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从全球数字地震台网的长周期记录中,选择了震中距小于90°的27个台站的54个P波震相和44个S波震相资料.首先,用波形反演方法确定了2001年1月26日印度古杰拉特（Gujarat）Ms7.8地震的地震矩张量、震源机制、震源时间函数和时空破裂过程等震源参数.通过矩张量反演,并根据Kutch Mainland断层的走向、地震烈度的空间分布、余震震源的空间分布和震害的空间分布,确认2001年1月26日印度古杰拉特Ms7.8地震的发震断层的走向为92°、倾角为58°、滑动角为62°,即一走向近东-西向、断层面向南倾斜、以逆冲为主的左旋-逆断层.这次地震所释放的地震矩为3.5X1020N·m,矩震级Mw=7.6.然后,借助合成地震图,采用频率域求谱商的方法,得到了依赖于台站方位的27个P波震源时间函数、22个S波震源时间函数以及平均的P波震源时间函数和S波震源时间函数.对震源时间函数的分析表明,这次地震是一次连续的破裂事件,开始比较急途,但结束比较迟缓,总持续时间约19s.最后,以所提取的P波和S波震源时间函数为资料,采用时间域的反演技术得到了断层面上滑动的时空分布.滑动量在断层面上的静态分布表明,断层面上的最大滑动量约为7m.断层面上的最大应力降约为30MPa,平均应力降约为7MPa.滑动量大于0.5m的区域在走向方向长85km,在断层面倾斜方向宽?
From the long-period records of the global digital seismograph network, 54 P-wave facies and 44 S-wave facies data were selected from 27 stations with epicentral distance less than 90 ° .Firstly, waveform inversion method was used to determine the 2001 Earthquake moment tensor, focal mechanism, source time function and time-space rupture process of the Gujarat MS7.8 earthquake on January 26, 2006. By using the moment tensor inversion and according to the Kutch Earth fault Direction, the spatial distribution of seismic intensity, the spatial distribution of aftershocks and the spatial distribution of earthquakes. It was confirmed that the strike-fault faulting direction of the Gujarat MS7.8 earthquake on January 26, 2001 was 92 ° and the dip angle was 58 ° With a sliding angle of 62 °, ie, a strike-to-east-west direction fault with a southward thrust fault and a thrust-dominated L-reverse fault.The seismic moment released by this earthquake is 3.5X1020N · m and moment magnitude Mw = 7.6. Then, by means of synthetic seismogram and frequency spectrum quotient, we obtain 27 P wave source time functions, 22 S wave source time functions and average P wave source time functions and S wave Source time functions. An analysis of source time functions shows that this earthquake It is a continuous rupture event, which starts to be more urgent, but ends relatively slowly, with a total duration of about 19s. Finally, using the extracted P-wave and S-wave source time functions as the data, the fault plane The spatial and temporal distribution of slip on the fault plane shows that the maximum slip on the fault plane is about 7m.The maximum stress drop on the fault plane is about 30MPa and the average stress drop about 7MPa.The slip is greater than 0.5 The area of m is 85km long in the strike direction and wide in the diagonal direction of the fault plane