断陷盆地复杂断裂区古构造恢复——以渤海湾盆地济阳坳陷渤南洼陷沙四下亚段为例  

Restoration of ancient structures in complex fault areas of faulted basins: Taking the lower section of the fourth member of Shahejie Formation in the Bonan Sag of Jiyang Depression of Bohai Bay Basin as an example

作　　者：张鹏飞 刘金华 孟涛[1] 姜超[1] 彭湃 Pengfei ZHANG;Jinhua LIU;Tao MENG;Chao JIANG;Pai PENG(Exploration and Development Research Institute of SINOPEC Shengli Oilfield Branch,Dongying 257100,China;School of Geosciences and Technology,Southwest Petroleum University,Chengdu 610500,China;Geological Exploration and Development Research Institute of Chuanqing Drilling Engineering Company,Chengdu 610051,China)

机构地区：[1]中国石化胜利油田分公司勘探开发研究院,山东东营257100 [2]西南石油大学地球科学与技术学院,四川成都610500 [3]川庆钻探工程公司地质勘探开发研究院,四川成都610051

出　　处：《天然气地球科学》2024年第11期1973-1982,共10页Natural Gas Geoscience

基　　金：国家科技重大专项“渤海湾盆地精细勘探关键技术”(编号:2016ZX05006)资助。

摘　　要：古构造对油气储层的发育特征、油气生烃和成藏等具有控制作用,对其开展研究具有重要意义。但是在断陷盆地复杂断裂区正断层的大量发育增加了三维古构造恢复难度,在断陷盆地古构造研究中开展剥蚀量恢复、去压实校正、断层影响等方面研究仍存在困难。针对研究区目的层非均质性较强,现有的孔隙度恢复压实校正方法存在孔隙度与深度关系过于复杂、应用效果较差等问题,利用地层压实校正、层拉平古构造恢复、3D成图等方法对渤海湾盆地济阳坳陷渤南洼陷沙四下亚段进行古构造恢复研究。创新性引入密度测井(DEN)数据,利用地层物质守恒原则,提出一种可操作性较强的压实校正研究新思路;并基于层拉平古构造恢复法,通过断层影响校正与视厚度恢复等研究获取地层厚度,利用剥蚀量、压实校正、构造平衡剖面分析方法获取原始地层厚度,最后利用3D成图软件编绘古构造三维空间形态图,新古构造图可以更真实地反映出沙四下亚段沉积时的地貌特征。该古构造恢复方法是一种可操作性较强的适应于断陷盆地复杂断裂区的三维空间古构造恢复法。The study of ancient structures is important for oil and gas exploration and development,as it plays a controlling role in the development characteristics of oil and gas reservoirs,hydrocarbon generation,and reservoir formation.However,the extensive development of normal faults in complex fault areas of faulted basins increases the difficulty of three-dimensional ancient structure restoration.There are still certain problems in the study of ancient structures in faulted basins,such as the restoration of erosion,fault removal,and compaction correction.In response to the strong heterogeneity of the target layer in the research area and the poor effectiveness of existing porosity recovery and compaction correction methods due to the complex relationship between porosity and depth,this study uses methods such as stratigraphic compaction correction,layer flattening ancient structure recovery,3D mapping,etc.to study the ancient structure recovery of the lower section of the fourth member of Shahejie Formation(Es 4 x)in the Bonan Sag of Jiyang Depression,Bohai Bay Basin.This study innovatively introduces density logging(DEN)data and proposes a new approach for compaction correction research using the principle of conservation of formation materials;and based on the layer flattening ancient structure restoration method,the thickness of the strata is obtained through research such as fault removal and apparent thickness restoration.The original thickness of the strata is obtained using methods such as erosion amount,compaction correction,and structural equilibrium profile analysis.Finally,a 3D mapping software is used to compile a three-dimensional spatial morphology map of the ancient structure.The new ancient structure map can more accurately reflect the geomorphic characteristics of the sedimentation under the fourth sand layer.Thus,a three-dimensional spatial paleotectonic restoration method suitable for complex fault zones in faulted basins was proposed.

关 键 词：古构造 压实校正 构造平衡剖面 沙四下亚段 渤南洼陷 

分 类 号：TE122.3[石油与天然气工程—油气勘探]