甘肃地区一维速度模型计算研究  

Study on the One Dimensional Velocity Model in Gansu Area

作　　者：尹欣欣[1,2] 杨立明[1,2] 陈继锋[1,2] 王祖东 高永国[1,2] 

机构地区：[1]甘肃省地震局,甘肃兰州730000 [2]中国地震局兰州地震研究所,甘肃兰州730000

出　　处：《地震工程学报》2017年第1期154-159,共6页China Earthquake Engineering Journal

基　　金：中国地震局兰州地震研究所科技发展基金项目(2015Q02);中国地震局兰州地震研究所地震科技发展基金(2015ZB02)

摘　　要：采用2009年1月1日—2014年6月甘肃省境内所有地震的震相数据,分类拟合计算该地区一维速度模型,计算结果显示,利用少量震级较大地震数据来拟合的速度结果近似于用所有地震拟合结果。拟合得出新模型初步结果后,再从所有地震资料中选定台站包围好、震相标识规范的142个地震,利用Hyposat定位方法来计算莫霍面深度,参考其他模型的莫霍面深度,综合分析后在一定的扰动范围内通过Hyposat批处理程序进行迭代定位,对8 640次计算模型做残差对比,最终选取残差最小模型作为新模型,此模型除部分参数有较小的差别外与甘青模型基本一致。This paper aims to work out a one-dimensional velocity model for Gansu area with a large amount of seismic data gained by the digital measuring seismic technology. Specifically, this study does classification and fitting calculation to get a one-dimensional velocity model, using the data of seismic phase of all the earthquakes happened in Gansu province from the period between January, 2009 to June, 2016. The purpose of classification is to show the influence of the results of fitting calculation on the seismic data, and the results show that fitting of a few closely approximates of all the earthquakes. Because there are many recording stations for major earthquakes and their epicentral distances are well-distributed, major earthquakes are chosen to be the objects of the study. On the basis of the preliminary results of the new model through the fitting calculation, we relocated 142 earthquakes that azimuths are well-distributed and seismic phases are clear by Hyposat program to calculated the depth of Moho surface. We also refer- ence other models such as Ganqing Model,Crustl.0 and the averaging model of Gansu and the Accept- ance Function are applied as references. After this calculation, a Hyposat batch processing of iterative localization is done within the scope of disturbance gained from the comprehensive calculation. Finally, basedon the 8640 computations of the model and several residue contrasts, a model with minimum residue has been chosen as the new model. The newly-made model is basically consistent with the Ganqing Model, with just a few parameters different. The new model is applied to the location of 142 earthquakes, rela- tive to Ganqing model the average residual reduced 0.05. The model is a large range of average results that cannot be applied to all earthquakes. According to the selected 142 earthquake distribution location weight, the model is more suitable for the southeast region of Gansu. In order to test the availability of the model, the model will be used in the daily cataloging process

关 键 词：甘肃省 Hyposat定位 甘青走时表 一维速度模型 波速比 

分 类 号：P631[天文地球—地质矿产勘探]