电成像测井在珠江口盆地西部沉积相研究中的应用

Application of Imaging Logging in Sedimentary Facies Study in the West of Pearl-river Mouth Basin

珠江口盆地西部主要由神狐隆起、琼海凸起和文昌A、B、C凹陷3部分组成,该区沉积环境复杂,储层横向变化大,给油田的勘探开发工作带来很大困难。利用电成像测井资料高分辨率、高直观性的特点,精确确定岩性界面,有效识别砾岩;并依据其所蕴涵的丰富的地质信息,识别出7种层理构造,以及冲刷面、波痕、钙质结核、生物构造等其他沉积构造,建立了4种沉积微相的识别模式,同时对研究区不同层段的古水流方向进行了分析。研究成果对该区沉积演化、物源方向分析起到了重要的作用,也对下一步勘探开发具有指导意义。

In the west of the Pearl-river Mouth Basin there were three parts,namely,Shenhu Uplift,Qionghai Uplift,and Wenchang Sag which included Wenchang A Sag,Wenchang B Sag and Wenchang C Sag.It was very difficult for the oilfield exploration and development due to complicated sedimentary environments and the large transversal change of reservoirs.Based on the characteristics of high resolution and visualization of imaging logging data,the lithologic interface was determined accurately,the conglomerate was identified effectively.Based on the abundant information contained in imaging logging data,7types of sedimentary structures,including bedding structures,scour surfaces,ripple marks,caliche nodules,bioturbation structures,etc.were recognized,four recognition patterns of sedimentary microfacies were built and paleocurrent directions of different formations of the target region were studied.The results not only play a key role on regional sedimentary evolution and source direction analysis but also guide the further oilfield exploration and development.