Natural-gas-hydrate deposits: a review of in-situ properties
The Los Alamos hydrate project has concentrated on: evaluating techniques to produce gas from hydrate deposits to determine critical reservoir and production variables; predicting physical properties of hydrate-containing sediments both for their effects on production models and to allow us to devel...
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Los Alamos National Laboratory
1982
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ftunivnotexas:info:ark/67531/metadc1194981 2023-05-15T16:37:28+02:00 Natural-gas-hydrate deposits: a review of in-situ properties Halleck, P. M. Pearson, C. McGuire, P. L. Hermes, R. Mathews, M. 1982-01-01 27 pages Text https://digital.library.unt.edu/ark:/67531/metadc1194981/ English eng Los Alamos National Laboratory other: DE83000604 rep-no: LA-UR-82-2833 rep-no: CONF-820865-2 grantno: W-7405-ENG-36 osti: 6917373 https://digital.library.unt.edu/ark:/67531/metadc1194981/ ark: ark:/67531/metadc1194981 6. international ice symposium, Rolla, MO, USA, 1 Aug 1982 033000 -- Natural Gas-- Properties & Composition Well Logging 030200* -- Natural Gas-- Reserves Geology & Exploration Sediments Electric Logging Natural Gas Hydrate Deposits Resistivity Logging Geologic Deposits Physical Properties Sonic Logging Velocity 03 Natural Gas Permafrost Electric Conductivity Electrical Properties Article 1982 ftunivnotexas 2021-01-30T23:08:09Z The Los Alamos hydrate project has concentrated on: evaluating techniques to produce gas from hydrate deposits to determine critical reservoir and production variables; predicting physical properties of hydrate-containing sediments both for their effects on production models and to allow us to develop geophysical exploration and reservoir characterization techniques; and measuring properties of synthetic hydrate cores in the laboratory. Exploration techniques can help assess the size of potential hydrate deposits and determine which production techniques are appropriate for particular deposits. So little is known about the physical properties of hydrate deposits that it is difficult to develop geophysical techniques to locate or characterize them; but, because of the strong similarity between hydrates and ice, empirical relationships between ice composition and seismic velocity, electrical resistivity, density, and heat capacity that have been established for frozen rocks may be used to estimate the physical properties of hydrate deposits. Resistivities of laboratory permafrost samples are shown to follow a variation of Archie's equation. Both the resistivities and seismic velocities are functions of the unfrozen water content (Sw); however, resistivities are more sensitive to changes in Sw, varying by as much as three orders of magnitude, which may allow the use of electrical resistivity measurements to estimte the amount of hydrate in place. We estimated Sw, assuming that the dissolved salt in the pore water is concentrated as a brine phase as the hydrates form, and the brine content as a function of depth, assuming several temperature gradients and pore water salinities. Hydrate-bearing zones are characterized by high seismic velocities and electrical resistivities compared to unfrozen sediments or permafrost zones. Article in Journal/Newspaper Ice permafrost University of North Texas: UNT Digital Library |
institution |
Open Polar |
collection |
University of North Texas: UNT Digital Library |
op_collection_id |
ftunivnotexas |
language |
English |
topic |
033000 -- Natural Gas-- Properties & Composition Well Logging 030200* -- Natural Gas-- Reserves Geology & Exploration Sediments Electric Logging Natural Gas Hydrate Deposits Resistivity Logging Geologic Deposits Physical Properties Sonic Logging Velocity 03 Natural Gas Permafrost Electric Conductivity Electrical Properties |
spellingShingle |
033000 -- Natural Gas-- Properties & Composition Well Logging 030200* -- Natural Gas-- Reserves Geology & Exploration Sediments Electric Logging Natural Gas Hydrate Deposits Resistivity Logging Geologic Deposits Physical Properties Sonic Logging Velocity 03 Natural Gas Permafrost Electric Conductivity Electrical Properties Halleck, P. M. Pearson, C. McGuire, P. L. Hermes, R. Mathews, M. Natural-gas-hydrate deposits: a review of in-situ properties |
topic_facet |
033000 -- Natural Gas-- Properties & Composition Well Logging 030200* -- Natural Gas-- Reserves Geology & Exploration Sediments Electric Logging Natural Gas Hydrate Deposits Resistivity Logging Geologic Deposits Physical Properties Sonic Logging Velocity 03 Natural Gas Permafrost Electric Conductivity Electrical Properties |
description |
The Los Alamos hydrate project has concentrated on: evaluating techniques to produce gas from hydrate deposits to determine critical reservoir and production variables; predicting physical properties of hydrate-containing sediments both for their effects on production models and to allow us to develop geophysical exploration and reservoir characterization techniques; and measuring properties of synthetic hydrate cores in the laboratory. Exploration techniques can help assess the size of potential hydrate deposits and determine which production techniques are appropriate for particular deposits. So little is known about the physical properties of hydrate deposits that it is difficult to develop geophysical techniques to locate or characterize them; but, because of the strong similarity between hydrates and ice, empirical relationships between ice composition and seismic velocity, electrical resistivity, density, and heat capacity that have been established for frozen rocks may be used to estimate the physical properties of hydrate deposits. Resistivities of laboratory permafrost samples are shown to follow a variation of Archie's equation. Both the resistivities and seismic velocities are functions of the unfrozen water content (Sw); however, resistivities are more sensitive to changes in Sw, varying by as much as three orders of magnitude, which may allow the use of electrical resistivity measurements to estimte the amount of hydrate in place. We estimated Sw, assuming that the dissolved salt in the pore water is concentrated as a brine phase as the hydrates form, and the brine content as a function of depth, assuming several temperature gradients and pore water salinities. Hydrate-bearing zones are characterized by high seismic velocities and electrical resistivities compared to unfrozen sediments or permafrost zones. |
format |
Article in Journal/Newspaper |
author |
Halleck, P. M. Pearson, C. McGuire, P. L. Hermes, R. Mathews, M. |
author_facet |
Halleck, P. M. Pearson, C. McGuire, P. L. Hermes, R. Mathews, M. |
author_sort |
Halleck, P. M. |
title |
Natural-gas-hydrate deposits: a review of in-situ properties |
title_short |
Natural-gas-hydrate deposits: a review of in-situ properties |
title_full |
Natural-gas-hydrate deposits: a review of in-situ properties |
title_fullStr |
Natural-gas-hydrate deposits: a review of in-situ properties |
title_full_unstemmed |
Natural-gas-hydrate deposits: a review of in-situ properties |
title_sort |
natural-gas-hydrate deposits: a review of in-situ properties |
publisher |
Los Alamos National Laboratory |
publishDate |
1982 |
url |
https://digital.library.unt.edu/ark:/67531/metadc1194981/ |
genre |
Ice permafrost |
genre_facet |
Ice permafrost |
op_source |
6. international ice symposium, Rolla, MO, USA, 1 Aug 1982 |
op_relation |
other: DE83000604 rep-no: LA-UR-82-2833 rep-no: CONF-820865-2 grantno: W-7405-ENG-36 osti: 6917373 https://digital.library.unt.edu/ark:/67531/metadc1194981/ ark: ark:/67531/metadc1194981 |
_version_ |
1766027765003321344 |