断层成核与失稳过程热场演化的实验研究

项目名称： 断层成核与失稳过程热场演化的实验研究

项目编号： No.41474162

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： 陈顺云

作者单位： 中国地震局地质研究所

项目金额： 95万元

中文摘要： 强烈地震源于断层的突发失稳，断层从准静态到动态滑动经历了怎样的过程，能否尽早发觉是地震学一个倍受关注的问题。通常认为，地震波释放的能量只占小部分，大部分能量转化为热能（80-90%）。通过条件可控的实验手段，弄清断层作用不同阶段生热效应的量级、演化过程和物理机制及其影响因素。反过来，借助热效应的分析，有可能帮助我们识别出断层成核以及失稳阶段的时空演化特征。本项目中，拟以实验为主，开展下列工作:(1)生热机制的参数化与定量化研究;(2)研究断层成核初始、扩展过程热场时空演化特征; (3)探索成核向失稳转换的热场标志;(4)研究断层失稳滑动阶段的热场特征;(5)以实验结果为基础，开展温度场演化数值模拟，结合野外断层地温观测开展综合分析。最终，通过项目的执行，弄清断层局部预滑、扩展及其失稳滑动的热场演化规律，识别出成核起始、扩展及其向失稳转换的热场标志,为地震热前兆与同震热效应分析提供物理依据。

中文关键词： 断层成核；断层失稳；热场标志；时空演化；生热机制

英文摘要： A strong earthquake is thought of the result of abrupt instability of fault. What does a fault experience during the processes from quasi-static to dynamic slide? Whether can these processes be found as early as possible? These problems are of great importance in earthquake research. It is generally accepted that only a small amount of energy is released by seismic wave, and most of the energy is converted to heat (80-90%). The magnitude of heat effect, its evolution, its physical mechanisms and its influencing factors at different stages of faulting may be obtained with the experimental method which conditions can be controlled. Conversely, with the analysis of thermal effects, it is possible to help us identify the fault nucleation and its space-time evolution and the instability of fault. The project is intended to undertake the following tasks:(1) develop the mechanisms of generating heat of faulting; (2) investigate the thermal feature of the initial nucleation and its evolutional processes; (3) identify space-time thermal mark from nucleation to the instability of fault; (4) analyze thermal characteristics during the instability of fault; (5) based on the experimental results, the evolution of the temperature field is numerically simulated, and then to combine with field observations of ground temperature along fault, a comprehensive analysis will be carried out. Eventually, through the implementation of the project, the principle on the thermal field signal from the local pre-slip segment to the instability of fault is obtained, and especially, the thermal marks on nucleation initiation and its conversion into the instability of fault are found. These can provide a physical basis for detecting earthquake thermal precursory and analyzing co-seismic thermal effects.

英文关键词： fault nucleation;fault failure;thermal mark;space-time evolution;mechanism of generating heat