2017年8月8日四川阿坝州九寨沟县发生M 7.0地震，随后发生一系列余震。该地震发生在川甘交界处四川一侧。国内外科研机构对主震的震源深度给出不同结果。本文采用PTD方法，采用四川省地震台网测定的震相数据，基于四川2015地壳速度模型，计算得到M 7.0主震震源深度为13 km，利用甘肃省地震台网震相数据，基于甘肃2015地壳速度模型，计算得到主震震源深度为12 km。震后流动台架设后，由近台证明PTD测定深度结果的可靠性。另外，计算M 3.0以上余震的震源深度。所有震相数据来自中国地震台网中心编目数据库。
An M 7.0 earthquake occurred on Aug. 8, 2017 in Jiuzhaigou County,Sichuan Province,which was followed by a series of aftershocks. The earthquake struck on the Sichuan side of the Sichuan-Gansu provincial boundary. Domestic and foreign scientific research institutions have obtained different results for the focal depth of the main shock. In this paper, PTD method is used to determine the focal depth. The result is 13 km by using data of Sichuan Seismic Network and Sichuan 2015 velocity model. Meanwhile, another result for the hypocenter depth is 12 km by using data of Gansu Seismic Network and Gansu 2015 velocity model. The reliability of the PTD results is proved by the close station after the installation of the mobile seismic station. In addition, the focal depths of aftershocks above M 3.0 are also calculated. All the seismic phase data is from the catalog database of China Earthquake Networks Center.
2017,38(4): 15-20 收稿日期：2017-08-20
DOI：10.3969/j.issn.1003-3246.2017.04.003
基金项目：上海市地震局科技专项（项目编号：2017专2）；中国地震局监测司专项（项目编号：17110402）
作者简介：宋秀青(1974-),女,工程师,主要从事地震监测、数字地震资料应用、速度模型研究等工作。E-mail:dzzysdyj@126.com
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