Evaluation On Petroleum Pool-rooling Potential Targets In The Zhaoxian Anticline Of Jinxian Sag

Jinxian Sag is located in the south of Jizhong sub-basin, crossing Jinxian, Zhaoxian and Gaoyi County in Hebei province.It is one of the important rich-oil-bearing sag. Zhaoxian Anticline is located in the central south of Jinxian Sag. The oil-bearing area has reached to 14.9km2 and the explored geologic reserve has reached to 1318.48×10⁴t from 1975.The main reservoirs are Es₂₊₃ and Es₄ + Ek₁ group. The RF to-date of geological reserve has reached to 19.3% and WCT of the reservoir is about 77.84% in this area after nearly 30 years of exploration and development. Now high WCT of the reservoir and diverse potential make more difficulty for reserve increasing in the area.Based on the analysis for the existing difficulty and comprehensive evaluation of the reservoir, the thesis sums up the structural frame-work , hydrocarbon accumulation mode and controlling factors for the reservoirs according to detailed structure interpretation integrated with the previous study result of sedimentary facies. Trap ranking has been finished through confirming the small fault block to discover the potential area for progressive development, and propose put-on production wells and profitable prospects.The structure of the area has been analyzed as a whole by stratigraphic correlation and detailed interpretation. The core structure of Zhaoxian Anticline is the area from Zhao 108 well to Zhao 22 Well, which is up-dip pitchout to the west and down-dip to the east. The main reservoirs are in the south and the core area, which are the important exploration and development areas. The reservoir type is mainly self-generation and self-storage and near oil resource reservoir. The main reservoirs are Es2+ 3 and Es₄+Ek₁ sand group. Based on the well correlation, all the oil groups in the area are correlated generally. Es₂₊₃ reservoir can be divided into three oil groups and Es₄ + Ek₁ reservoir can be divided into five groups. Es₂₊₃ reservoir is a typical structural reservoir, developed in the core area with a uniform OWC (oil-water contact). The Es₄ + Ek₁ reservoir developed in the core and south area, which is a structure-lithology reservoir with the characteristics of lithological shelter in the South wing.Finally, 3 profitable prospects and 2 evaluation block are selected as the optimized blocks for exploration through trap confirmation and reservoir study.