Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes
The relationship between P-wave velocity and fluid saturation in a porous medium is of importance for reservoir rock characterization. Forced imbibition experiments in the laboratory reveal rather complicated velocity–saturation relations, including rollover-like patterns induced by injection rate c...
| Main Authors: | , , , , |
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| Format: | Journal Article |
| Published: |
Wiley-Blackwell
2016
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| Online Access: | http://hdl.handle.net/20.500.11937/32691 |
| _version_ | 1848753733494636544 |
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| author | Liu, J. Müller, T. Qi, Q. Lebedev, Maxim Sun, W. |
| author_facet | Liu, J. Müller, T. Qi, Q. Lebedev, Maxim Sun, W. |
| author_sort | Liu, J. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The relationship between P-wave velocity and fluid saturation in a porous medium is of importance for reservoir rock characterization. Forced imbibition experiments in the laboratory reveal rather complicated velocity–saturation relations, including rollover-like patterns induced by injection rate changes. Poroelasticity theory-based patchy saturation models using a constant fluid patch size are not able to describe these velocity–saturation relations. Therefore, we incorporate a saturation-dependent patch size function into two models for patchy saturation. This recipe allows us to model observed velocity–saturation relations obtained for different and variable injection rates. The results reveal an increase in patch size with fluid saturation and show a reduction in the patch size for decreasing injection rate. This indicates that there can exist a distinct relation between patch size and injection rate. We assess the relative importance of capillarity on velocity–saturation relations and find that capillarity stiffening impairs the impact of patch size changes. Capillarity stiffening appears to be a plausible explanation when a decrease in the injection rate is expected to boost the importance of capillarity. |
| first_indexed | 2025-11-14T08:29:12Z |
| format | Journal Article |
| id | curtin-20.500.11937-32691 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:29:12Z |
| publishDate | 2016 |
| publisher | Wiley-Blackwell |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-326912017-09-13T15:27:38Z Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes Liu, J. Müller, T. Qi, Q. Lebedev, Maxim Sun, W. The relationship between P-wave velocity and fluid saturation in a porous medium is of importance for reservoir rock characterization. Forced imbibition experiments in the laboratory reveal rather complicated velocity–saturation relations, including rollover-like patterns induced by injection rate changes. Poroelasticity theory-based patchy saturation models using a constant fluid patch size are not able to describe these velocity–saturation relations. Therefore, we incorporate a saturation-dependent patch size function into two models for patchy saturation. This recipe allows us to model observed velocity–saturation relations obtained for different and variable injection rates. The results reveal an increase in patch size with fluid saturation and show a reduction in the patch size for decreasing injection rate. This indicates that there can exist a distinct relation between patch size and injection rate. We assess the relative importance of capillarity on velocity–saturation relations and find that capillarity stiffening impairs the impact of patch size changes. Capillarity stiffening appears to be a plausible explanation when a decrease in the injection rate is expected to boost the importance of capillarity. 2016 Journal Article http://hdl.handle.net/20.500.11937/32691 10.1111/1365-2478.12376 Wiley-Blackwell restricted |
| spellingShingle | Liu, J. Müller, T. Qi, Q. Lebedev, Maxim Sun, W. Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes |
| title | Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes |
| title_full | Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes |
| title_fullStr | Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes |
| title_full_unstemmed | Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes |
| title_short | Velocity-saturation relation in partially saturated rocks: Modelling the effect of injection rate changes |
| title_sort | velocity-saturation relation in partially saturated rocks: modelling the effect of injection rate changes |
| url | http://hdl.handle.net/20.500.11937/32691 |