摘要
本文借鉴直接拟合烈度数据点和枚举震源参数的做法,设计了一种利用烈度资料估计6级左右历史地震震源参数的方法.该方法对震源参数所有可能的组合进行枚举,采用地震波场模拟计算转换的理论烈度值,利用模型选择方法评估各可能的震源参数组合模型与历史破坏记录推断的地震烈度数据点的拟合程度,对震源参数做出估计.该方法充分考虑到历史资料相对稀少对震源参数估计的影响,以多种震源参数估计结果和相应权重值来定量化表示估计的不确定性.通过对给定震中位置、震源深度和滑动角的Bootstrap数值恢复检测与2006年美国Parkfield 6.0级地震实例的测试,表明该方法得出的震源参数估计结果具有统计一致性和一定的无偏性.将该方法应用于1882年河北深县6级地震的震源参数估计,结果显示东西向旧城北断层或何庄断层及北东东走向的深西断层为深县地震的发震构造的可能性较大.
We herein describe a new approach to quantitatively estimate source parameters of historical earthquakes with magnitude - 6 using macroseismic data and synthetic seismograms. This approach enumerates all possible models with different source parameters （such as epicenter location, focal depth and rake）, and obtains theoretic intensity distribution of each model from synthetic waveform modeling, then evaluate source models fitting degree for intensity data inferred from historical earthquake records to determine its parameters. We use multiple model solutions and model weights to give quantitatively the uncertainty of source parameters caused by relatively scarce historical information. This approach was tested with Bootstrap numerical cases for given sources with random deviations, and the well determined source parameters of the 2004Parkfield M6.0 earthquake. The test showed that the result is robust statistically. Finally the approach is applied to the 1882 Shenxian M~ 6 earthquake occurred in Hebei province, China. Source parameters estimation results show that the Shenxian earthquake is caused possibly by Jiuchengbei fault or Hezhuang fault, or Shenxi fault.
出处
《地球物理学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第8期2701-2717,共17页
Chinese Journal of Geophysics
基金
国家自然科学基金项目(41074038)资助
关键词
历史地震
震源参数
烈度资料
地震波场模拟
模型选择
Historical earthquake, Source parameters, Intensity data, Synthetic waveformmodeling, Model selection
