地震深度定位对地壳速度结构模型有较大的依赖性。选取2017年安徽及周边ML 1.5以上地震,使用PTD与单纯型定位方法,分别配置华南模型与AH2015模型进行重新定位,研究不同模型对安徽地震深度的定位影响。研究表明,使用PTD方法,配置AH2015模型时定位深度略大,且符合安徽区域地震实际深度的记录台站较多;使用单纯型定位法,配置两种模型所得定位深度差距不大,且深度分布均匀。说明PTD方法定位地震深度对地壳速度结构模型的依赖程度较大,AH2015模型比华南模型更加符合安徽区域实际地壳结构。
Seismic depth positioning is very dependent on the crustal velocity model. In this article, PTD method and simplex positioning method are selected for the location of earthquakes above ML 1.5 that occurred in and around Anhui in 2017, configuring the South China model and the AH2015 model separately. Then the positioning depths are contrasted to research the influence of different models on the seismic depth of Anhui. The research shows that the positioning depth when configuring the AH2015 model by using the PTD method is slightly larger than those when configuring the South China model by using the PTD method, and moreover, the number of stations that meet the actual seismic depth in the Anhui region is more. The seismic depth of the two models is uniform by using the simplex positioning method, and there is not large difference between the two models. This shows that the PTD method to locate the seismic depth is more dependent on the crustal model than the simplex method, and the AH2015 model is more consistent with the actual Anhui regional crust structure than the South China model.
2019,40(1): 53-58 收稿日期:2018-4-12
DOI:10.3969/j.issn.1003-3246.2019.01.006
基金项目:中央引导地方专项资金科技惠民项目(项目编号:2018080802D117);安徽省地震科研基金(项目编号:20180420)
作者简介:谢石文(1989-),男,硕士研究生,安徽阜阳人,就职于安徽省地震局,主要从事地震定位算法研究工作。E-mail:ECITxshw@163.com
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