南华北块体及邻区地质结构构造研究进展

Research progress of geological structure in the South north China and adjacent areas

本文通过对前人在南华北块体及邻区所做的地质及地球物理勘探研究成果进行了综合分析,发现一些构造单元的划分、岩石圈变形机制及应力变化过程等问题存在争议,甚至同一地区不同研究者研究结果相互存在着矛盾和差异性.为此,本文对上述有差异和争议的研究进行了系统详细的调研,认为在南华北及邻区地块范围内地表地貌整体呈现隆坳相间的形态,深部构造较为复杂,从地表地势到岩石圈构造都经历了不同程度多种方式的变形和多期演化.横向上岩石圈构造在原有基础上变形调整,岩石圈厚度具有南厚北薄、西厚东薄的特点,是受到NW向和NE向两组应力作用的结果,构造主体有序分布,研究区域被两个方向的断裂切割和围陷,进而划分为不同构造单元,构造单元呈长条状间隔分布,次级构造单元内部又可划分为更小的单元,具有分层次变形特征.在演化过程中,研究区域经历了多期构造运动变形,后期运动继承并改造了先存构造,发育有切穿地壳的深大断裂,这些先存大断裂影响并控制了区域隆坳发育,在浅部分散为多条小断裂,对区域中小地震的发生具有重要的影响.本文在分析横向及纵向大地构造特点的基础上,系统梳理了区域内重要构造单元,分南北两侧调研了区内断裂的发育情况,为后续该区相关地质研究提供借鉴和有价值的参考.

Based on the previous geological and geophysical exploration research, we make a comprehensive analysis in the South north China and adjacent areas. It still remain controversial in many aspects, such as lithosphere deformation mechanism and stress change process. Even in the same region, there are contradictions and differences between the research results. The surface topography in this region certain regulation with the interlacing distribution of uplift area and depression. From the surface topography to the lithosphere basement structure has undergone different evolution in many ways, which cause complex deep structure. From a horizontal perspective, lithosphere basement structure is deformed and adjusted on the original basis, which is formed ordered distribution structure under stress in NW direction and NE direction. From south to north, the characteristic of the lithosphere thickness is thick and thin, which is the same in west to east. The region is divided into different structural units. By analysis of the structure attribute, we obtained that it has fractal deformation characteristics in this area. More specifically, the sub-structural unit can be subdivided into smaller units. Over a long period of geological evolution, multi-stage tectonic deformation has took place in this region, which caused the preexisting structure is inherited and reconstructed. There are deep and large fractures extend to the crust, which affected and controlled the development of regional uplift depression. In the shallow part, the deep large fault has several small faults. It has an important influence on the occurrence of small and medium earthquakes in South north China and adjacent areas. A group of deep-shallow crust deformation affected and controlled the development and formation of regional uplift and depression. Based on the analysis of the characteristics of transverse and longitudinal geotectonic structures, we investigated the development of faults’ research in the area on the north and south sides and analyzed the important structural units in the region. This paper will review the research achievements and progress of the geological structural characteristics, and it can provides references for subsequent related research in the study area.