摘要
徐水凹陷处于渤海湾盆地西部,西侧以太行山山前断层为界与太行山隆起隔开。为了全面认识徐水凹陷的形成过程,更好地服务于区内的油气勘探工作,综合利用研究区内的钻井和地震资料,对徐水凹陷的地质结构进行系统研究。通过对凹陷内的地震剖面进行精细解释,刻画区内主要断裂的发育特征;运用平衡剖面技术,恢复了徐水凹陷古近纪以来的演化过程。结果表明,徐水凹陷新生界内发育古近系底部和新近系底部2个区域性不整合面,据此划分出3套构造层,即基底构造层、古近系构造层和新近系-第四系构造层。受控于NE向的太行山山前断层和NWW向的涞水断层,徐水凹陷表现出西断东超和北断南超的构造格局。研究认为,新生代以来徐水凹陷的构造演化经历了强烈断陷阶段、断陷持续发育阶段、断-拗过渡阶段和拗陷阶段。凹陷内的断陷活动于古近纪早期开始发育,持续至渐新世晚期,并具有幕式活动的特征。
The Xushui Sag,located in the western Bohai Bay Basin,is separated from the Taihang Mountain uplift by the Taihang Mountain piedmont fault to its west.In order to improve the understanding of the formation of the sag and facilitate petroleum exploration in the region,we systematically studied the geologic architecture of Xushui Sag through the drilling and seismic data.Characteristics of the major faults in the study area were revealed based on fine interpretation of the seismic profiles within the sag.The post-Paleogene tectonic evolution process of Xushui Sag was reconstructed via the balanced cross-section technique.The results show that there are two regional unconformities in the Cenozoic in the Xu-shui Sag,one being at the base of the Paleogene and the other being at the base of the Neogene.According to these two unconformities,three tectonic layers,namely the basement,the Paleogene and the Neogene-Quaternary layers,are subdivided.The structural framework of the study area with faults occurring in its west and north and overlapping occurring in its east and south,is controlled by the NE-trending Taihang Mountain piedmont fault and the NWW-trending Laishui fault.This study demonstrates that the post-Cenozoic tectonic evolution of the study area can be divided into four stages:intense rifting stage,continuous rifting stage,transitional stage from rifting to depression and depression stage.Rifting in the Xushui Sag,characterized by episodic activities,began to grow in the Early Paleocene and proceeded until the Late Oligocene.
作者
单帅强
张煜颖
张锐锋
Shan Shuaiqiang;Zhang Yuying;Zhang Ruifeng(School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China;Huabei Oilfield Company Ltd.,PetroChina,Renqiu,Hebei 062552,China)
出处
《石油与天然气地质》
EI
CAS
CSCD
北大核心
2018年第5期1037-1047,共11页
Oil & Gas Geology
基金
国家重点研发计划项目(2017YFC0601405-03)
关键词
地质结构
构造层
构造演化
太行山山前断层
冀中坳陷
渤海湾盆地
geologic architecture
tectonic layer
tectonic evolution
Taihang Mountain piedmont fault
Jizhong Depression
Bohai Bay Basin