塑性流动网络控制下华北地区构造应力场与地震构造  

TECTONIC STRESS FIELD AND SEISMIC TECTONICS CONTROLLED BY PLASTIC-FLOW NETWORK IN NORTH CHINA

作　　者：王绳祖[1] 张流[1] 

机构地区：[1]中国地震局地质研究所,中国地震局构造物理开放实验室,北京100029

出　　处：《地震地质》2002年第1期69-80,共12页Seismology and Geology

基　　金：国家重点科技项目 (96 9130 90 2 0 30 2 );中国地震局地质研究所论著 2 0 0 2B0 0 10

摘　　要：文中所述华北地区位于中东亚塑性流动网络系统的东部 (偏北 ) ,在岩石圈下层内含右向和左向塑性流动网带多条 ,受其控制 ,在其上方多震层内形成地震带 ,并导致上层构造应力场在总趋势上与下层基本保持一致。发震断裂以不同交角沿网带展布 ,组成地震构造带 ,其中少数地震构造带的视成熟度较高 。The tectonic stress field and seismic tectonics in the North China region are investigated in terms of the 'plastic-flow network and multi-layered tectonic deformation' model for continental dynamics. It is presented in the model that in consideration of the basic state of the transition of deformation regime from brittle to ductile with increase of the depth, the lithosphere is divided into several tectonic deformation layers, i.e. the ductile lower lithosphere (including the lower crust and lithospheric mantle) with netlike plastic-flow and the brittle upper lithosphere (including seismogenic layer and the shallow crust) with shear and tensile fractures, as well as the transitional layers (i.e. low-velocity / high-conductivity layers) discontinuously distributed between those mentioned above; the long-range transmission of driving force applying at continental plate boundary is carried out mainly by the netlike plastic-flow in the lower lithosphere, which controls intraplate tectonic stress field, tectonic deformation and seismic activities; the plastic-flow network, which is composed of two families of plastic-flow belts (i.e. ductile shear belts) intersecting each other, can be referred to as a 'slip-line' network developed under large deformation condition. The previous study indicates that the plastic-flow network system developed under the compression at the Himalayan driving boundary spreads over a broad area in central-eastern Asia. The North China region discussed in this paper is located in the northeast part of this network system. The directions of the maximum compressive stresses in the lower lithosphere can be estimated from the lines bisecting conjugate angles of the network. Comparing these directions with those in the seismogenic layer inferred using focal-mechanism solutions, it is shown that both of them are identical with each other in general tendency, indicating that the stress field in the upper layer is controlled by that in the lower layer; meanwhile, the directions of the stress vec

关 键 词：塑性流动网络 构造应力场 地震带 地震构造带 视成熟度 华北地区 

分 类 号：P315.2[天文地球—地震学]