We present the first high‐resolution seismic images of the crust beneath the Arunachal Himalaya, using 22,525 high quality teleseismic receiver functions (RFs). Data from 32 broadband seismic stations deployed in the Arunachal Himalaya during 2010–2016 is used for this purpose. In addition, data from the HIMNT, SIKKIM, Hi‐CLIMB, and Geodynamics ANd Seismic Structure of the Eastern‐Himalaya Region networks are used to investigate along strike variations in the crustal architecture of the Eastern Himalayan mountain belt. Common Conversions Point stacks constructed using RFs from 203 seismic stations along various S‐N profiles reveal lateral variations in the crustal structure. We observe, (a) a less complex crust beneath the Arunachal Himalaya compared to that in the Nepal and Sikkim Himalaya (b) a highly deformed layer running parallel to the Main Himalayan Thrust (c) intermittent anisotropic low velocity layer in the middle crust (d) that the crustal thickness estimates are in close agreement with those in other segments of the Eastern Himalaya (40–60 kms) (e) no prominent signatures of a mid‐crustal ramp as observed in the Nepal Himalaya. The geometry of the crust in the Eastern Himalayan segments appears less complex compared to the Central Himalayan segments. The presence of strong anisotropy associated with the low velocity layer at depths of 20–30 km suggests a mechanically weak middle crust beneath Arunachal Himalaya. Attributing these anisotropic signatures to the channel flow model appears contentious.

中文翻译：

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阿鲁纳恰尔喜马拉雅山下地壳的地震成像

我们使用22,525个高质量的远震接收器功能（RF）展示了阿鲁纳恰尔喜马拉雅山下的地壳的第一个高分辨率地震图像。为此，使用了2010-2016年在阿鲁纳恰尔喜马拉雅山部署的32个宽带地震台站的数据。此外，还使用了来自喜马拉雅东部地区网络的HIMNT，SIKKIM，Hi-CLIMB和地球动力学和地震构造的数据来研究喜马拉雅东部山区地壳构造的走向变化。使用203个地震台站的RF沿不同的S-N剖面构造的通用转换点叠层揭示了地壳结构的横向变化。我们观察到 （a）与尼泊尔和锡金喜马拉雅山相比，阿鲁纳恰尔喜马拉雅山下面的地壳复杂程度较低（b）与喜马拉雅主推力平行延伸的高度变形层（c）中地壳的间歇性各向异性低速层（d）地壳厚度估算值与喜马拉雅东部其他地区（40-60公里）的估算值非常吻合（e）在尼泊尔喜马拉雅地区没有观察到明显的中地壳斜坡特征。与中部喜马拉雅山脉相比，东部喜马拉雅山脉中的地壳的几何形状看起来不那么复杂。与低速层有关的强各向异性存在于20–30 km的深度，这表明在Arunachal喜马拉雅山下方存在机械弱的中地壳。将这些各向异性特征归因于通道流模型似乎是有争议的。