1. School of Geosciences, China University of Petroleum (East China), Qingdao, Shandong 266580, China;
2. College of Earth Sciences and Engineering, Shandong University of Science and Technology, Qingdao, Shandong 266590, China;
3. Zhanjiang Branch, CNOOC, Zhanjiang, Guangdong 524057, China;
4. Dongxin Oil Production Plant, Shengli Oilfield Branch Co., SINOPEC, Dongying, Shandong 257000, China
Abstract:It is very difficult to perform sedimentary micro-facies characterization with seismic in Wenchang 13-1 Oilfield, Zhujiangkou Basin due to sparse well net, different sand thickness, and different depositional micro facies. Here we propose an approach for sedimentary micro facies characterization in the area. First we determine sedimentary micro facies types based on core data. Then we characterize sedimentary facies with seismic attributes and seismic facies analysis. After that we develop a new seismic attribute named “logarithm of standard seismic arc length”, and use it for sandstone thickness quantitative prediction to build seismic facies models for sand flat main body and sand flat edge. Finally planar distribution of sandstone thickness and seismic facies are used to confirm sedimentary micro facies boundaries. It is concluded that after a sedimentary evolution sequence of “mud flat, mixed flat and sand flat”, sand flat main body distributes mainly in the middle and west of the study area, and sand flat edges are developed as thin inter-beds in the whole area. This study provides good geologic basic knowledge for further oil development.