James A Smith
James A Smith is a Geophysicist with the Earthquake Hazards Program.
Science and Products
Filter Total Items: 88
A geochemical reconnaissance of the Alid volcanic center and geothermal system, Danakil depression, Eritrea A geochemical reconnaissance of the Alid volcanic center and geothermal system, Danakil depression, Eritrea
Geological and geochemical studies indicate that a high-temperature geothermal system underlies the Alid volcanic center in the northern Danakil depression of Eritrea. Alid is a very late-Pleistocene structural dome formed by shallow intrusion of rhyolitic magma, some of which vented as lavas and pyroclastic flows. Fumaroles and boiling pools distributed widely over an area of ~10 km2 on...
Authors
J. Lowenstern, C. Janik, R.O. Fournier, T. Tesfai, W. Duffield, M.A. Clynne, James G. Smith, L. Woldegiorgis, K. Weldemariam, G. Kahsai
3-Dimensional visualization of the Medicine Lake Highland, CA: Topography, geology, geophysics, and hydrology 3-Dimensional visualization of the Medicine Lake Highland, CA: Topography, geology, geophysics, and hydrology
No abstract available.
Authors
J. Lowenstern, Michele Killgore, Robert Mariner, R.J. Blakely, James G. Smith, J.M. Donnelly-Nolan
Geothermal potential of the Alid Volcanic Center, Danakil Depression, Eritrea Geothermal potential of the Alid Volcanic Center, Danakil Depression, Eritrea
No abstract available.
Authors
W. Duffield, T.D. Bullen, M.A. Clynne, R.O. Fournier, C. Janik, M. Lanphere, Jacob Lowenstern, James G. Smith, L.W. Giorgis, Gabreab Kahsai, K.W. Mariam, Theoderos Tesfai
Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution
Isostatic residual gravity anomalies in the southern Cascade Range of northern California and southern Oregon are spatially correlated with broad zones of Quaternary magmatism as reflected by the total volume of Quaternary volcanic products, the distribution of Quaternary vents, and the anomalously low teleseismic P wave velocities in the upper 30 km of crust. The orientation of...
Authors
R.J. Blakely, R.L. Christiansen, M. Guffanti, R.E. Wells, J.M. Donnelly-Nolan, L.J. Muffler, M.A. Clynne, James G. Smith
Quantification of natural vapor fluxes of trichloroethene in the unsaturated zone at Picatinny Arsenal, New Jersey Quantification of natural vapor fluxes of trichloroethene in the unsaturated zone at Picatinny Arsenal, New Jersey
The upward flux of trichloroethene (TCE) vapor through the unsaturated zone above a contaminated, water-table aquifer at Picatinny Arsenal, New Jersey, has been studied under natural conditions over a 12-month period. Vertical gas-phase diffusion fluxes were estimated indirectly by measuring the TCE vapor concentration gradient in the unsaturated zone and using Fick's law to calculate...
Authors
James A. Smith, Amy Tisdale, H. Cho
Geology and geothermal potential of Alid volcanic center, Eritrea, Africa Geology and geothermal potential of Alid volcanic center, Eritrea, Africa
Alid volcanic center, a 700-meter-tall mountain in Eritrea, northeast Africa, straddles the axis of an active crustal-spreading center called the Danakil Depression. Boiling-temperature fumaroles are common on Alid, and their gas compositions indicate a reservoir temperature of at least 250 ??C. The history of volcanism and the high reservoir temperature indicated by the Alid fumarole...
Authors
Michael Clynne, Wendell Duffield, Robert Fournier, Leake Giorgis, Cathy Janik, Gabreab Kahsai, Jacob Lowenstern, Kidane Mariam, James G. Smith, Theoderos Tesfai
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 88
A geochemical reconnaissance of the Alid volcanic center and geothermal system, Danakil depression, Eritrea A geochemical reconnaissance of the Alid volcanic center and geothermal system, Danakil depression, Eritrea
Geological and geochemical studies indicate that a high-temperature geothermal system underlies the Alid volcanic center in the northern Danakil depression of Eritrea. Alid is a very late-Pleistocene structural dome formed by shallow intrusion of rhyolitic magma, some of which vented as lavas and pyroclastic flows. Fumaroles and boiling pools distributed widely over an area of ~10 km2 on...
Authors
J. Lowenstern, C. Janik, R.O. Fournier, T. Tesfai, W. Duffield, M.A. Clynne, James G. Smith, L. Woldegiorgis, K. Weldemariam, G. Kahsai
3-Dimensional visualization of the Medicine Lake Highland, CA: Topography, geology, geophysics, and hydrology 3-Dimensional visualization of the Medicine Lake Highland, CA: Topography, geology, geophysics, and hydrology
No abstract available.
Authors
J. Lowenstern, Michele Killgore, Robert Mariner, R.J. Blakely, James G. Smith, J.M. Donnelly-Nolan
Geothermal potential of the Alid Volcanic Center, Danakil Depression, Eritrea Geothermal potential of the Alid Volcanic Center, Danakil Depression, Eritrea
No abstract available.
Authors
W. Duffield, T.D. Bullen, M.A. Clynne, R.O. Fournier, C. Janik, M. Lanphere, Jacob Lowenstern, James G. Smith, L.W. Giorgis, Gabreab Kahsai, K.W. Mariam, Theoderos Tesfai
Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution Gravity anomalies, Quaternary vents, and Quaternary faults in the southern Cascade Range, Oregon and California: Implications for arc and backarc evolution
Isostatic residual gravity anomalies in the southern Cascade Range of northern California and southern Oregon are spatially correlated with broad zones of Quaternary magmatism as reflected by the total volume of Quaternary volcanic products, the distribution of Quaternary vents, and the anomalously low teleseismic P wave velocities in the upper 30 km of crust. The orientation of...
Authors
R.J. Blakely, R.L. Christiansen, M. Guffanti, R.E. Wells, J.M. Donnelly-Nolan, L.J. Muffler, M.A. Clynne, James G. Smith
Quantification of natural vapor fluxes of trichloroethene in the unsaturated zone at Picatinny Arsenal, New Jersey Quantification of natural vapor fluxes of trichloroethene in the unsaturated zone at Picatinny Arsenal, New Jersey
The upward flux of trichloroethene (TCE) vapor through the unsaturated zone above a contaminated, water-table aquifer at Picatinny Arsenal, New Jersey, has been studied under natural conditions over a 12-month period. Vertical gas-phase diffusion fluxes were estimated indirectly by measuring the TCE vapor concentration gradient in the unsaturated zone and using Fick's law to calculate...
Authors
James A. Smith, Amy Tisdale, H. Cho
Geology and geothermal potential of Alid volcanic center, Eritrea, Africa Geology and geothermal potential of Alid volcanic center, Eritrea, Africa
Alid volcanic center, a 700-meter-tall mountain in Eritrea, northeast Africa, straddles the axis of an active crustal-spreading center called the Danakil Depression. Boiling-temperature fumaroles are common on Alid, and their gas compositions indicate a reservoir temperature of at least 250 ??C. The history of volcanism and the high reservoir temperature indicated by the Alid fumarole...
Authors
Michael Clynne, Wendell Duffield, Robert Fournier, Leake Giorgis, Cathy Janik, Gabreab Kahsai, Jacob Lowenstern, Kidane Mariam, James G. Smith, Theoderos Tesfai
Non-USGS Publications**
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.