首都圈地区爆破、矿塌和天然地震的识别研究

Discrimination between explosions,mine collapses and earthquakes in capital region of China

选取首都圈地区2008年8月—2009年9月ML在2.0—2.2范围内的爆破、矿塌和天然地震数据资料,从时间域和频率域进行分析对比,总结出识别爆破、矿塌和天然地震的依据.在时域方面,爆破的初动方向向上,矿塌向下,天然地震的初动方向依赖于台站的分布情况;爆破和矿塌的面波比较发育;天然地震的S波与P波最大振幅比(AS/AP)大于爆破和矿塌,同时,爆破和矿塌的能量衰减比天然地震快.在频域方面,高频成分的能量衰减快于低频;天然地震的拐角频率较高,爆破次之,矿塌的最小;在震中距200km范围内,爆破的顶峰频率主要分布在5—7Hz,矿塌分布在2—4Hz,天然地震的顶峰频率较大,在10—18Hz范围内.另外,天然地震的频率域较宽,其次为爆破、矿塌.

Choosing seismic data of explosions, collapses and earthquakes with M1. in the range of 2.0-1-2.2 during August 2008 to September 2009 in capital region, and analyzing and comparing the data in time and frequency domain, this paper studies how to identify the explosion, mine collapse and earthquake. In time domain, vertical component first motion of explosion seismic records is upward, and that of mine collapses is downward, while that of earthquakes de pends on station distribution. The surface wave of explosion and mine collapse develops well. The S to P wave amplitude ratio （As/Ap） of earthquakes are lar ger than that of explosions and collapses. Moreover, energy attenuation of ex plosions and collapses is faster than that of earthquakes. In frequency domain the energy attenuation of high frequency wave is faster than that of low frequency one. For the events with similar magnitude, the corner frequencies of ampli-collapses are next-wide