John Pohlman, PhD
John Pohlman is a Research Chemist with the Woods Hole Coastal and Marine Science Center Gas Hydrates Project.
Science and Products
Filter Total Items: 62
Investigating gas hydrate as a factor in accretionary margin frontal ridge slope failures and cold seep biogeochemistry Investigating gas hydrate as a factor in accretionary margin frontal ridge slope failures and cold seep biogeochemistry
During August 2008, a research expedition (2008-007-PGC) was carried out offshore Vancouver Island on the northern Cascadia Margin (Figure 1) to study the role of gas hydrate in slope stability and cold seep biogeochemistry. The cruise was organized by the Geological Survey of Canada (GSC) as part of the Earth Science Sector, Natural Gas Hydrate Program, Natural Resources Canada (NRCan)...
Authors
R. Enkin, L. Esteban, R. Haacke, T.S. Hamilton, M. Hogg, L. Lapham, G. Middleton, P. Neelands, John W. Pohlman, M Riedel, K. Rose, A. Schlesinger, G. Standen, A. Stephenson, S. Taylor, W. Waite, X. Wang
Climate change and global carbon cycle: Perspectives and opportunities Climate change and global carbon cycle: Perspectives and opportunities
The relevance of methane hydrates research to broader societal themes is often framed in terms of methane’s role in the global carbon cycle and its potential contribution to future climate change. To date, investigations of these fundamental issues have remained largely disconnected from applied studies focused on locating natural gas hydrate deposits, developing production technologies...
Authors
Carolyn D. Ruppel, John W. Pohlman
Application of RHIZON samplers to obtain high-resolution pore-fluid records during geochemical investigations of gas hydrate systems Application of RHIZON samplers to obtain high-resolution pore-fluid records during geochemical investigations of gas hydrate systems
Obtaining accurate, high-resolution profiles of pore fluid constituents is critical for characterizing the subsurface geochemistry of hydrate-bearing sediments. Tightly-constrained downcore profiles provide clues about fluid sources, fluid flow, and the milieu of chemical and diagenetic reactions, all of which are used to interpret where and why gas and gas hydrate occur in the natural...
Authors
John W. Pohlman, M Riedel, William F. Waite, K. Rose, L. Lapham
Assessing sulfate reduction and methane cycling in a high salinity pore water system in the northern Gulf of Mexico Assessing sulfate reduction and methane cycling in a high salinity pore water system in the northern Gulf of Mexico
Pore waters extracted from 18 piston cores obtained on and near a salt-cored bathymetric high in Keathley Canyon lease block 151 in the northern Gulf of Mexico contain elevated concentrations of chloride (up to 838 mM) and have pore water chemical concentration profiles that exhibit extensive departures (concavity) from steady-state (linear) diffusive equilibrium with depth. Minimum...
Authors
J. W. Pohlman, C. Ruppel, D. R. Hutchinson, R. Downer, R.B. Coffin
Rapid sea level rise and ice sheet response to 8,200-year climate event Rapid sea level rise and ice sheet response to 8,200-year climate event
The largest abrupt climatic reversal of the Holocene interglacial, the cooling event 8.6–8.2 thousand years ago (ka), was probably caused by catastrophic release of glacial Lake Agassiz-Ojibway, which slowed Atlantic meridional overturning circulation (AMOC) and cooled global climate. Geophysical surveys and sediment cores from Chesapeake Bay reveal the pattern of sea level rise during...
Authors
T. M. Cronin, P.R. Vogt, Debra A. Willard, R. Thunell, J. Halka, M. Berke, J. Pohlman
Gas hydrate transect across northern Cascadia margin Gas hydrate transect across northern Cascadia margin
Gas hydrate is a solid compound mainly comprised of methane and water that is stable under low temperature and high pressure conditions. Usually found in offshore environments with water depths exceeding about 500 meters and in arctic regions associated with permafrost, gas hydrates form an efficient storage system for natural gas. Hence, they may represent an important future energy...
Authors
M. Riedel, T. Collett, M. Malone, F. Akiba, M. Blanc-Valleron, M. Ellis, G. Guerin, Y. Hashimoto, V. Heuer, Y. Higashi, M. Holland, P. Jackson, M. Kaneko, M. Kastner, J.-H. Kim, H. Kitajima, P. Long, A. Malinverno, Gwen E. Myers, L. Palekar, J. Pohlman, P. Schultheiss, B. Teichert, M. Torres, A. Trehu, Jingyuan Wang, U. Worthmann, H. Yoshioka
Science and Products
Filter Total Items: 62
Investigating gas hydrate as a factor in accretionary margin frontal ridge slope failures and cold seep biogeochemistry Investigating gas hydrate as a factor in accretionary margin frontal ridge slope failures and cold seep biogeochemistry
During August 2008, a research expedition (2008-007-PGC) was carried out offshore Vancouver Island on the northern Cascadia Margin (Figure 1) to study the role of gas hydrate in slope stability and cold seep biogeochemistry. The cruise was organized by the Geological Survey of Canada (GSC) as part of the Earth Science Sector, Natural Gas Hydrate Program, Natural Resources Canada (NRCan)...
Authors
R. Enkin, L. Esteban, R. Haacke, T.S. Hamilton, M. Hogg, L. Lapham, G. Middleton, P. Neelands, John W. Pohlman, M Riedel, K. Rose, A. Schlesinger, G. Standen, A. Stephenson, S. Taylor, W. Waite, X. Wang
Climate change and global carbon cycle: Perspectives and opportunities Climate change and global carbon cycle: Perspectives and opportunities
The relevance of methane hydrates research to broader societal themes is often framed in terms of methane’s role in the global carbon cycle and its potential contribution to future climate change. To date, investigations of these fundamental issues have remained largely disconnected from applied studies focused on locating natural gas hydrate deposits, developing production technologies...
Authors
Carolyn D. Ruppel, John W. Pohlman
Application of RHIZON samplers to obtain high-resolution pore-fluid records during geochemical investigations of gas hydrate systems Application of RHIZON samplers to obtain high-resolution pore-fluid records during geochemical investigations of gas hydrate systems
Obtaining accurate, high-resolution profiles of pore fluid constituents is critical for characterizing the subsurface geochemistry of hydrate-bearing sediments. Tightly-constrained downcore profiles provide clues about fluid sources, fluid flow, and the milieu of chemical and diagenetic reactions, all of which are used to interpret where and why gas and gas hydrate occur in the natural...
Authors
John W. Pohlman, M Riedel, William F. Waite, K. Rose, L. Lapham
Assessing sulfate reduction and methane cycling in a high salinity pore water system in the northern Gulf of Mexico Assessing sulfate reduction and methane cycling in a high salinity pore water system in the northern Gulf of Mexico
Pore waters extracted from 18 piston cores obtained on and near a salt-cored bathymetric high in Keathley Canyon lease block 151 in the northern Gulf of Mexico contain elevated concentrations of chloride (up to 838 mM) and have pore water chemical concentration profiles that exhibit extensive departures (concavity) from steady-state (linear) diffusive equilibrium with depth. Minimum...
Authors
J. W. Pohlman, C. Ruppel, D. R. Hutchinson, R. Downer, R.B. Coffin
Rapid sea level rise and ice sheet response to 8,200-year climate event Rapid sea level rise and ice sheet response to 8,200-year climate event
The largest abrupt climatic reversal of the Holocene interglacial, the cooling event 8.6–8.2 thousand years ago (ka), was probably caused by catastrophic release of glacial Lake Agassiz-Ojibway, which slowed Atlantic meridional overturning circulation (AMOC) and cooled global climate. Geophysical surveys and sediment cores from Chesapeake Bay reveal the pattern of sea level rise during...
Authors
T. M. Cronin, P.R. Vogt, Debra A. Willard, R. Thunell, J. Halka, M. Berke, J. Pohlman
Gas hydrate transect across northern Cascadia margin Gas hydrate transect across northern Cascadia margin
Gas hydrate is a solid compound mainly comprised of methane and water that is stable under low temperature and high pressure conditions. Usually found in offshore environments with water depths exceeding about 500 meters and in arctic regions associated with permafrost, gas hydrates form an efficient storage system for natural gas. Hence, they may represent an important future energy...
Authors
M. Riedel, T. Collett, M. Malone, F. Akiba, M. Blanc-Valleron, M. Ellis, G. Guerin, Y. Hashimoto, V. Heuer, Y. Higashi, M. Holland, P. Jackson, M. Kaneko, M. Kastner, J.-H. Kim, H. Kitajima, P. Long, A. Malinverno, Gwen E. Myers, L. Palekar, J. Pohlman, P. Schultheiss, B. Teichert, M. Torres, A. Trehu, Jingyuan Wang, U. Worthmann, H. Yoshioka