Quantitative Characterization and Distribution Prediction of Structural Fracture in Ultra-deep Tight Sandstone Reservoir—A Case Study of Keshen5 Gas Pool in Kuqa Depression of Tarim Basin(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2017年第05期
- Page:
- 652-668
- Research Field:
- 基础地质与矿产地质
- Publishing date:
Info
- Title:
- Quantitative Characterization and Distribution Prediction of Structural Fracture in Ultra-deep Tight Sandstone Reservoir—A Case Study of Keshen5 Gas Pool in Kuqa Depression of Tarim Basin
- Author(s):
- WANG Ke; ZHANG Hui-liang; ZHANG Rong-hu; WANG Jun-peng; SUN Xiong-wei; YANG Xue-jun
- 1. PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, China; 2. PetroChina Tarim Oilfield Company, Korla 841000, Xinjiang, China; 3. PetroChina Hangzhou Research Institute of Geology, Hangzhou 310023, Zhejiang, China
- Keywords:
- tight sandstone; structural fracture; tectonic stress field; quantitative characterization; distribution prediction; ultra-deep; Kuqa depression; Tarim Basin
- PACS:
- P618.130.2;TE122.2
- DOI:
- -
- Abstract:
- Combined with core and thin section observation, CT scan, image logging interpretation, the characteristics of structural fracture of Keshen5 gas pool in Kuqa depression of Tarim Basin were quantitatively characterized; the origin and validity of structural fracture were analyzed; and the spatial distribution regularity of structural fracture was predicted by numerical simulation of tectonic stress field. The results show that the structural fractures of Keshen5 gas pool are mostly high dip angle or upright ones and highly filled by calcite, in which the apertures distribute at 0-0.4 mm; microscopic fractures, in which the apertures mostly distribute at 20-30μm, include grain-crossed fracture and mineral grain crack; in vertical, intensively developed sections and undeveloped sections of structural facture have the regularity of interphase distribution; there are three periods of structural fractures formed in Cretaceous, Paleogene and Neogene-Quarternary, respectively, in which the 3rd period of structural fracture is one of the key factors for industrial gas pool finally formed in Keshen5 area; palaeo-tectonic stress field determines the system characteristics and quantity of structural fractures, and the levorotatory shearing stress along boundary faults results in that the direction of tectonic stress and structural fractures changes from ~EW at southwest to ~SN at northwest of the anticline; present tectonic stress field generally would not form new fractures, but affects the effectiveness of pre-exist fractures; the high position of anticline has low linear density of structural fracture, but high aperture, porosity and permeability, therefore, the average gas production capacity of single well is also high correspondingly; in vertical, with the deepening of depth, the linear density of structural fracture increases while the effective aperture decreases, which means that the integrated development extent reduces; the controlling effect of unconformity on structural fracture validity is restricted within about 70 m.
Last Update: 2017-10-19