【摘要】 地震预测是世界性科学难题.地震现象虽然复杂其物理实质倒是明确:地震就是地壳块体的快速剪切脆断.相应地,地震的孕育过程就是震源区介质的损伤、演化,并最终导致破坏的过程,这一过程主要是力学过程.抓住这一点就抓住了问题的物理本质.但是,在研究地震预测时遇到的力学问题和通常的(工程)力学问题有所不同.根据地震问题的特点,紧扣地震孕育过程的物理本质,提出了加卸载响应比这一地震预测新思路.文中介绍了加卸载响应比理论的基本科学问题,包括如何对地壳加载/卸载,如何选择适当的地球物理参数作为响应量,以及怎样定义加卸载响应比.用实验研究、数值模拟和理论分析3种基础研究手段,揭示了地震孕育过程中加卸载响应比共同的演化规律:孕震初期加卸载响应比在1附近涨落,之后上升至峰值点,地震不在峰值点发生,而是在下降过程中发生.从峰值点到地震发生这段滞后时间称为T2,T2和震级有关.为了预测地震,必须在全国范围内作加卸载响应比的时空扫描.在时空扫描基础上,结合量纲分析,更多地考虑当地的地球物理条件,拟定了全面预测未来地震的时、空、强的思路.回顾了用这种思路进行地震预测实践的历程.更多还原

【Abstract】 Earthquake prediction is a scientific challenge to the world’s scientists. Being a complex natural phenomenon, earthquake has a quite clear physical nature, that is, a rapid shear fracture in the crust. Accordingly, earthquake preparation is the damage evolution process for the crust media, which eventually leads to catastrophic fracture. This is mainly a mechanical process. Considering this point and grasping the physical nature of seismogenical process, we have put forward a new approach to earthquake prediction in terms of Load-Unload Response Ratio(LURR)(Yin 1987, Yin 2006). In the present paper, we introduces the basic scientific problems, including how to load and unload the crust block, how to select proper geophysical parameters as response, and how to define LURR. Based on experiments, numerical simulations and damage mechanics analysis, the universal feature of LURR evolution before a strong earthquake has been revealed. More precisely, LURR fluctuates around 1 at the initial stage of preparation process, and then climbs to an anomalously high value(peak-point). Earthquake does not occur at this time. Instead, there is a delay time duration denoted as T2, which is related to the magnitude of the event. In order to predict earthquake in China,we propose to conduct countrywide spatial-temporal scanning of LURR, then to integrate with dimensional analysis so as to include more geophysical conditions into consideration. In this way, we have drawn up an approach to predict comprehensively the location, magnitude and occurrence time of forthcoming strong earthquakes. Finally, the practice of earthquake prediction with LURR has been retrospected.更多还原