Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia
Geopressure prediction is crucial because all drilling programs require estimation of abnormal pressured zones. The use of rock fabric deformational relics at variable depths to determine heterogeneity in overpressure zones in reservoir has not been explored. Therefore, the aim of this paper is to u...
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| Format: | Article |
| Language: | English |
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KeAi Communications Co., Ltd.
2020-02-01
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| Series: | Journal of Natural Gas Geoscience |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2468256X19300811 |
| _version_ | 1797766598976602112 |
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| author | I. Yusuf E. Padmanabhan J.A. Gamez Vintaned C. Weng Sum |
| author_facet | I. Yusuf E. Padmanabhan J.A. Gamez Vintaned C. Weng Sum |
| author_sort | I. Yusuf |
| collection | DOAJ |
| description | Geopressure prediction is crucial because all drilling programs require estimation of abnormal pressured zones. The use of rock fabric deformational relics at variable depths to determine heterogeneity in overpressure zones in reservoir has not been explored. Therefore, the aim of this paper is to use petrography to determine intrinsic variations within overpressure zones. Understanding petrographic expression of overpressure on reservoir lithofacies at variable depths will enhance the prediction of overpressure in reservoirs that are not initially logged by subsurface pressure detecting tools. Thin section and scanning electron microscopy (SEM) petrography was used to study rock fabric. The petrophysical properties of the rock samples were measured using mercury porosimetry. Two lithofacies were discretized in a single reservoir i.e., massive friable fine-grained sandstone (MFFS) (Layer 1) and massive fine-grained sandstone (MFS) (Layer 2). The underlying layer (Layer 2) is dominated by sutured quartz grains, lenticular grain orientation, quartz overgrowth and relatively low porosity and permeability. The quartz grains are polycrystalline and characterized by planar and conchoidal fractures, in contrast to the overlying MFFS layer dominated by monocrystalline and platy quartz grains. The petrographic studies show overpressure variation can be characterized intrinsically by quartz deformational features and overall texture differences. Keywords: Overpressure zones, Quartz morphology, Petrographic expression, Baram Delta |
| first_indexed | 2024-03-12T20:27:34Z |
| format | Article |
| id | doaj.art-b1bfbb06aed6496c99aef56a5bcecd41 |
| institution | Directory Open Access Journal |
| issn | 2468-256X |
| language | English |
| last_indexed | 2024-03-12T20:27:34Z |
| publishDate | 2020-02-01 |
| publisher | KeAi Communications Co., Ltd. |
| record_format | Article |
| series | Journal of Natural Gas Geoscience |
| spelling | doaj.art-b1bfbb06aed6496c99aef56a5bcecd412023-08-02T00:25:22ZengKeAi Communications Co., Ltd.Journal of Natural Gas Geoscience2468-256X2020-02-01512127Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, MalaysiaI. Yusuf0E. Padmanabhan1J.A. Gamez Vintaned2C. Weng Sum3Department of Geosciences, Faculty of Geosciences and Petroleum Engineering, Universiti Teknologi PETRONAS, 32610, Seri Iskandar, Perak, Malaysia; Department of Geology and Mining, Faculty of Applied Science and Technology, Ibrahim Badamasi Babangida University, Lapai, Niger state, Nigeria; Corresponding author. Department of Geology and Mining, Faculty of Applied science and Technology, Ibrahim Badamasi Babangida University, Lapai, Niger state. Nigeria.Department of Geosciences, Faculty of Geosciences and Petroleum Engineering, Universiti Teknologi PETRONAS, 32610, Seri Iskandar, Perak, MalaysiaDepartment of Geosciences, Faculty of Geosciences and Petroleum Engineering, Universiti Teknologi PETRONAS, 32610, Seri Iskandar, Perak, MalaysiaDepartment of Geosciences, Faculty of Geosciences and Petroleum Engineering, Universiti Teknologi PETRONAS, 32610, Seri Iskandar, Perak, MalaysiaGeopressure prediction is crucial because all drilling programs require estimation of abnormal pressured zones. The use of rock fabric deformational relics at variable depths to determine heterogeneity in overpressure zones in reservoir has not been explored. Therefore, the aim of this paper is to use petrography to determine intrinsic variations within overpressure zones. Understanding petrographic expression of overpressure on reservoir lithofacies at variable depths will enhance the prediction of overpressure in reservoirs that are not initially logged by subsurface pressure detecting tools. Thin section and scanning electron microscopy (SEM) petrography was used to study rock fabric. The petrophysical properties of the rock samples were measured using mercury porosimetry. Two lithofacies were discretized in a single reservoir i.e., massive friable fine-grained sandstone (MFFS) (Layer 1) and massive fine-grained sandstone (MFS) (Layer 2). The underlying layer (Layer 2) is dominated by sutured quartz grains, lenticular grain orientation, quartz overgrowth and relatively low porosity and permeability. The quartz grains are polycrystalline and characterized by planar and conchoidal fractures, in contrast to the overlying MFFS layer dominated by monocrystalline and platy quartz grains. The petrographic studies show overpressure variation can be characterized intrinsically by quartz deformational features and overall texture differences. Keywords: Overpressure zones, Quartz morphology, Petrographic expression, Baram Deltahttp://www.sciencedirect.com/science/article/pii/S2468256X19300811 |
| spellingShingle | I. Yusuf E. Padmanabhan J.A. Gamez Vintaned C. Weng Sum Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia Journal of Natural Gas Geoscience |
| title | Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia |
| title_full | Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia |
| title_fullStr | Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia |
| title_full_unstemmed | Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia |
| title_short | Heterogeneity in the overpressure zones in West Baram Delta, offshore-Sarawak, Malaysia |
| title_sort | heterogeneity in the overpressure zones in west baram delta offshore sarawak malaysia |
| url | http://www.sciencedirect.com/science/article/pii/S2468256X19300811 |
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