精细古地貌恢复指导隐蔽油藏勘探发现

Exploration Discoveries of Elusive Reservoirs Using Detailed Paleogeomorphology Reconstructions

吕振宇 张新涛 边立恩 王军 刘腾

LÜ Zhenyu ZHANG Xintao BIAN Lien WANG Jun LIU Teng

中海石油(中国)有限公司天津分公司渤海石油研究院, 天津 滨海新区 300459

Bohai Oilfield Research Institute, Tianjin Branch, CNOOC China Limited, Binhaixinqu, Tianjin 300459, China

精细恢复陡坡带下降盘的微古地貌，探讨沉积期古地貌对沉积的控制作用。基于平衡剖面原理，提出构造沉积恢复法：选取合适机制，对Q构造三维构造模型进行构造恢复和地层压实恢复，减小晚期构造运动对边界断层下降盘同沉积期古地貌的影响。实例对比表明，构造沉积恢复法较传统的残余厚度法能够更准确地刻画盆地同沉积期的微古地貌特征。实际钻探结果证实，运用该方法恢复古地貌可以更精准地预测沉积体系和储层的分布，预测结果与实钻吻合良好，为渤海湾盆地Q构造区大型油田的发现提供了有力支持。

Using detailed reconstructions of micro-paleogeomorphology in subsidence basins with steep slopes, we investigated the mechanisms controlling sedimentation. Based on the Balanced Cross Section principle, a tectonic-sedimentation reconstruction method is proposed, and a suitable mechanism chosen to reconstruct tectonics and compaction of formations in a three-dimensional Quaternary tectonic model. The mechanism reduces the effects of late tectonic activities on the paleogeomorphology of subsidence basins of border faults during syndeposition. A comparison between results and observations indicates that the tectonic-sedimentation reconstruction method can more accurately depict the micro-paleogeomorphological characteristics of basins during syndeposition than the traditional residual thickness method. Drilling and monitoring data verify that application of the tectonic-sedimentation reconstruction method to reconstruct paleogeomorphology can better predict distributions of sedimentary systems and reservoirs. The predictions are consistent with the actual drilling results. This provides strong evidence for the potential for discovering large oilfields in the Quaternary tectonic region in the Bohai Bay Basin.

10.11885/j.issn.1674-5086.2017.07.21.01