{"title":"Ambient noise tomography reveals complex crustal structure beneath eastern and northeastern Tibet: Insight‐ into regional crustal flow","authors":"Tengfei Wu, Chenyang Zou, Yujin Hua, Meng Chen","doi":"10.1111/ter.12736","DOIUrl":null,"url":null,"abstract":"We present a 3‐D crustal S‐wave velocity (Vs) model for eastern and northeastern Tibet utilizing ambient noise tomography. Our model reveals that crustal flow channels are absent in northeastern Tibet. In this region, the Kunlun Fault (KLF) significantly impacts mid‐lower crust low‐Vs anomalies. In addition, isolated low‐Vs anomalies beneath the Qilian orogeny are unrelated to the low‐Vs materials of the Tibetan Plateau. In the mid‐lower crust of the Songpan‐Ganzi terrane, its northeastern corner exhibits continuous low‐Vs anomalies, limited to areas south of the West Qinglin and west of 104° E. This suggests that a small‐scale northward viscous flow of crustal materials exists in the eastern KLF. However, two significant crustal flow channels (<jats:italic>V</jats:italic>s ≤ 3.3 km/s) are observed in eastern Tibet. The east–west tectonic movements and the obstruction of the Sichuan Basin together facilitate the dispersion of crustal materials southward from eastern Tibet.","PeriodicalId":22260,"journal":{"name":"Terra Nova","volume":"146 1","pages":""},"PeriodicalIF":2.2000,"publicationDate":"2024-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Terra Nova","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1111/ter.12736","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
We present a 3‐D crustal S‐wave velocity (Vs) model for eastern and northeastern Tibet utilizing ambient noise tomography. Our model reveals that crustal flow channels are absent in northeastern Tibet. In this region, the Kunlun Fault (KLF) significantly impacts mid‐lower crust low‐Vs anomalies. In addition, isolated low‐Vs anomalies beneath the Qilian orogeny are unrelated to the low‐Vs materials of the Tibetan Plateau. In the mid‐lower crust of the Songpan‐Ganzi terrane, its northeastern corner exhibits continuous low‐Vs anomalies, limited to areas south of the West Qinglin and west of 104° E. This suggests that a small‐scale northward viscous flow of crustal materials exists in the eastern KLF. However, two significant crustal flow channels (Vs ≤ 3.3 km/s) are observed in eastern Tibet. The east–west tectonic movements and the obstruction of the Sichuan Basin together facilitate the dispersion of crustal materials southward from eastern Tibet.
我们利用环境噪声层析成像技术,提出了西藏东部和东北部的三维地壳 S 波速度(Vs)模型。我们的模型显示,西藏东北部没有地壳流动通道。在这一地区,昆仑断层(KLF)对中下部地壳低 Vs 异常有很大影响。此外,祁连造山带下的孤立低 Vs 异常与青藏高原的低 Vs 物质无关。在松潘-甘孜地块的中下地壳中,其东北角出现了连续的低Vs异常,仅限于西青林以南和东经104°以西地区。然而,在西藏东部观测到两条明显的地壳流动通道(Vs ≤ 3.3 km/s)。东西向构造运动和四川盆地的阻挡共同促进了地壳物质从西藏东部向南扩散。
期刊介绍:
Terra Nova publishes short, innovative and provocative papers of interest to a wide readership and covering the broadest spectrum of the Solid Earth and Planetary Sciences. Terra Nova encompasses geology, geophysics and geochemistry, and extends to the fluid envelopes (atmosphere, ocean, environment) whenever coupling with the Solid Earth is involved.