云南地区强震前的应变扰动异常

ANOMALY OF STRAIN DISTURBANCE BEFORE STRONG EARTHQUAKES IN YUNNAN REGION

摘要:

计算和分析了云南地区5次M_L ≥ 6.5强震前的应变扰动ε_i值.结果表明,地震前5~8年,归一化为4级的地震的ε_i出现明显的高值异常;未来震中区域ε_i值变小,周围地区增大,形成空区;ε_i值有由零星分布逐渐向震中区收缩、集中并增强的趋势.

Abstract:

Strain disturbance ε_i values before 5 strong earthquakes (M_L ≥ 6.5) in Yunnan region have been calculated and analyzed.The results indicate that about 5~8 years before earthquake ε_i values of earthquakes with magnitude of normalized 4 show obviously the abnormal high value;The ε_i values are lower in the coming epicenter,but increase in periphery of the epicenter,developing the gap;The ε_i values show a tendency from a random and scattered distribution to converging towards epicenter and strengthening.