Comprehensive Evaluation Of Shahejie Formation Hydrocarbon Target In The Weicheng Area Of Dongpu Depression

Weicheng oil field is situated at the north of central uplift belt of Dongpu depression, adjacent to the Pu-Wei petroleum-generation sub-depression, in which abundant oil and gas resource occurs. It is also the favorable oil & gas accumulation area of Dongpu depression owing to a series of fault traps formed by rift structure. Weicheng oil field developed two fault systems (Weidong and Weixi fault systems), and in which many and dense little faults developed. It belongs to the typical complex fault-block reservoir. In Weicheng horst structure, because of deep buried and high dip angle, and influenced by strata and structure, oil and gas exploration is faced with great difficulty. In view of the geological feature of developed little faults and complex structure and poor seismic data in Weicheng area, based on 3-D seismic data, focused on the research of structure, comprehensive application of logging, drilling, high resolution dip data and production data, through the technology of 3-D structural interpretation and muti-method recognizing fault, tectonic form development of little fault and combination regualrity of flat and section and sealing pattern of fault are deeply analyzed and studied. And the identification level of little fault, little fault-block and little oil reservoir is improved. Through the study of rock-electricity and the relation of reservoir physical property, oiliness and log response, all kinds of charts have been drawn, the log interpretation criterion from Es1-Es4 in Weicheng oil field has been rebuilt, and the generation mechanism and interpretation criterion of low-resistance oil reservoir has been analyzed as well. Finally, based on the comprehensive study of strata, structure, reservoir, type of oil & gas pool and hydrocarbon accumulation, sixteen prospect targets from divided four sub-tectonic zones have been evaluated, and optimized favorable targets have been drilled and good results received, which makes tremendous contribution for the oil & gas exploration and development in Weicheng oil field.