论文部分内容阅读
本文据Bruce A.Bolt等提出的方法,处理了辽宁省抚顺地震台记录的39个海城余震共66张记录图,以及沈阳地震台记录的16个海城余震共32张记录,得到地震矩与地震图上记录的S波的最大振幅,震波持续时间和震中距三要素的乘积的对数关系表达式为: LogM_o=(15.24± 0.79)+(0.75± 0.15)Log(C×D×Δ~p)(1) LogM_o=(15,88±1.09)+(0.58±0.20)Log(C×D×Δ~p)(2)并利用(1)式求得辽宁省鞍山台记录的59个海城余震(1977—1978年,M_s2.0-3.2)的地震矩,得到地震矩M′o与M_s的关系表示为; LogM′o=16.8+0.7M_s (3)结果表明,用该方法测定地震矩,结果稳定。 本文同时还对其中42个海城余震的初动半周期和初动振幅进行了测量并求出这些地震的震源参数,对二种方法得到的结果进行了比较。 应力降的测定结果表明1977—1978年4月海城余震的应力降似乎高于1975年2—5月余震的应力降。
According to the method proposed by Bruce A. Bolt et al., A total of 66 records of 39 Haicheng aftershocks recorded by the Fushun Seismic Station in Liaoning Province and 32 Haicheng aftershocks recorded by the Seismological Station of Shenyang were processed. The seismic moment The logarithmic relationship between the maximum amplitude of S-wave, the duration of the shock wave and the epicentral distance recorded from the seismogram is: LogM_o = (15.24 ± 0.79) + (0.75 ± 0.15) Log (C × D × Δ ~ (1) LogM_o = (15,88 ± 1.09) + (0.58 ± 0.20) Log (C × D × Δ ~ p) (2) The relationship between the seismic moment M’o and M_s is shown as follows: LogM’o = 16.8 + 0.7M_s (3) The results show that using this method to measure the seismic moment of aftershock in Haicheng (M_s2.0-3.2 from 1977 to 1978) Earthquake moment, the result is stable. In the meantime, the initial half-cycles and initial amplitudes of the 42 Haicheng aftershocks were also measured and the source parameters of these earthquakes were obtained. The results of the two methods were compared. The results of the stress drop show that the stress drop of Haicheng aftershocks in April 1977-1978 appears to be higher than the stress drop of aftershocks in February-May 1975.