers for groundwater hydrology. Goldschmidt2022. Hawaii.
• Ferguson, G., & Mcintosh, J. C. (2021, April). Renewed thinking on groundwater age. EGU.
• Kim, J., Ferguson, G., Person, M., Jiang, W., Lu, Z., Yang, G., Tyne, R., Ballentine, C., Reiners, P. W., & Mcintosh, J. C. (2021, December). Krypton isotopes constrain timing of regional meteoric circulation enhanced by rapid denudation. AGU Fall Meeting.
• Mcintosh, J. C. (2021). Geochemical evolution of deep groundwater flow systems over geologic timescales. Seminar at University of Iowa, Department of Earth and Environmental Sciences.
• Mcintosh, J. C. (2021, Fall). Geologic evolution of groundwater flow systems & implications for subsurface microbial life. University of Arizona, Department of Geosciences.
• Mcintosh, J. C. (2021, February). Competition for shrinking groundwater resources. University of Arizona, Environmental Breakfast Club.
• Mcintosh, J. C., Markovich, K., Noyes, C., Lotter, L. E., Ferguson, G., Carroll, K., & Purtschert, R. (2021, July). Application of 85Kr, 3H, 39Ar, and 14C, noble gas thermometry, and modeling to constrain mountain front recharge to basin-fill aquifers. Goldschmidt Virtual Conference.
• Noyes, C., Ferguson, G., Carroll, K., Purtschert, R., & Mcintosh, J. C. (2021, December). Using Argon-39, noble gases, and other environmental tracers to infer changes in recharge to the semi-arid Tucson Basin (Arizona, USA) over the Holocene. AGU Fall Meeting.
• Tyne, R., Barry, P., Cheng, A., Kim, J., Hillegonds, D., Mcintosh, J. C., & Ballentine, C. (2021, July). Understanding the role of basin architecture on the geochemical evolution of fluids in the Paradox Basin using noble gases. Goldschmidt Virtual Conference.
• Mcintosh, J. C. (2019, December). Invited presentation: "Earth's hidden hydrogeosphere: distribution, evolution, and circulation of meteoric waters at depth in the earth's crust through Critical Zone. AGU Fall Meeting. San Francisco: AGU.
• Dwivedi, R., Meixner, T., Mcintosh, J. C., Ferre, P. A., Eastoe, C., Castro, C. L., Wright, W., Niu, G., Minor, R., Knowles, J., Barron-Gafford, G. A., Abramson, N., Mitra, B., Stanley, M., & Chorover, J. D. (2018, Fall). An improved and practical approach for estimating catchment-scale response functions through power spectral analysis. American Geophysical Union Fall Meeting. Washington DC.
• Kanduc, T., Slejkovec, Z., Vreca, P., Samardzija, Z., Vrabec, M., Vrabec, M., Verbovsek, T., Jamnikar, S., Bozic, D., Lenart, M., Solomon, D. K., Mcintosh, J. C., & Grassa, F. (2018, Fall). BIOGEOCHEMICAL CHARACTERIZATION OF DIFFERENT GEOLOGICAL MEDIA (COALBED GASES, GROUNDWATER, LIGNITE) FROM VELENJE COAL BASIN. SLOVENSKI GEOLOŠKI KONGRES. Slovenia.
• Mcintosh, J. C. (2018, August). Earth 4D – Subsurface Science and Exploration Workshop. CIFAR (Canadian Institute for Advanced Research), invited international participant. Toronto, Ontario, Canada.
• Mcintosh, J. C. (2018, Fall). Human impacts on deep terrestrial water cycle. Global Institute for Water Security, Distinguished Lecture Series. University of Saskatchewan.
• Mcintosh, J. C., & Ferguson, G. (2018, Fall). Large-scale changes in subsurface water budgets from oil and gas production. American Geophysical Union Fall Meeting. Washington DC.
• Moravec, B., White, A., Root, R. A., Mcintosh, J. C., & Chorover, J. D. (2018, Fall). DECONVOLVING LEGACY AND CONTEMPORANEOUS WEATHERING IN A PORPHYRITIC RHYOLITE AND RHYOLITIC TUFF DOMINATED UPLAND CATCHMENT, VALLES CALDERA, NEW MEXICO. Geological Society of America Conference. Indianapolis, IN.
• Sanchez, R. A., Meixner, T., Mcintosh, J. C., & Chorover, J. D. (2018, Fall). Impact of wildfire on solute fluxes in forested catchments, Jemez River Basin, New Mexico, USA. American Geophysical Union Fall Meeting. Washington DC.
• Shelton, J., Andrews, R., Akob, D., DeVera, C., Mumford, A., Mcintosh, J. C., & McCray, J. (2018, Spring). Examining the impact of a CO2-enhanced oil recovery flood on the microbial community in the target oil and gas reservoir. American Society for Microbiology Conference. Rhode Island.
• White, A., Ma, L., Moravec, B., Mcintosh, J. C., & Chorover, J. D. (2018, August). Combining U-Series and Sr isotopes to trace water flow through the Critical Zone. Goldschmidt Conference. Boston, MA: Geochemical Society.
• White, A., Moravec, B., Olshansky, Y., Sanchez, A., Ferre, P. A., Meixner, T., Mcintosh, J. C., & Chorover, J. D. (2018, Fall). THE INFLUENCE OF CRITICAL ZONE STRUCTURE ON ITS HYDROLOGIC FUNCTION: INSIGHTS INTO THE STORAGE AND ROUTING OF WATER THROUGH THE CRITICAL ZONE. Geological Society of America Conference. Indianapolis, IN.
• Mcintosh, J. C. (2017, April). Tracing environmental impacts of hydraulic fracturing and oil/gas production. University of Utah, Global Change and Sustainability Center, Invited Colloqium Speaker.
• Mcintosh, J. C. (2017, August). Changing water, carbon and energy fluxes alters deep CZ structure and solute exports to streams. Goldschmidt Meeting, Geochemical Society. Paris, France.
• Mcintosh, J. C. (2017, January). Isotopic tracers of environmental impacts of hydraulic fracturing and shale gas production. Geosciences Department Seminar, University of Arizona.
• Bryan, M., Alyssa, W., Ben, P., Andres, S., Dawson, F., Mcintosh, J. C., Pelletier, J. D., Gallery, R. E., Rasmussen, C., & Chorover, J. D. (2016, Winter). Coring the deep Critical Zone in the Jemez River Basin Critical Zone. 2016 American Geophysical Union Annual Meeting. San Francisco CA: American Geophysical Union.
• Dwivedi, R., Meixner, T., Mcintosh, J. C., Ferre, P. A., & Chorover, J. D. (2016, Fall). A multi-tracer approach coupled to numerical models to improve understanding of mountain block processes in a high elevation, semi-humid catchment. Geological Society of America (GSA) Annual Meeting. Denver, CO.
• Ma, L., Garcia, S., Nyachoti, S., Szynkiewicz, A., Mcintosh, J. C., & Gaillardet, J. (2016, Summer). Salinity Sources in the Semi-Arid Rio Grande River with a Multi-Isotope Tracer (U, S, B, and Sr) Approach. 26th Goldschmidt Conference. Yokohama, Japan: Geochemical Society.
• Mcintosh, J. C. (2016, Fall). Tracers of fugitive gas and fluids in the environment: impacts of oil/gas production. International Atomic Energy Agency (IAEA) Technical Meeting on Isotope Techniques to Assess Impact of Hydraulic Fracturing (Fracking) on Groundwater. Vienna, Austria.
• Mcintosh, J. C. (2016, Spring). Geochemical and microbial tracers of natural gas formation and transport in the environment. Colorado School of Mines, Van Tuyl lecture series, Geology and Geological Engineering department.
• Mcintosh, J. C., Xavier, Z., Rasmussen, C., Paul, B. D., Gallery, R. E., Pelletier, J. D., & Chorover, J. D. (2016, Winter). Changing Energy Inputs at Earth’s Surface Translates to Differences in Water Availability, Weathering Rates, and Biotic Activity at Depth. 2016 American Geophysical Union Annual Meeting, Union Session. San Francisco CA: American Geophysical Union.
• Shelton, J., McIntosh, J., Akob, D., Spear, J., Warwick, P., & McCray, J. (2016, Spring). Hydrobiogeochemical controls on a low-carbon emitting energy extraction mechanism: exploring methanogenic crude oil biodegradation. EGU General Assembly Conference Abstracts.
• Mcintosh, J. C. (2015, January). Hydrogeochemical insights into water-energy issues: application of chemical and isotopic tracers. HWR Department Seminar Series.
• Jull, A. J., Chang, C., Biddulph, D., Tritz, C., Mcintosh, J. C., Priyardashi, A., Thiemens, M., Burr, G. S., & Russell, J. L. (2014, August). Environmental Iodine-129 studies at the University of Arizona. 13th International Conference on Accelerator Mass Spectrometry. Aix-en-Provence, France: AMS-13 Conference.
• Mcintosh, J. C. (2014, Fall). Impact of continental glaciation on water and energy resources. Montana State University, Department of Earth Sciences Colloquium.
• Mcintosh, J. C. (2014, Fall). Impacts of Pleistocene glaciation on hydrobiogeochemical processes in sedimentary basins. Geological Society of America Annual Meeting.
• Mcintosh, J. C. (2014, October). Isotopic indicators of microbial carbon cycling in subsurface reservoirs. Montana State University, Center for Biofilm Engineering.
• Mcintosh, J. C. (2014, October). Isotopic indicators of microbial carbon cycling in subsurface reservoirs. United States Geological Survey, Montana/Wyoming Water Sciences Center, Helena, MT.
• Mcintosh, J. C. (2014, October). Sources and distribution of salinity in hydrocarbon-associated fluids in sedimentary basins. Geological Society of America Pardee Symposium on “Energy Resource Development and Groundwater: Looking Broader and Deeper”.
• Mcintosh, J. C. (2013, Spring). Deep biosphere: influence of hydrology on microbial cycling and methane generation. Soil, Water, and Environmental Science Department Colloqium.

Poster Presentations

• Mcintosh, J. C. (2014, Summer). Groundwater extraction for coal bed methane production: influence on the subsurface geochemical environment. 21st V.M. Goldschmidt Conference.
• Breshears, D. D., Field, J. P., Law, D. J., Brooks, P. D., Chorover, J. D., Pelletier, J. D., Troch, P. A., Lopez Hoffman, L. -., Rasmussen, C. -., Papuga, S. A., Barron-Gafford, G. A., Mcintosh, J. C., Harpold, A., Biederman, J. A., & Litvak, M. (2013, October 2013). Bridging from soil to ecosystem goods and services provided by the Critical Zone. AGU Chapman Conference: Soil-mediated drivers of coupled biogeochemical and hydrological processes across scales. Tucson.

Reviews

• Lohse, K. A., Brooks, P. D., McIntosh, J. C., Meixner, T., & Huxman, T. E. (2009. Interactions Between Biogeochemistry and Hydrologic Systems(pp 65-96).
  More info

  Here we review the fundamental interactions between hydrology and the cycling of carbon (C) and nitrogen (N) in terrestrial and stream ecosystems. We organize this review around five commonly studied environments: land-atmosphere interface, soil, groundwater, streams, and headwater catchments. Common among all environments is that hydrological transitions, either episodic changes in water availability or hydrologic transport of reactants, result in disproportionately high rates of C and N cycling. Two major research challenges in coupling hydrological and biogeochemical research are (a) effectively scaling reactions at these spatiotemporal transitions and (b) combining the progress made within each of the five environments listed above into an integrated understanding of hydrobiogeochemical cycles. Changes in local-to-regional hydrological cycling are likely to result in unexpected surprises at the landscape scale until progress in these research areas is made.

Creative Productions

• Mcintosh, J. C. (2019. The global race for groundwater speeds up. The Conversation (Canada)The Conversation is an independent source of news and views, from the academic and research community, delivered direct to the public.. https://theconversation.com/the-global-race-for-groundwater-speeds-up-to-feed-agricultures-growing-needs-108458

Others

• Mcintosh, J. C. (2017, February). Cienega watershed study to add data to Rosemont debate. Arizona Daily Star. http://tucson.com/news/local/cienega-watershed-study-to-add-data-to-rosemont-debate/article_cf84e74a-0f03-5e14-9899-c8455373d8a6.html
• McIntosh, J. C. (2004). Impact of Pleistocene glaciation on midcontinent sedimentary basin fluids: Reorganization of salinity structure and generation of microbial gas..