A Renormalization Group Model for Observed Temporal Fluctuations in Regional Seismicity

9508040 SAMMIS本研究是为了测试导致地震破坏过程的理论，其中幂律时间到破坏方程可以从重整化群理论中导出，其中主震被视为一个临界点。有证据表明，地震准备过程涉及一个空间扩展的区域断层网的集体行为。例如，在许多大地震之前，在主震周围的大片区域内，中等规模地震的数量会增加。重整化群论处理的优点是，可以推导出尺度的一阶校正，它采用失效时间对数的周期函数的形式，并调制了事件前地震活动性的幂律增加。这种对数周期校正在1989年洛马普里塔地震前的区域地震活动资料中表现得很明显。该分析将继续使用洛马·普里塔的数据，并扩展到加州其他地点和阿留申群岛。这项研究是国家减少地震危害计划的一个组成部分。＊＊＊

9508040 SAMMIS This research is to test a theory of the process leading to earthquake failure in which a power law time-to-failure equation can be derived from renormalization group theory where the mainshock is viewed as a critical point. There is some evidence that the earthquake preparation process involves the collective behavior of a spatially extended regional fault network. For example, many large earthquakes are preceded by an increase in the number of intermediate sized events within a large region surrounding the main shock. The advantage of the renormalization group theory treatment is that the first order correction to scaling can be derived which takes the form of a periodic function of the logarithm of the time to failure, and which modulates a power law increase in pre-event seismicity. This log-periodic correction is evident in the regional seismicity data which preceded the 1989 Loma Prieta earthquake. The analysis will continue with the Loma Prieta data and be extended to other California sites and the Aleutian Islands. This research is a component of the National Earthquake Hazard Reduction Program. ***