节点文献
黄骅坳陷构造变形格局与演化过程分析
Deformation Framework and Evolution of the Huanghua Depression,Bohai Gulf
【摘要】 本文以覆盖全区的3D和2D地震剖面的地质构造解释为基础,详细描述和分析了黄骅坳陷的基底和盖层结构构造及其演化,在黄骅坳陷基底内识别出了印支期东西向展布的大型褶皱-冲断构造和燕山主期NNE向展布的大型褶皱-冲断构造,认为黄骅坳陷中的歧口凹陷是在印支期古背斜的基础上经过新生代的伸展裂陷活动负反转而形成的断陷型盆地;确定出黄骅坳陷中、北区陆上新生代盆地结构表现为NE向延伸的、西北断东南超的多米诺式半地堑系结构,而在海域地区则表现为近东西向展布的规模巨大的复式地堑型结构;提出沧东断层延伸到黄骅坳陷中的板桥凹陷的北部,其断距已经逐渐减小,并与北塘次凹西斜坡发育的茶淀断裂以构造转换带方式衔接。论文还以盆地内的大型断裂系统的活动性和盆地沉降史的定量分析为基础,将黄骅坳陷新生代同裂陷阶段划分出三个幕次的演化过程,并发现从裂陷Ⅰ幕到裂陷Ⅲ幕盆地的沉积-沉降中心经历了由南向北、由陆向海的规律性迁移。根据控制沉降中心迁移的构造应力场,结合区域渤海湾盆地的基本特征,提出斜向拉分盆地模式来解释黄骅坳陷,乃至渤海湾盆地孔店组-东营组沉积期间的发育演化机制。
【Abstract】 Based on the geological structure interpretation of the 3D and 2D seismic profiles covering the whole study area in the Huanghua depression,the architecture and evolution of the basement and cover of the basin were described and analyzed in detail.The huge Indosinian E-W trending thrust-fold structure and the Yanshanian NNE trending thrust-fold structure were also identified.It is proposed that the main Qikou sag is a rifting basin resulted from negative inversion of the Indosinian uplifting paleo-anticline.The architecture of land in the north and middle part of the Huanghua depression appears as NE striking domino style half graben system,which was faulted at the northwest margin and overlapped at the southeast slope.The offshore part of the basin is characterized by a huge complex graben of nearly W-E striking.The throw of the Cangdong fault,boundary fault of the basin,decreases gradually from south to north,and disappears to the north of the Banqiao sag,and linked with the Chadian fault by the structure transitional zone at the west slope of the Beitang sag.From the quantitative analysis of the activity of the main fault systems and subsidence history of the basin,the Cenozoic synrifting evolution of the Huanghua depression was divided into three episodes.From the episode I to episode II,the depocenter and the subsidence center migrated northwards from the onshore to offshore.Finally,combining analysis of the tectonic stress field involving the migration of the subsidence center and the regional geological features of the Bohai bay basin,the transtensional basin model is preferred to interpret the evolution of the Huanghua depression and the deforming mechanism of the Bohai bay basin during the deposition of the Kongdian Formation(Ek) and Dongying Formation(Ed).
【Key words】 Huanghua depression; Qikou sag; Cangdong fault; transtensional basin; negative inversion basion;
- 【文献出处】 大地构造与成矿学 ,Geotectonica Et Metallogenia , 编辑部邮箱 ,2010年04期
- 【分类号】P542
- 【被引频次】54
- 【下载频次】1245