区域矿震与地震的定量识别方法及其应用

The Mode Identification Method and Its Application to Regional Mine and Nature Earthquakes

选取Morlet小波作为基函数 ,提出了一种定量识别矿震和地震的时频能量衰减因子(α)的方法 ,研究了辽宁省抚顺和北镇台记录的矿震和地震的α值变化特征及其随震级的变化特点 ,得到了不同类型波的α值对震级的依赖关系。研究结果表明 :(1)一般情况下 ,同等震级水平的矿震与地震的α值具有明显差异 ,其变化范围相互不存在重叠现象 ;(2 )随震级增高 ,α值呈现下降特点且矿震α值随震级增高而下降的速率比地震大 ;(3)根据事件震级并结合α值与震级的统计关系 ,我们可以对已发生的事件类型作出正确判断 ;(4)区域矿震和地震破裂机制的差异是使α值具有明显差异的主要原因 ;(5 )同一地区的矿震或地震的α值具有稳定的变化规律 ,不同地区的α值变化规律有差异性。这对天然地震事件的快速定位和识别及基于固定台站研究强震前地震的α值的异常变化具有启发意义。

Based on the gauss linear frequency modulation wavelet transform,this paper puts forward a kind of new method which is called time-frequency energy attenuation factor (α value),studies the characteristics of α value and its rules along with earthquake magnitude from mine and nature earthquakes which are recorded by the Fushun and Beizhen digital stations which located at Liaoning Province, and gets the statistic relations between α value and specified earthquake magnitude. Studied results indicate that:(1)As a usual,α value of mine and nature earthquakes of same scale has obvious α difference and the variation range of α value is not superposition;(2)The α value decrease along with increasing of earthquake magnitude and decreasing ratio of mine earthquake is faster than nature earthquake;(3)Based on the event magnitude and combined the relation between α value and magnitude,we may judge the earthquake style;(4)The difference of earthquake focus between mine and nature earthquakes causes obvious difference of α value; and (5)To mine and nature earthquakes of same areas, α value variation is relatively steady. But to mine and nature earthquakes of different area,α value variation has obvious difference. Above-mentioned results have elicitation meaning to study the abnormal change of α value before strong earthquake.