泰国北部的最小一维速度模型

IF 1.6 4区 地球科学 Q3 GEOCHEMISTRY & GEOPHYSICS Journal of Seismology Pub Date : 2023-04-28 DOI:10.1007/s10950-023-10148-6
Kasemsak Saetang, Helmut Duerrast
{"title":"泰国北部的最小一维速度模型","authors":"Kasemsak Saetang,&nbsp;Helmut Duerrast","doi":"10.1007/s10950-023-10148-6","DOIUrl":null,"url":null,"abstract":"<div><p>Standard seismological practices use a 1-D velocity model to calculate and determine earthquake hypocenters. For Northern Thailand, a minimum 1-D velocity model with station delays by applying the VELEST code is first presented here, which can be applied for earthquake location determinations as well as an initial model for 3-D seismic tomography studies. Altogether 614 <i>P</i>- and 689 <i>S</i>-wave travel time data from 145 events were manually picked from earthquake waveforms recorded by 13 seismic stations operated under the Thai Meteorological Department (TMD) from October 2009 through March 2021. A set of five velocity models with 5-km-layer thicknesses down to 40 km depth were tested with earthquake locations to obtain the best-fit velocity models. Results provided minimum travel-time differences between observed and calculated <i>P</i> and <i>S</i> first arrival times. After 13–20 iterations, a reduction of RMS (root-mean-square) values of the travel time residuals approaching a final minimum was observed. The vertical distribution of the hypocenters indicates that seismicity is concentrated in the upper 20 km depth range below northern Thailand. Only few events are found at deeper levels. The 1-D velocity model has slightly lower velocity values than the global velocity model (ak135 and iasp91). Station delays of <i>P</i>- and <i>S</i>-waves are in the range of −0.8 s and +0.7 s, indicating laterally varying geology correlating with near-surface geology. Positive delay times are related to softer sedimentary rocks and sediments, and negative delay times to igneous rock outcrops.</p></div>","PeriodicalId":16994,"journal":{"name":"Journal of Seismology","volume":null,"pages":null},"PeriodicalIF":1.6000,"publicationDate":"2023-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10950-023-10148-6.pdf","citationCount":"0","resultStr":"{\"title\":\"A minimum 1-D velocity model of Northern Thailand\",\"authors\":\"Kasemsak Saetang,&nbsp;Helmut Duerrast\",\"doi\":\"10.1007/s10950-023-10148-6\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Standard seismological practices use a 1-D velocity model to calculate and determine earthquake hypocenters. For Northern Thailand, a minimum 1-D velocity model with station delays by applying the VELEST code is first presented here, which can be applied for earthquake location determinations as well as an initial model for 3-D seismic tomography studies. Altogether 614 <i>P</i>- and 689 <i>S</i>-wave travel time data from 145 events were manually picked from earthquake waveforms recorded by 13 seismic stations operated under the Thai Meteorological Department (TMD) from October 2009 through March 2021. A set of five velocity models with 5-km-layer thicknesses down to 40 km depth were tested with earthquake locations to obtain the best-fit velocity models. Results provided minimum travel-time differences between observed and calculated <i>P</i> and <i>S</i> first arrival times. After 13–20 iterations, a reduction of RMS (root-mean-square) values of the travel time residuals approaching a final minimum was observed. The vertical distribution of the hypocenters indicates that seismicity is concentrated in the upper 20 km depth range below northern Thailand. Only few events are found at deeper levels. The 1-D velocity model has slightly lower velocity values than the global velocity model (ak135 and iasp91). Station delays of <i>P</i>- and <i>S</i>-waves are in the range of −0.8 s and +0.7 s, indicating laterally varying geology correlating with near-surface geology. Positive delay times are related to softer sedimentary rocks and sediments, and negative delay times to igneous rock outcrops.</p></div>\",\"PeriodicalId\":16994,\"journal\":{\"name\":\"Journal of Seismology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.6000,\"publicationDate\":\"2023-04-28\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"https://link.springer.com/content/pdf/10.1007/s10950-023-10148-6.pdf\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Seismology\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://link.springer.com/article/10.1007/s10950-023-10148-6\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOCHEMISTRY & GEOPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Seismology","FirstCategoryId":"89","ListUrlMain":"https://link.springer.com/article/10.1007/s10950-023-10148-6","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}
引用次数: 0

摘要

标准的地震学实践使用一维速度模型来计算和确定震源。对于泰国北部,本文首次提出了通过应用VELEST代码获得的具有站点延迟的最小一维速度模型,该模型可用于地震位置确定,也可用于三维地震层析成像研究的初始模型。从2009年10月至2021年3月,泰国气象部门(TMD)运营的13个地震台站记录的地震波形中,人工挑选了145个事件的614个P波和689个s波走时数据。采用5 km层厚至40 km深度的5个速度模型与地震地点进行了测试,以获得最佳拟合速度模型。结果提供了观测和计算的P和S首次到达时间之间的最小旅行时间差异。经过13-20次迭代后,观察到旅行时间残差的均方根值(RMS)接近最终最小值。震源的垂直分布表明,地震活动集中在泰国北部以下20 km以上深度范围内。只有少数事件是在更深层次上发现的。一维速度模型的速度值略低于全局速度模型(ak135和iasp91)。纵波和横波台站延迟在- 0.8 s和+0.7 s范围内,表明与近地表地质相关的横向变化地质。正延迟时间与较软的沉积岩和沉积物有关,负延迟时间与火成岩露头有关。
本文章由计算机程序翻译,如有差异,请以英文原文为准。

摘要图片

查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
A minimum 1-D velocity model of Northern Thailand

Standard seismological practices use a 1-D velocity model to calculate and determine earthquake hypocenters. For Northern Thailand, a minimum 1-D velocity model with station delays by applying the VELEST code is first presented here, which can be applied for earthquake location determinations as well as an initial model for 3-D seismic tomography studies. Altogether 614 P- and 689 S-wave travel time data from 145 events were manually picked from earthquake waveforms recorded by 13 seismic stations operated under the Thai Meteorological Department (TMD) from October 2009 through March 2021. A set of five velocity models with 5-km-layer thicknesses down to 40 km depth were tested with earthquake locations to obtain the best-fit velocity models. Results provided minimum travel-time differences between observed and calculated P and S first arrival times. After 13–20 iterations, a reduction of RMS (root-mean-square) values of the travel time residuals approaching a final minimum was observed. The vertical distribution of the hypocenters indicates that seismicity is concentrated in the upper 20 km depth range below northern Thailand. Only few events are found at deeper levels. The 1-D velocity model has slightly lower velocity values than the global velocity model (ak135 and iasp91). Station delays of P- and S-waves are in the range of −0.8 s and +0.7 s, indicating laterally varying geology correlating with near-surface geology. Positive delay times are related to softer sedimentary rocks and sediments, and negative delay times to igneous rock outcrops.

求助全文
通过发布文献求助,成功后即可免费获取论文全文。 去求助
来源期刊
Journal of Seismology
Journal of Seismology 地学-地球化学与地球物理
CiteScore
3.30
自引率
6.20%
发文量
67
审稿时长
3 months
期刊介绍: Journal of Seismology is an international journal specialising in all observational and theoretical aspects related to earthquake occurrence. Research topics may cover: seismotectonics, seismicity, historical seismicity, seismic source physics, strong ground motion studies, seismic hazard or risk, engineering seismology, physics of fault systems, triggered and induced seismicity, mining seismology, volcano seismology, earthquake prediction, structural investigations ranging from local to regional and global studies with a particular focus on passive experiments.
期刊最新文献
Source parameters of the May 28, 2016, Mihoub earthquake (Mw 5.4, Algeria) deduced from Bayesian modelling of Sentinel-1 SAR data Fault imaging using earthquake sequences: a revised seismotectonic model for the Albstadt Shear Zone, Southwest Germany A logic-tree based probabilistic seismic hazard assessment for the central ionian islands of cephalonia and ithaca (Western Greece) Developing machine learning-based ground motion models to predict peak ground velocity in Turkiye Fault structures of the Haichenghe fault zone in Liaoning, China from high-precision location based on dense array observation
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1