C51井区葡萄花储层薄砂体展布地震精细刻画

C51井区葡萄花储层为三角洲前缘沉积，从上至下发育PⅠ1、PⅠ2两套砂组，平均砂岩厚度分别为2、5m，砂体横向分布局限，现有地震资料的分辨率不足以区分两套砂组，虽然钻井资料能够准确识别单砂体，但无法刻画井间砂体变化。为此，通过精细对比研究区内18口井钻遇的砂体，掌握葡萄花储层砂体的空间展布规律，作为评价、优选地震属性切片的参考依据；从目的层段的连续沿层切片中确定体现砂组展布特征的反射时间；依据选定切片对应时间确定砂组的地震属性提取窗口，优选地震属性；基于地震属性平面图，确定砂组的沉积微相；在砂组展布和沉积微相约束下优选参数，开展地质统计学反演，提高垂向分辨率，精细刻画砂组的空间展布。预测结果精细刻画了两套砂组的空间展布，并且认为PⅠ2的砂岩厚度较大，适合储气库建设。

Seismic fine depiction of the thin sand distribution of the Putaohua Reservoir in the Well C51 Area

The Putaohua Reservoir in the Well C51 Area is of delta-front facies, and 2 sand groups (PⅠ1 and PⅠ2) are vertically developed with the average thicknesses 2m and 5m respectively.Although these sand groups are clearly distinguished on the well drilling data, their distribution cannot be identified on seismic data due to its low resolution.To solve the problem, seismic information and attributes are selected based on the sand groups of 18 wells.Sand group reflections are determined at wells and traced along horizons on seismic slices.Then seismic attributes of sand groups are extracted and optimized.After that, the attributes are conversed to sedimentary micro-facies, and the constrained sedimentary micro-facies geo-statistical inversion is carried out to increase the vertical resolution.Finally, the distribution of 2 sand groups is predicted.According to our prediction, PⅠ2 is thicker, and is suitable for gas base building.