【作者】 秦小军；

【导师】 周硕愚；

【作者基本信息】 中国地震局地质研究所 ， 固体地球物理， 2006， 博士

【摘要】 高、新技术在地学中的应用,已能够从三度空间、动态地探测地球系统的结构和运动形态,使地球科学的理论研究能以踏实的实测资料为基础,从而促进地球各层圈运动的研究从定性向定量,从局部向全球,从三维空间向四维时空,从各向同性向各向异性、从线性向非线性介质发展。新探测技术为地球科学研究的发展提供了资料保证,而地球科学的理论研究也将会对新技术的发展和应用提出更多、更新的要求。因此如何适应探测技术的革命,是地球科学理论研究面临的最重要的挑战之一。大量地球系统数据的收集、储存、处理和分析,对数据信息系统网络的硬件和软件提出了新的要求,这已成为当前地球科学研究的基础性工作之一。以空间大地测量为标志的现代大地测量学正进入一个学科发展的新阶段,其学科性质将从工程应用为主转向地球科学的基础学科。目前观测技术和观测工作发展较快,理论方法尤其是真正用于地学基础研究的部分相对滞后。作者试图将数学力学的新方法引入块体现今运动模型研究之中,在理论方法方面做一些工作,促进地壳运动与动力学基础问题研究,使观测技术更好地为地球科学服务,进而为地震大形势预报开拓新的途径,也希望能对强震发生理论,大陆动力学研究等地球科学的发展有所裨益。本文从空间大地测量学、动力大地测量学、地质学和地球物理等多学科综合应用的角度出发,通过引入数学力学的新方法:非连续变形分析方法(DDA),结合空间大地测量取得的大量实测数据,以及地质,地球物理的研究成果构建具有明确力学意义的构造块体及边界带系统运动变形模型,研究构造块体系统运动在不同层次,不同尺度上的运动学特征,勾划构造块体系统的运动方式,活动规律、幅度与过程,探索构造块体边界条件的合理处置,提出了建立现今地壳构造块体系统运动变形定量模型的新方法。在此基础上,分析研究了南天山地区现今地壳运动特征和构造应力场特征,模拟研究了该地区伽师强震群的发震机制。并将空间大地测量GPS数据观测和模拟的结果与构造地质、震源机制,深部细结构探测、构造物理实验及其它大地测量等研究成果进行相互印证分析,讨论了南天山现今地壳运动快速缩短、活动断裂和伽师强震群发震机制等若干问题。为此,主要开展了以下几方面的工作:(1)从二维DDA的基本理论出发,在较严谨的运动学、力学基础上,推演利用空间大地测量数据确定顾及块体及边界带系统弹性变形和不同块体间非均匀性运动定量模型的基本方程和方法。包括块体自由度与系统自由度的考虑和选定,运动方程的建立,运动学模型的正、反演算法。(2)研究将DDA方法应用于数十乃至数百公里的大尺度构造块体系统时的精度控制因素及其必要的调整研究。(3)根据实际GPS数据和研究区域的情况研究DDA方法的荷载加载方式及其效果。更多还原

【Abstract】 Applications of high and new technology in geosciences make it capable to study dynamically the structure and movements of the earth system in three-dimensional space. Since theoretical studies of geosciences have a steady groundwork, the research of all spheric layerss of the earth has been promoted greatly from qualitative to quantitative manners, from local scales re to global scales r, from isotropy to anisotropy, and from liner to non-liner features. The appearance of new exploration technology provided guarantee for plenty of data while theoretical studies of geosciences raise more and higher demands for the development and application of new technology. Acquisition, storage, processing and analysis of vast observational data bring forward new requirements to hardware and software for data information system networks, and it becomes one of basic work for current geoscience research.The modern geodesy has entered into a new stage marked by the development of space geodesy. Its focal points have shifted from engineering applications to basic research. However, observational technology is developing faster than the theoretical research of earth sciences. This thesis makes an attempt to introduce new algorithms from mathematical mechanics to establish new present-day block movement models, and perform theoretical research work on geodynamics, so that the observation technology can serve better for theoretical research of geoscience, and to find a new way for prediction of general trends of earthquakes. The author also hopes the results can be useful for studies of mechanisms of large earthquakes and continental dynamics.This thesis is based on integrated usage of multi-disciplinary geosciences inclduding space-geodesy, dynamic geodesy, geology and geophysics. By introducing a new algorithm of mathematical mechanics - Discontinuous Deformation Analysis (DDA), and combining mass of space-geodesy observational data with some results from geology and geophysics, this work establishes a tectonic block movement and deformation model with explicit mechanical meaning. Then it analyses kinetic characters of the tectonic block system movement at different levels and different scales, and describes both the kinematics mechanism and the amplitude of the tectonic block system. A new method is suggested to establish quantitative models for current crustal motions and deformation of tectonic systems. Furthermore, this thesis analyses the characters of the current crustal movement and tectonic stress field in the southern Tianshan Mountains area, and performs a simulation research of earthquake mechanism of the Jiashi major earthquakes.更多还原