Frequency-dependent Layered Q Model and Attenuation Tomography of the Himachal North-West Himalaya, India: Insight to Explore Crustal Variation

IF 1.9 4区地球科学 Q2 GEOCHEMISTRY & GEOPHYSICS pure and applied geophysics Pub Date : 2024-11-28 DOI:10.1007/s00024-024-03618-6

Parveen Kumar, V. J. Sahakian, Monika, Sandeep

{"title":"Frequency-dependent Layered Q Model and Attenuation Tomography of the Himachal North-West Himalaya, India: Insight to Explore Crustal Variation","authors":"Parveen Kumar, V. J. Sahakian,  Monika,  Sandeep","doi":"10.1007/s00024-024-03618-6","DOIUrl":null,"url":null,"abstract":"<div>The three-dimensional attenuation structure and frequency-dependent attenuation layered model are proposed for constraining seismic hazards and exploring the presence of an intra-crustal high conductive (ICHC) layer in the Himachal Himalaya, India. Using acceleration data recorded in the Himachal Himalaya, this work quantifies the attenuation characteristics in the form of shear-wave quality factor (Qβ). The low Qβ values (ranging 10–60) depict an aqueous fluid zone starting from a depth of ~ 11 km. This aqueous fluid identified in the study region closely resembles the ICHC layer identified by other researchers in its adjacent area. The geometry of the Main Himalayan Thrust (MHT) is explored in terms of the obtained attenuation model, which suggests the absence of a ramp structure of MHT below the Main Central Thrust (MCT) in the study region. The presence of an aqueous fluid zone identified at 11–20 km depth may be one of the possible reasons for high seismicity in the Himalayan seismic belt. This work also suggests a frequency-dependent shear wave attenuation (Qβ(f)) model of the form Qof n for six different layers of 5 km thickness each. The obtained layered model suggests low Q values, i.e., (49 ± 16) f (0.60±0.12) for layer 3 (10–15 km) and (27 ± 11) f (0.99±0.18) for layer 4 (15–20 km), corresponding to the aqueous fluid in the study region. The obtained Qβ(f) model appraises the region’s seismic hazard by describing the heterogeneity and tectonic activity level in the present study region.</div>","PeriodicalId":21078,"journal":{"name":"pure and applied geophysics","volume":"181 12","pages":"3539 - 3559"},"PeriodicalIF":1.9000,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"pure and applied geophysics","FirstCategoryId":"89","ListUrlMain":"https://link.springer.com/article/10.1007/s00024-024-03618-6","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOCHEMISTRY & GEOPHYSICS","Score":null,"Total":0}

引用次数: 0

Abstract

The three-dimensional attenuation structure and frequency-dependent attenuation layered model are proposed for constraining seismic hazards and exploring the presence of an intra-crustal high conductive (ICHC) layer in the Himachal Himalaya, India. Using acceleration data recorded in the Himachal Himalaya, this work quantifies the attenuation characteristics in the form of shear-wave quality factor (Q_β). The low Q_β values (ranging 10–60) depict an aqueous fluid zone starting from a depth of ~ 11 km. This aqueous fluid identified in the study region closely resembles the ICHC layer identified by other researchers in its adjacent area. The geometry of the Main Himalayan Thrust (MHT) is explored in terms of the obtained attenuation model, which suggests the absence of a ramp structure of MHT below the Main Central Thrust (MCT) in the study region. The presence of an aqueous fluid zone identified at 11–20 km depth may be one of the possible reasons for high seismicity in the Himalayan seismic belt. This work also suggests a frequency-dependent shear wave attenuation (Q_β(f)) model of the form Q_of ⁿ for six different layers of 5 km thickness each. The obtained layered model suggests low Q values, i.e., (49 ± 16) f ^(0.60±0.12) for layer 3 (10–15 km) and (27 ± 11) f ^(0.99±0.18) for layer 4 (15–20 km), corresponding to the aqueous fluid in the study region. The obtained Q_β(f) model appraises the region’s seismic hazard by describing the heterogeneity and tectonic activity level in the present study region.

Abstract Image

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

喜马拉雅西北部喜马偕尔的频率相关层状Q模型和衰减层析成像：探索地壳变化的洞察

提出了印度喜马偕尔-喜马拉雅地区三维衰减结构和频率相关衰减层状模型，以抑制地震灾害和探索地壳内高导电性层的存在。利用喜马偕尔-喜马拉雅地区记录的加速度数据，以横波质量因子（Qβ）的形式量化了衰减特征。低Qβ值（范围在10-60之间）描述了一个从~ 11 km深度开始的含水流体带。在研究区域发现的这种含水流体与其他研究人员在其邻近区域发现的ICHC层非常相似。根据得到的衰减模型，探讨了喜马拉雅主逆冲构造的几何特征，表明研究区在中央主逆冲构造下方不存在喜马拉雅主逆冲斜坡构造。在11-20 km深度处发现的含水流体带的存在可能是喜马拉雅地震带地震活动性高的原因之一。这项工作还提出了一个形式为Qof n的频率相关剪切波衰减（Qβ(f)）模型，适用于6个不同的层，每层厚度为5公里。得到的层状模型显示，第三层（10-15 km）的Q值较低，为（49±16）f(0.60±0.12)，第四层（15-20 km）的Q值为（27±11）f(0.99±0.18)，与研究区含水流体相对应。得到的Qβ(f)模型通过描述研究区的非均质性和构造活动水平来评价该地区的地震危险性。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

pure and applied geophysics 地学-地球化学与地球物理

CiteScore

4.20

自引率

5.00%

发文量

240

审稿时长

9.8 months

期刊介绍： pure and applied geophysics (pageoph), a continuation of the journal "Geofisica pura e applicata", publishes original scientific contributions in the fields of solid Earth, atmospheric and oceanic sciences. Regular and special issues feature thought-provoking reports on active areas of current research and state-of-the-art surveys. Long running journal, founded in 1939 as Geofisica pura e applicata Publishes peer-reviewed original scientific contributions and state-of-the-art surveys in solid earth and atmospheric sciences Features thought-provoking reports on active areas of current research and is a major source for publications on tsunami research Coverage extends to research topics in oceanic sciences See Instructions for Authors on the right hand side.