Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters
Abstract Seismic bottom simulating reflections (BSR) analysis and seismic inversion are commonly used for gas hydrate reservoir interpretation. The relationship between gas hydrate saturation and elastic parameters can be influenced by gas hydrate occurrence state (e.g. pore-filling type gas hydrate...
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Online Access: | http://dx.doi.org/10.1093/jge/gxac100 https://academic.oup.com/jge/article-pdf/20/1/117/48758593/gxac100.pdf |
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croxfordunivpr:10.1093/jge/gxac100 2023-05-15T17:58:22+02:00 Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters Wu, Cunzhi Han, Lei Zhang, Feng Liu, Junzhou Chen, Haifeng Di, Bangrang National Natural Science Foundation of China Foundation of Sinopec Key Laboratory of Seismic Elastic Wave Technology CNPC 2023 http://dx.doi.org/10.1093/jge/gxac100 https://academic.oup.com/jge/article-pdf/20/1/117/48758593/gxac100.pdf en eng Oxford University Press (OUP) https://creativecommons.org/licenses/by/4.0/ CC-BY Journal of Geophysics and Engineering volume 20, issue 1, page 117-127 ISSN 1742-2132 1742-2140 Management, Monitoring, Policy and Law Industrial and Manufacturing Engineering Geology Geophysics journal-article 2023 croxfordunivpr https://doi.org/10.1093/jge/gxac100 2023-01-20T11:05:20Z Abstract Seismic bottom simulating reflections (BSR) analysis and seismic inversion are commonly used for gas hydrate reservoir interpretation. The relationship between gas hydrate saturation and elastic parameters can be influenced by gas hydrate occurrence state (e.g. pore-filling type gas hydrate or load-bearing type gas hydrate), and this may cause inaccurate interpretation. We first used the simplified three-phase Biot equation (STPBE) to model a formation containing two types of gas hydrate at the same time. Then the effects of occurrence state and authigenic minerals on the relationship between saturation and varied elastic parameters are analysed. Results show that bulk modulus (K), shear modulus ($\mu $), P-wave velocity (${V}_p$), S-wave velocity (${V}_s$), velocity ratio (${V}_p/{V}_s$), Poisson's ratio (v) and $\mu \rho $ increase at different rates with gas hydrate saturation, ${V}_p/{V}_s$ and v show relative higher sensitivity to occurrence state. Ratios of elastic parameter increments are further used to highlight the anomalies caused by gas hydrate. Four attributes ($\Delta K/\Delta \mu $, $\Delta {V}_p/\Delta {V}_s$, $\Delta ({V}_p/{V}_s)/\Delta u $ and $\Delta \lambda \rho /\Delta \mu \rho $) show good sensitivity to both gas hydrate saturation and occurrence state. $\Delta ({V}_p/{V}_s)/\Delta u $ and $\Delta \lambda \rho /\Delta \mu \rho $ can be used to distinguish gas hydrate with varied occurrence states from authigenic minerals (limestone, opal, pyrite and others). Two selected sensitive attributes $\Delta ({V}_p/{V}_s)/\Delta u $ and $\Delta \lambda \rho /\Delta \mu \rho $ are applied to well logs, four gas hydrate-bearing intervals in well 2L-38 from Mallik permafrost area in Canada and one gas hydrate-bearing interval in well A from Shenhu area in South China Sea are identified. These results are consistent with the interpreted result from the resistivity log using Archie's formula. This investigation may provide effective tools for the seismic interpretation of gas hydrate reservoirs. Article in Journal/Newspaper permafrost Oxford University Press (via Crossref) Canada Lambda ENVELOPE(-62.983,-62.983,-64.300,-64.300) Rho ENVELOPE(-63.000,-63.000,-64.300,-64.300) Journal of Geophysics and Engineering 20 1 117 127 |
institution |
Open Polar |
collection |
Oxford University Press (via Crossref) |
op_collection_id |
croxfordunivpr |
language |
English |
topic |
Management, Monitoring, Policy and Law Industrial and Manufacturing Engineering Geology Geophysics |
spellingShingle |
Management, Monitoring, Policy and Law Industrial and Manufacturing Engineering Geology Geophysics Wu, Cunzhi Han, Lei Zhang, Feng Liu, Junzhou Chen, Haifeng Di, Bangrang Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
topic_facet |
Management, Monitoring, Policy and Law Industrial and Manufacturing Engineering Geology Geophysics |
description |
Abstract Seismic bottom simulating reflections (BSR) analysis and seismic inversion are commonly used for gas hydrate reservoir interpretation. The relationship between gas hydrate saturation and elastic parameters can be influenced by gas hydrate occurrence state (e.g. pore-filling type gas hydrate or load-bearing type gas hydrate), and this may cause inaccurate interpretation. We first used the simplified three-phase Biot equation (STPBE) to model a formation containing two types of gas hydrate at the same time. Then the effects of occurrence state and authigenic minerals on the relationship between saturation and varied elastic parameters are analysed. Results show that bulk modulus (K), shear modulus ($\mu $), P-wave velocity (${V}_p$), S-wave velocity (${V}_s$), velocity ratio (${V}_p/{V}_s$), Poisson's ratio (v) and $\mu \rho $ increase at different rates with gas hydrate saturation, ${V}_p/{V}_s$ and v show relative higher sensitivity to occurrence state. Ratios of elastic parameter increments are further used to highlight the anomalies caused by gas hydrate. Four attributes ($\Delta K/\Delta \mu $, $\Delta {V}_p/\Delta {V}_s$, $\Delta ({V}_p/{V}_s)/\Delta u $ and $\Delta \lambda \rho /\Delta \mu \rho $) show good sensitivity to both gas hydrate saturation and occurrence state. $\Delta ({V}_p/{V}_s)/\Delta u $ and $\Delta \lambda \rho /\Delta \mu \rho $ can be used to distinguish gas hydrate with varied occurrence states from authigenic minerals (limestone, opal, pyrite and others). Two selected sensitive attributes $\Delta ({V}_p/{V}_s)/\Delta u $ and $\Delta \lambda \rho /\Delta \mu \rho $ are applied to well logs, four gas hydrate-bearing intervals in well 2L-38 from Mallik permafrost area in Canada and one gas hydrate-bearing interval in well A from Shenhu area in South China Sea are identified. These results are consistent with the interpreted result from the resistivity log using Archie's formula. This investigation may provide effective tools for the seismic interpretation of gas hydrate reservoirs. |
author2 |
National Natural Science Foundation of China Foundation of Sinopec Key Laboratory of Seismic Elastic Wave Technology CNPC |
format |
Article in Journal/Newspaper |
author |
Wu, Cunzhi Han, Lei Zhang, Feng Liu, Junzhou Chen, Haifeng Di, Bangrang |
author_facet |
Wu, Cunzhi Han, Lei Zhang, Feng Liu, Junzhou Chen, Haifeng Di, Bangrang |
author_sort |
Wu, Cunzhi |
title |
Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
title_short |
Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
title_full |
Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
title_fullStr |
Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
title_full_unstemmed |
Gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
title_sort |
gas hydrate reservoir identification based on rock physics modelling and sensitive elastic parameters |
publisher |
Oxford University Press (OUP) |
publishDate |
2023 |
url |
http://dx.doi.org/10.1093/jge/gxac100 https://academic.oup.com/jge/article-pdf/20/1/117/48758593/gxac100.pdf |
long_lat |
ENVELOPE(-62.983,-62.983,-64.300,-64.300) ENVELOPE(-63.000,-63.000,-64.300,-64.300) |
geographic |
Canada Lambda Rho |
geographic_facet |
Canada Lambda Rho |
genre |
permafrost |
genre_facet |
permafrost |
op_source |
Journal of Geophysics and Engineering volume 20, issue 1, page 117-127 ISSN 1742-2132 1742-2140 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1093/jge/gxac100 |
container_title |
Journal of Geophysics and Engineering |
container_volume |
20 |
container_issue |
1 |
container_start_page |
117 |
op_container_end_page |
127 |
_version_ |
1766166957087784960 |