Reservoir Characteristics and Fracture Prediction of Buried Hill A in Pinghu Slope of Xihu Sag

As one of the hydrocarbon-rich sags in East China Sea, Xihu Sag has good exploration potential in the buried hill area. Buried hill "A" is located in Pinghu slope of Xihu Sag, the reservoir of the inner buried hill has complex features, strong heterogeneity and stacking elastic parameters. The conventional methods cannot accurately describe the buried hill reservoir, which restricts the exploration process of the buried hill. In this artical, the internal structure and reservoir types of the buried hill are analyzed based on the utilization of drilling, rock core, analysis assay and seismic data. Pre-stack azimuthal anisotropy and forward simulation methods are used to predict high quality reservoir in the buried hill under the guidance of geological model. It is considered that buried hill "A" reservoir has a typical dual structure in the vertical direction, which is divided into the weathering zone and the internal fracture zone from top to bottom. Furthermore, the internal fracture zone is divided into strong and weak zones. The fracture prediction of pre-stack azimuthal anisotropy shows that the reservoir of the weathering fracture zone is better than that of the inner fracture zone, and the reservoir of the buried hill wing is better than that of the buried hill top. The weathering fracture zone of buried hill "A" wing is the favorable exploration direction.