地学前缘 ›› 2009, Vol. 16 ›› Issue (4): 215-224.

• 论文 • 上一篇    下一篇

华北上地壳构造单元划分

  

  1. 1中国地震局 地质研究所, 北京 100029
    2中国地质科学院 地质力学研究所, 北京 100081

  • 出版日期:2009-08-01 发布日期:2009-08-01
  • 作者简介:李涛(1953—),男,副研究员,构造地质学专业,主要从事大陆变形过程构造及石油构造研究。 Email:litao1953@163.com
  • 基金资助:

    国土资源大调查项目(1212010633604)

Tectonic division of the upper crust of the North China Block.

  1. 1Institute of Geology, China Earthquake Administration, Beijing 100029, China
    2Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China

  • Online:2009-08-01 Published:2009-08-01

摘要:

利用天然地震数据分析研究得到的中地壳滑脱层的深度、活动方式、强度等结果,与重磁异常基底解译成果相结合,提出华北地区在中地壳位置发育有区域滑脱面,其特定壳层及深度位置决定了其在华北深浅构造关系转换中,起着“屏蔽”或联系的重要作用,而在华北伸展变形中是地块运动变形的底边界面。上地壳各个部分在沿其滑动时,因速度差、侧向约束条件等的不同,而派生出断叉线、横向调整断裂及相应的凸起、凹陷断块等次级单元。它们构成了华北上地壳基本构造单元,并直接控制着盆山空间分布、构造地貌单元发育。研究提出了华北上地壳构造单元划分方案:上地壳基底构造分为9个一级单元(Ⅰ~Ⅸ)和23个二级单元。其中一级构造单元为:Ⅰ阴山北部东西向区域凹陷断块;Ⅱ阴山—燕山区域凸起断块;Ⅲ太行山区域凸起断块;Ⅳ大别山区域凸起断块;Ⅴ渤海湾盆地断坳、断隆区;Ⅵ南华北盆地断坳、断隆区;Ⅶ鲁西区域断隆区;Ⅷ下扬子区域断坳、断隆区;Ⅸ鄂尔多斯区域断坳区。

关键词: 关键词:上地壳;伸展体制;滑脱层;构造单元;华北地块

Abstract:

By the analysis of natural earthquakes, we obtained the depth, the style of activation, and the strength of the detachment layer in the middle crust. Based on above study and combined with the interpretation of the gravity and magnetic anomalies of the basement of the study region, we propose that there is a regional detachment layer formed in the middle crust in the North China Block, and its depth determines the transition between the shallow and deep deformation in the study region. The detachment layer is the floor boundary of the deformation during the extension of the North China Block. When units of upper crust of the region slip along the detachment layer, owing to different velocities and boundary conditions, the derived cutoff lines, transverse faults and minor related highs and depressions are formed; all these are the basal tectonic units consisting of the upper crust of the North China Block, and they controlled the distribution of the basins and ranges and tectonic landforms basically in the study region. The division scheme of the upper crust in the North China Block is brought forward: there are 9 firstscale units (ⅠⅨ) and 23 secondscale units. Among them, the firstscale units are: Ⅰ EWtrending faulted block of the regional depression in the northern Yinshan; Ⅱ faulted block of YanshanYinshan regional high; Ⅲ faulted block of regional Taihangshan high; Ⅳ faulted block of regional Dabieshan high; Ⅴ faulted sags and uplifts in the Bohai Bay basin; Ⅵ faulted sags and uplifts of southern North China basin; Ⅶ regional faulted uplifts in west Shangdong; Ⅷ regional faulted sags and uplifts in the Lower Yangtze; Ⅸ regional faulted sag of the Ordos.

Key words:

Key words: upper crust; extensional setting; detachment layer; tectonic unit; North China Block

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