The Fine Characterization Of Micro-structure Of Complex Fault Block Reservoir In Gaoshangpu Oil Field

Remaining oil is closely related to micro-structure. Micro-structure is widely distributed and remaining oil enriched in fluvial facies reservoir of Nm and Ng in Gaoqiannan area. On the statistics of Gaoqiannan within several layers in the three fault blocks, reserves of the micro- structure are 38.43% of the total reserves. Micro-structure characterization method is studied with the integration of geology, logging, drilling and development dynamic data. Two aspects of studies were carried on including micro-structural characterization and the relationship between micro-structure and remaining oil distribution. The major results are as follows.Taking both structure and deposition into consideration, the micro-structure is mapped. Three positive micro–structures, three negative micro–structures and micro-bevel are identified in the map. The three types of positive micro–structures includes micro-high point, micro-nose and micro- faulted nose structures while the three types of negative micro–structures are micro-low point, micro-groove and micro-faulted trough. The majority micro-structure is micro-faulted nose. Based on the above study, micro- structure top-bottom configuration mode is established. In this study, micro-faulted nose, which is the widely developed faults type, and the relationship between the micro-faulted nose's size and fault throw are analyzed.Relationship between micro-structure and remaining oil is studied with dynamic development data. It is concluded that: 1) positive micro–structures and top convex-bottom convex configuration mode are beneficial to remaining oil enrichment; 2) wells with high oil production locate in the area where positive micro-structure and central microfacies developed. 3) oil production of adjacent wells in the same sedimentary microfacies is very different due to different micro-structure types.