高精度古地貌恢复技术及应用——以辽西凸起南段东营组二段下段为例

辽西凸起南段东营组二段下段发育大型岩性-超覆圈闭，储层发育程度以及分布范围是本区油气富集的主控因素。以油组为单位在低勘探程度区开展高精度古地貌恢复，通过剥蚀量恢复，结合埋深和地震响应特征对原始地层厚度进行了压实恢复，并运用岩性、沉积相以及地震响应特征等对该地区进行古水深校正。通过对研究区沟谷的横截面积及延伸长度定量分析，下切沟谷沿地貌形态和地形坡度由高至低，依次发育V型、U型、W型，其发育横截面积和输砂能力依次降低，且不同时期沟谷形态和发育位置的迁移控制了沉积体系发育特征。精细刻画了不同时期储层分布和沉积体系演化特征。

High Precision Paleotopography Restoration Technology and Its Application:Taking the Second Member of Dongying Strata in the South of Liaoxi Uplift as an Example

Large scale of lithological overlap traps are developed in the second member of Dongying Formation in the south of Liaoxi uplift. Development degree and distribution of reservoir are the major factors controlling oil and gas accumulation in the study area. In areas of low exploration prospects, high precision restoration of ancient landform is utilized in each oil group units. Based on restoration of denudation, burial depth and seismic respondence features, primary strata thickness is restored. Paleo water depth is recovered via lithology, sedimentary facies and seismic reflection. Through quantitative analysis of cross section area and extending length of valleys, ancient landform of three kinds of incised valleys are recognized. The gradient of ancient landform, cross section area and sand transporting capacity are reduced from V shape, U shape to W shape incised valley respectively. Shapes and locations of valleys in different periods control development of sedimentary systems. We elaborately depict reservoir distribution and sedimentary evolution features in different periods.