汇集爆破地震大数据对华北克拉通中西部不同构造区域壳幔结构地震学意义的研究

项目名称： 汇集爆破地震大数据对华北克拉通中西部不同构造区域壳幔结构地震学意义的研究

项目编号： No.41474077

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 天文学、地球科学

项目作者： 赵金仁

作者单位： 中国地震局地球物理勘探中心

项目金额： 95万元

中文摘要： 华北克拉通中西部地处不同构造区过渡带，结构复杂。利用该区近30年来完成的20余条二维探测剖面获得的成果与观测资料；选择近几年地震剖面实施的30余次大药量爆破在甘肃、山西、宁夏等6省台网获得的观测资料进行全面的汇集采样。通过对已有多条剖面地壳模型统一地壳分层模式和所有观测资料的统一处理，统一构建三维地壳模型。结合二维、三维地壳模型共同对华北克拉通中西部不同构造区地壳深浅部结构的差异及其地震学特点进行研究。在鄂尔多斯西部选择3条典型剖面对其P、S波速结构、Q值结构进行综合研究，从不同层面、多视角的揭示鄂尔多斯西部不同构造过渡带地壳结构的复杂性与速度结构非均匀性的地震学证据。同时对复杂构造区和大震区结构的复杂性、物性结构的横向非均匀性及其地震学意义给出一些综合解释结果。为深入认识地处青藏高原东北缘的鄂尔多斯西部这一特殊的构造过渡带地壳深、浅部复杂构造环境所包含的动力学意义提供深部地震学基础。

中文关键词： 汇集爆破地震大数据；华北克拉通中西部；不同区域三维地壳图像；P；S波速与Q值结构；复杂构造带地震学意义

英文摘要： The Midwest of North China craton is located in the transition zone of different tectonic areas, and there are the very complicated structures. Those structures are researched using the DSS data and existing results of over 20 2-D profiles completed in nearly 30 years. DSS data observed at fixed network in Gansu-Shanxi-Ningxia regions in recent years,with over 30 times large dose of blasting, are selected and sampled. The unified stratification for the over 20 2-D crustal structure model is processed. Based on the unified stratification model, a 3-D crustal structure model is constructed by unified processing of DSS data. In combination of 2-D and 3-D crustal structure model, the structure differences and seismology characteristics in different tectonic zones of Midwest in North China craton are studied. The P- and S- wave velocity and Q value are comprehensively studied through three typical 2-D profiles in Western Ordos, so that the structural complexity and heterogeneity of velocity structure along the transition zone in different tectonic units of Western Ordos are revealed from different perspectives. At the same time, the complexity of complex tectonic belts and great earthquake belts, lateral heterogeneity of physical property structure, and its significance in seismology are interpreted comprehensively. The deep basis of seismology are provided for further understanding deep dynamics of crust complex tectonic environment of this special structure transition zone in Western Ordos which is located in the northeastern margin of Tibet Plateau.

英文关键词： DSS data;the Midwest of North China craton;3-D crustal structures in different regions;P- and S- wave velocity and Q value;Seismological significance in complex tectonic belts