理解前兆异常变化机理和地震短临前兆

本文概要介绍了国内外近几年在地壳形变一地球自转日长变化十年尺度相关性、静寂地震、前驱波三方面的重要研究发现，并分析了这三项研究发现在地震前兆异常机理认识中的作用。初步分析表明：深部核幔耦合作用引起的地壳形变、地球物理场十年尺度波动，是数年至十年尺度地震场兆波动性变化的重要调制因素之一；源于断层脆韧转换带(过渡层)的静寂地震一慢地震缓慢破裂过程，是数天至数月尺度地震短期异常变化产生的重要原因；源于脆韧转换层上部或弹脆性层薄弱部分慢地震过程所辐射出来的低频前驱波(慢地震波)，是目前已发现的可重复出现的短临前兆信号，具有数小时至7天左右的地震短临预报指标意义。

Understanding the Mechanisms of Premonitory Anamolies and Imminent Precursors

Three new scientific research finding and progress on decadal-scale correlation between crustal deformation and length of day, silent earthquake and precursory wave have been briefly introduced in this paper, and their implications to prem onitory anomaly and earthquake prediction are also analyzed. Tentative researche s demonstrate that: core-mantle coupling induced fluctuations in crustal deform ation, geophysical observations, are important modulations to back-ground anoma ly variations on years to decade-time scales; Slow rupture process within the t ransition zone of fault is an important source for short-term premonitory anoma lies on days to months time scales; The low-frequency precursory waves (slow ea rthquake waves) originating from transition zone or weaken brittle part of fault are repeatable and reliable imminent precursors, which generally come out sever al hours to seven days before strong earthquakes.