A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements
The occurrence of gas hydrate or free gas in a porous medium changes the medium’s elastic properties. Explicit formulas for gas-hydrate or free-gas saturation of pore space on the basis of the Frenkel-Gassmann equations describe the elastic moduli and seismic velocities of a porous medium for low fr...
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Society of Exploration Geophysicists
2006
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Online Access: | https://oceanrep.geomar.de/id/eprint/6175/ https://oceanrep.geomar.de/id/eprint/6175/1/N21.full.pdf https://doi.org/10.1190/1.2192910 |
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ftoceanrep:oai:oceanrep.geomar.de:6175 2023-05-15T13:36:54+02:00 A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements Zillmer, Matthias 2006 text https://oceanrep.geomar.de/id/eprint/6175/ https://oceanrep.geomar.de/id/eprint/6175/1/N21.full.pdf https://doi.org/10.1190/1.2192910 en eng Society of Exploration Geophysicists https://oceanrep.geomar.de/id/eprint/6175/1/N21.full.pdf Zillmer, M. (2006) A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements. Open Access Geophysics, 71 (3). N21-N32. DOI 10.1190/1.2192910 <https://doi.org/10.1190/1.2192910>. doi:10.1190/1.2192910 info:eu-repo/semantics/openAccess Article PeerReviewed 2006 ftoceanrep https://doi.org/10.1190/1.2192910 2023-04-07T14:52:24Z The occurrence of gas hydrate or free gas in a porous medium changes the medium’s elastic properties. Explicit formulas for gas-hydrate or free-gas saturation of pore space on the basis of the Frenkel-Gassmann equations describe the elastic moduli and seismic velocities of a porous medium for low frequencies. A key assumption of the model is that either gas hydrate or free gas is present in the pore space in addition to water. Under this assumption, the method uses measured P- and S-wave velocities and bulk density along with estimates of the moduli and densities of the solid and fluid phases present to determine whether gas or hydrate is present. The method then determines the saturation level of either the gas or the hydrate. I apply the method to published velocity and density data from seismic studies at the antarctic Shetland margin and at the Storegga slide, offshore Norway, and to borehole log and core data from Ocean Drilling Program (ODP) Leg 164 at Blake Ridge, offshore South Carolina. A sensitivity analysis reveals that the standard deviations of the gas-hydrate and free-gas saturations reach 30%–70% of the saturations if the standard deviations of the P- and S-wave velocities and of the bulk density are 50m∕s . Article in Journal/Newspaper Antarc* Antarctic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Antarctic Norway Storegga ENVELOPE(18.251,18.251,68.645,68.645) The Antarctic GEOPHYSICS 71 3 N21 N32 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
The occurrence of gas hydrate or free gas in a porous medium changes the medium’s elastic properties. Explicit formulas for gas-hydrate or free-gas saturation of pore space on the basis of the Frenkel-Gassmann equations describe the elastic moduli and seismic velocities of a porous medium for low frequencies. A key assumption of the model is that either gas hydrate or free gas is present in the pore space in addition to water. Under this assumption, the method uses measured P- and S-wave velocities and bulk density along with estimates of the moduli and densities of the solid and fluid phases present to determine whether gas or hydrate is present. The method then determines the saturation level of either the gas or the hydrate. I apply the method to published velocity and density data from seismic studies at the antarctic Shetland margin and at the Storegga slide, offshore Norway, and to borehole log and core data from Ocean Drilling Program (ODP) Leg 164 at Blake Ridge, offshore South Carolina. A sensitivity analysis reveals that the standard deviations of the gas-hydrate and free-gas saturations reach 30%–70% of the saturations if the standard deviations of the P- and S-wave velocities and of the bulk density are 50m∕s . |
format |
Article in Journal/Newspaper |
author |
Zillmer, Matthias |
spellingShingle |
Zillmer, Matthias A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
author_facet |
Zillmer, Matthias |
author_sort |
Zillmer, Matthias |
title |
A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
title_short |
A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
title_full |
A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
title_fullStr |
A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
title_full_unstemmed |
A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
title_sort |
method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements |
publisher |
Society of Exploration Geophysicists |
publishDate |
2006 |
url |
https://oceanrep.geomar.de/id/eprint/6175/ https://oceanrep.geomar.de/id/eprint/6175/1/N21.full.pdf https://doi.org/10.1190/1.2192910 |
long_lat |
ENVELOPE(18.251,18.251,68.645,68.645) |
geographic |
Antarctic Norway Storegga The Antarctic |
geographic_facet |
Antarctic Norway Storegga The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
https://oceanrep.geomar.de/id/eprint/6175/1/N21.full.pdf Zillmer, M. (2006) A method for determining gas-hydrate or free-gas saturation of porous media from seismic measurements. Open Access Geophysics, 71 (3). N21-N32. DOI 10.1190/1.2192910 <https://doi.org/10.1190/1.2192910>. doi:10.1190/1.2192910 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1190/1.2192910 |
container_title |
GEOPHYSICS |
container_volume |
71 |
container_issue |
3 |
container_start_page |
N21 |
op_container_end_page |
N32 |
_version_ |
1766085464445419520 |