Undulating Moho beneath a near-uniform surface of central Tibet
Undulating Moho beneath a near-uniform surface of central Tibet
复制标题
西藏中部近乎均匀的地表下起伏的莫霍面
DOI：
10.1016/j.epsl.2020.116343
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发表时间：
2020-08
影响因子：
5.3
通讯作者：
Yang Jiang
中科院分区：
文献类型：
--
作者：
Wang-Ping Chen;Yang Jiang
我们提出了805个可靠的地壳厚度估计在西藏中部，揭示了起伏的莫霍面下的一个几乎均匀的表面最高和最大的高原在世界上。我们的结果来自于地震仪附近虚拟震源（虚拟深地震测深，VDSS）的P波广角反射。虚拟震源是由大震在后方位上均匀分布产生的，我们还利用观测到时随射线参数的明显变化来独立约束地壳的体厚度和P波速度（约6.3km/s），因此两个参数之间没有太大的折衷。此外，我们认为在上地幔已知的非均质性的影响。在Hi-CLIMB线性阵列周围的区域，除了先前提出的向北趋势外，还有向东的地壳减薄趋势。这些趋势分别是近似平行和正常的印度地幔前（IMF），或北方，印度的俯冲岩石圈地幔的前缘，从收集的额外的地球物理证据推断。IMF附近的莫霍面也显示出较大的三维深度变化，促使我们提出，完整的印度下地壳的前缘，或印度地壳前缘（ICF），伴随着下冲的印度岩石圈地幔下藏，位于沿着莫霍面扰动带。根据中国国家地震台网十多个永久性宽频带地震仪的结果，ICF以南的印度洋莫霍面大致平坦，因此可能是稳定的，它显然向东延伸了500 km，约为93°E。
We present 805 reliable estimates of crustal thickness in central Tibet, revealing an undulating Moho beneath a near-uniform surface of the highest and the largest plateau in the world. Our results are derived from wide-angle reflections ofP-waves from virtual seismic sources near seismographs (Virtual Deep Seismic Sounding, VDSS). The virtual sources are produced by large earthquakes well-distributed in back-azimuth; and we also utilize obvious changes of measured arrival times as a function of ray-parameter to constrain independently bulk thickness andP-wave speed of the crust (about 6.3 km/s), so there is little trade-off between the two parameters. Additionally, we consider effects of known heterogeneities in the upper mantle. In regions surrounding theHi-CLIMBlinear array, there is an eastward trend, in addition to the previously proposed northward trend, of crustal thinning. Respectively, these trends are approximately parallel and normal to the Indian mantle front (IMF), or the northern, leading edge of underthrust lithospheric mantle of India, deduced from a collection of additional geophysical evidence. The Moho near the IMF also shows large, 3-D variations in depths, prompting us to propose that the leading edge of intact Indian lower crust, or the Indian crustal front (ICF) that accompanied the underthrusting Indian lithospheric mantle beneath Tibet, lies along the zone of disturbed Moho. Based on results from about a dozen permanent broadband seismographs of the China National Seismic Network, more-or-less flat-lying, and thus presumably stable, cratonic Indian Moho south of the ICF apparently extends eastward for another 500 km to about 93°E.
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接收函数图像揭示藏西地区俯冲印度岩石圈的详细结构
影响因子：
3.9
作者：
Xu Qiang;Zhao Junmeng;Yuan Xiaohui;Liu Hongbing;Pei Shunping
通讯作者：
Pei Shunping
DOI：
10.1002/2016jb013046
发表时间：
2016-08
期刊：
Journal of Geophysical Research: Solid Earth
影响因子：
--
作者：
Chunquan Yu;Wang-Ping Chen;R. Hilst
通讯作者：
Chunquan Yu;Wang-Ping Chen;R. Hilst
影响因子：
2.9
作者：
Wang-Ping Chen;Chunquan Yu;T. Tseng;Zhaohui Yang;Chi‐yuen Wang;J. Ning;T. Leonard
通讯作者：
Wang-Ping Chen;Chunquan Yu;T. Tseng;Zhaohui Yang;Chi‐yuen Wang;J. Ning;T. Leonard
使用虚拟深地震探测同时测定大块地壳特性
影响因子：
3
作者：
Qing Chen;Wang-Ping Chen
通讯作者：
Wang-Ping Chen
影响因子：
2.8
作者：
KENNETT, BLN;ENGDAHL, ER
通讯作者：
ENGDAHL, ER