2013年巴基斯坦Mw7.7地震震源参数特征及烈度分布估计

地震 ›› 2014, Vol. 34 ›› Issue (4): 12-19.

2013年巴基斯坦M_w7.7地震震源参数特征及烈度分布估计

孟令媛, 周龙泉, 刘杰

中国地震台网中心,北京100045

收稿日期:2014-03-20 修回日期:2014-05-05 发布日期:2020-09-11
作者简介:孟令媛(1983-),女,河北唐山人,助理研究员,主要从事震源物理、强地面运动预测模型等研究。
基金资助:
国家科技支撑计划项目(2012BAK19B02-01)、中国地震局监测预报司震情跟踪合同制定向工作任务(2014020412)及中国地震台网中心青年科技基金(QNJJPZ- YBB- 1307)联合资助

Source Parameters and Estimation of Intensity Distribut ion for the 2013 M_w7.7 Pakistan Earthquake

MENG Ling-yuan, ZHOU Long-quan, LIU Jie

China Earthquake Net works Center, Beijing 100045, China

Received:2014-03-20 Revised:2014-05-05 Published:2020-09-11

摘要/Abstract

摘要： 2013年9月24日巴基斯坦中南部发生M_w7.7地震,震中位于巴基斯坦阿瓦兰县北部69 km处,发震断层为走滑断层机制,极震区烈度达到IX度以上。我们计算了巴基斯坦地震的视应力、应力降等震源参数,明确该地震为断层动态摩擦过程中的应力上调模式;进一步选取发震断层面上滑动位移的反演结果,构建有限断层模型,对近断层区域的强地面运动进行估算,并基于强地面运动模拟结果给出震区的烈度分布图。结果显示,模拟的巴基斯坦地震烈度图极震区烈度达到IX度,VII度烈度影响范围与美国地质调查局震后给出的震动图(ShakeMap)较为一致。强烈地震发生后,基于强地面运动模拟计算给出的烈度分布情况具备较好的合理性,对震区给出及时的震情判定和开展相应的救灾工作具有较高的实际价值。

关键词: 巴基斯坦M_w7.7地震, 视应力, 有限断层模型, 模拟烈度分布

Abstract: The 24 September, 2013 M_w7.7 earthquake occurred in south-central Pakistan as the result of strike-slip at the shallow crustal depth of 25 km. This event occurred within the transition zone between nor thward subduction of the Arabia plate beneath the Eurasia plate and northward colision of the India plate with the Eurasia plate. The location of Pakistan earthquake is 69 km to north of Awaran, Pakistan. The maximum intensity is upto IX in the near-fault field shown in the ShakeMap of the USGS. In this study, we analyze the dyna mic source process with the source mechanism, select the effect of slip distribution on the fault plane based on two models. One finite fault source model is constructed and we calculate the strong ground motion including acceleration and velocity. Based on the simulated results of the near-fault strong ground motion, we describe the intensity distribution of the Pakistan eart hquake. The simulated intensity indicates that the maximum intensity value is IX and region with and above VI is consistence with the ShakeMap of USGS. In fact, numerical modeling developed in this study has great application in the strong ground motion prediction and intensity estimation for earthquake rescue purpose.

Key words: Finite fault source model, Simulated intensity distribution, A pparent stress, Pakistan Mw7. 7 earthquake

中图分类号:

P315.7

孟令媛, 周龙泉, 刘杰. 2013年巴基斯坦M_w7.7地震震源参数特征及烈度分布估计[J]. 地震, 2014, 34(4): 12-19.

MENG Ling-yuan, ZHOU Long-quan, LIU Jie. Source Parameters and Estimation of Intensity Distribut ion for the 2013 M_w7.7 Pakistan Earthquake[J]. EARTHQUAKE, 2014, 34(4): 12-19.

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