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Fracture Development in Phanok Khao Reservoirs from Outcrop Integrated with FMI, Korat Basin, North-East Thailand |
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| รหัสดีโอไอ | |
| Creator | Jakkree Kongchum |
| Title | Fracture Development in Phanok Khao Reservoirs from Outcrop Integrated with FMI, Korat Basin, North-East Thailand |
| Contributor | - |
| Publisher | Department of Geology, Chulalongkorn University |
| Publication Year | 2561 |
| Journal Title | Bulletin of Earth Sciences of Thailand (BEST) |
| Journal Vol. | 10 |
| Journal No. | 2 |
| Page no. | 72-82 |
| Keyword | Fracture evolution, Diagenesis process, Uplift, Pha Nok Kao Formation |
| URL Website | https://www.bestjournal.org/ |
| Website title | Bulletin of Earth Sciences of Thailand |
| ISSN | 1906-280X |
| Abstract | Production from fractured carbonate reservoirs in North-East Thailand has been ongoing in the Phu Horm field and focused in the "Pha Nok Kao Formation". There, the relative timing of fracture events, the relationship to fluid-cement histories, and ties to the Indosinian or Himalayan Orogenies are not well understood. Therefore, in an attempt to look more regionally at defining effects from both tectonic events, this study focused on three outcrops across North-East to Western Thailand, where previous mapping has shown structures related to both orogenic events are present. The selected areas are; Chum Phae quarry, Banphot Phisai quarry and U-Thong quarry. The most significant area is the Chum Phae quarry, which contains lithologies, structures and diagenetic features that can be directly related to the Pha Nok Kao reservoirs in Sinphuhorm field. Fracture orientation analysis was integrated with petrographic study to better define relative timing and model the structural geometry with the integration of fracture development across the three areas. Stable isotope crossplots of carbon and oxygen (C-O), using orientation-aware isotope samples, defined variable fluid events, which can classify the diagenetic evolution in each fracture. The isotopic plotfields define 2 trends of reactivated fractures that experienced crossflows of deep mixing meteoric waters during later tectonic uplift. Moreover, North-East Thailand in the vicinity of Sinphuhorm field did not experience significant cross-flows of Indosinian deformation fluids, nor the Mesozoic hydrothermal fluids that have overprinted once-fractured metamorphic carbonates in Central and Western Thailand. The highest potential for open fracture trends is found in fractured carbonates preserving isotopic evidence of being subject to reactivation during the youngest tectonic event (Himalayan Orogeny). |