摘要
本文综合研究了山西断陷带垂直形变的空间分布特征及其与本区深、浅部结构,构造和地壳介质物性特征的关系;结合浅部地震地质和深部探测的研究结果,初步探讨了本区现代垂直形变的成因。研究结果表明:1.垂直形变测量揭示出山西断陷带的现代垂向构造活动具有明显的分段性。即晋北地区以北东至北东东向构造活动为主,晋南地区以北京东至近东西向构造活动为主,而中段则以北北东向构造活动为主;同时,也反映了浅部构造活动和地壳介质的物性特征对地壳形变的制约作用;2.山西断陷带内主要盆地的垂直形变与其深部上地慢局部隆起存在明显的相关性。上地幔的局部隆起作用是各主要盆地现今仍在下沉的主要原因,而下沉速度的大小与盆地内介质的力学强度有关;3.在地壳形变,地震预报及其相关的研究中,应该充分重视地壳介质的物质组成及其物性特征的不均一性。
In this paper,the author has synthetically studied the spatial distribution of the vertical deformation in Shanxi fault subsided zone as well as its relation to the shallow and deep structrues of the region. The mechanical and structural origin of the recent vertical deformation of the region has been discussed based on seismo'geologic data and deep sounding information. The results reveal the following aspects; (1)The results of leveling show that the recent vertical tectonic movement in Shanxi fault subsided zone is characterized by segmentation, i, e. the northern, southern and central parts of the fault subsided zone are dominated by NE to ENE,ENE to WE, and NNE-trending tectonic movement respectively. It reflects the control of the shallow structural movement on the ground deformation. (2)The vertical deformation of the main basins closely related to the local upwelling of the upper mantle. In Shanxi fault subsided zone, it is this local upwelling of the upper mantle that results in the subsidence of the basins. The rate of subsidence depends on the mechanical strength of media within the basins. (3)The study of the anisotropy of the crustal medium and its physical properties is of importance to the studies of crustal deformation and earthquake prediction and the studies related to them.
出处
《中国地震》
CSCD
北大核心
1993年第4期327-333,共7页
Earthquake Research in China
关键词
山西
断陷带
地壳
垂直形变
成因
Shanxi fault subsided zone Vertical crustal deformation Origin
