Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy
Profitable exploitation of unconventional shale gas reservoirs relies on the success of hydraulic fracturing stimulation. This is more likely in brittle rock formations because natural and hydraulic fractures remain open after stimulation, allowing for more hydrocarbon production. Identification of...
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| Format: | Journal Article |
| Language: | English |
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PERGAMON-ELSEVIER SCIENCE LTD
2020
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| Online Access: | http://hdl.handle.net/20.500.11937/89552 |
| _version_ | 1848765243334852608 |
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| author | Mandal, Partha Pratim Rezaee, Reza Sarout, Joel |
| author_facet | Mandal, Partha Pratim Rezaee, Reza Sarout, Joel |
| author_sort | Mandal, Partha Pratim |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Profitable exploitation of unconventional shale gas reservoirs relies on the success of hydraulic fracturing stimulation. This is more likely in brittle rock formations because natural and hydraulic fractures remain open after stimulation, allowing for more hydrocarbon production. Identification of the most favourable depth intervals relies on the robust analysis of available well-logs, and on laboratory-derived mechanical and elastic data obtained under controlled stresses replicating the actual conditions at depth. Beyond their use for predictive geomechanical modelling such laboratory data can act as calibration points for existing well-logs. Well-logs can also be used to guide the selection of the rock samples to be characterised and tested in the laboratory, ensuring that they are representative of the rock formation. Here we apply the above principles and demonstrate how this improves the geomechanical appraisal of the Goldwyer formation and assesses its prospectivity. This workflow integrates Rock-eval geochemical analyses, elastic properties, anisotropy, in-situ stress state and pore pressure, mechanical brittleness and fracturing indices derived from petrophysical and sonic logs in the Theia-1 and Pictor East-1 wells. We estimated an average total organic carbon of 2 w. t.% (maximum 5 w. t.%), a moderate to high dynamic Young's modulus (14–52 GPa), a low Poisson's ratio (0.24–0.27), and an average elasticity-based brittleness index B1 of 41% in the deeper G-III unit. This unit also exhibits a low differential horizontal stress ratio and a high fracture index. Such attributes suggest a good prospectivity of the G-III unit, not only in terms of potential resources but as importantly in terms of fracability. |
| first_indexed | 2025-11-14T11:32:09Z |
| format | Journal Article |
| id | curtin-20.500.11937-89552 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T11:32:09Z |
| publishDate | 2020 |
| publisher | PERGAMON-ELSEVIER SCIENCE LTD |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-895522023-01-16T04:22:39Z Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy Mandal, Partha Pratim Rezaee, Reza Sarout, Joel Science & Technology Technology Physical Sciences Engineering, Geological Mining & Mineral Processing Engineering In-situ stress Pore pressure Brittleness Hydraulic fracturing Anisotropy Prospectivity IN-SITU STRESS MECHANICAL-PROPERTIES ELASTIC-ANISOTROPY WESTERN-AUSTRALIA PORE PRESSURE CANNING BASIN GAS-RESERVOIR ROCKS PETROPHYSICS BRITTLENESS Profitable exploitation of unconventional shale gas reservoirs relies on the success of hydraulic fracturing stimulation. This is more likely in brittle rock formations because natural and hydraulic fractures remain open after stimulation, allowing for more hydrocarbon production. Identification of the most favourable depth intervals relies on the robust analysis of available well-logs, and on laboratory-derived mechanical and elastic data obtained under controlled stresses replicating the actual conditions at depth. Beyond their use for predictive geomechanical modelling such laboratory data can act as calibration points for existing well-logs. Well-logs can also be used to guide the selection of the rock samples to be characterised and tested in the laboratory, ensuring that they are representative of the rock formation. Here we apply the above principles and demonstrate how this improves the geomechanical appraisal of the Goldwyer formation and assesses its prospectivity. This workflow integrates Rock-eval geochemical analyses, elastic properties, anisotropy, in-situ stress state and pore pressure, mechanical brittleness and fracturing indices derived from petrophysical and sonic logs in the Theia-1 and Pictor East-1 wells. We estimated an average total organic carbon of 2 w. t.% (maximum 5 w. t.%), a moderate to high dynamic Young's modulus (14–52 GPa), a low Poisson's ratio (0.24–0.27), and an average elasticity-based brittleness index B1 of 41% in the deeper G-III unit. This unit also exhibits a low differential horizontal stress ratio and a high fracture index. Such attributes suggest a good prospectivity of the G-III unit, not only in terms of potential resources but as importantly in terms of fracability. 2020 Journal Article http://hdl.handle.net/20.500.11937/89552 10.1016/j.ijrmms.2020.104513 English PERGAMON-ELSEVIER SCIENCE LTD restricted |
| spellingShingle | Science & Technology Technology Physical Sciences Engineering, Geological Mining & Mineral Processing Engineering In-situ stress Pore pressure Brittleness Hydraulic fracturing Anisotropy Prospectivity IN-SITU STRESS MECHANICAL-PROPERTIES ELASTIC-ANISOTROPY WESTERN-AUSTRALIA PORE PRESSURE CANNING BASIN GAS-RESERVOIR ROCKS PETROPHYSICS BRITTLENESS Mandal, Partha Pratim Rezaee, Reza Sarout, Joel Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy |
| title | Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy |
| title_full | Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy |
| title_fullStr | Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy |
| title_full_unstemmed | Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy |
| title_short | Geomechanical appraisal and prospectivity analysis of the Goldwyer shale accounting for stress variation and formation anisotropy |
| title_sort | geomechanical appraisal and prospectivity analysis of the goldwyer shale accounting for stress variation and formation anisotropy |
| topic | Science & Technology Technology Physical Sciences Engineering, Geological Mining & Mineral Processing Engineering In-situ stress Pore pressure Brittleness Hydraulic fracturing Anisotropy Prospectivity IN-SITU STRESS MECHANICAL-PROPERTIES ELASTIC-ANISOTROPY WESTERN-AUSTRALIA PORE PRESSURE CANNING BASIN GAS-RESERVOIR ROCKS PETROPHYSICS BRITTLENESS |
| url | http://hdl.handle.net/20.500.11937/89552 |