CAJ | 학술논문

运用经验格林函数法模拟2013年4月20日芦山 MS 7．0地震的近场强地面运动．在拟合过程中，首先参考前人远场反演结果给出的滑动量分布特征和主震波形的包络线特征，确定强震动生成区的大致范围和数量；然后利用 Somerville 等提出的地震矩与凹凸体面积的经验关系式确定强震动生成区细小划分的初值，继而利用遗传优化算法确定以上二者的最优值及其它震源参数．将数值模拟波形与实际地震观测记录在时间域和频率域分别进行比较，结果显示，在所选取的30个观测台站中，多数台站的数值模拟结果与实际观测结果符合得很好，特别是大于1 Hz 的高频部分．断层面上有两个强震动生成区，其位置与前人反演的滑动量集中分布区相一致，而且强震动生成区规模比 Somerville 等获得的标度率估计值要小．
운용경험격림함수법모의2013년4월20일호산 MS 7．0지진적근장강지면운동．재의합과정중，수선삼고전인원장반연결과급출적활동량분포특정화주진파형적포락선특정，학정강진동생성구적대치범위화수량；연후이용 Somerville 등제출적지진구여요철체면적적경험관계식학정강진동생성구세소화분적초치，계이이용유전우화산법학정이상이자적최우치급기타진원삼수．장수치모의파형여실제지진관측기록재시간역화빈솔역분별진행비교，결과현시，재소선취적30개관측태참중，다수태참적수치모의결과여실제관측결과부합득흔호，특별시대우1 Hz 적고빈부분．단층면상유량개강진동생성구，기위치여전인반연적활동량집중분포구상일치，이차강진동생성구규모비 Somerville 등획득적표도솔고계치요소．
The near source strong ground motions of the 2013 MS 7.0 Lushan, China,earthquake were simulated using empirical Green’s function (EGF ) method.At first,we estimated the amount and location of strong motion gene-ration areas (SMGAs)based on the characteristics of both slip distributions from far-field seismic inversion and the envelopes of recorded acceleration from the main shock,and determined the amount of subfaults on SMGAs referring to the scaling law of asperity area versus seismic moment introduced by Somerville et al .Then,we implemented the genetic algorithm searching for the optimized value of above two and other source parameters.Based on the source models, we synthetized the waveforms for the 30 selected stations near the source region.The comparison of the synthetic waveforms with the observed recordsindicated that they agreed very well with each other,especially for the part ofhigh-frequency larger than 1 Hz.We found that there were two obvious SMGAson the fault,which take the position that the asperities from far-field seismicinversion take.The combined SMGAs we obtained were smaller than those predictedby extension of the scaling law by Somerville et al .