| 利用接收函数方法研究青藏高原东南部地壳结构 |
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| 引用本文： | 曹 旭,米 宁,于大勇,王良书,徐鸣洁,李 华,黄周传,王 攀.利用接收函数方法研究青藏高原东南部地壳结构[J].高校地质学报,2018,24(5):715. |
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| 作者姓名： | 曹 旭 米 宁 于大勇 王良书 徐鸣洁 李 华 黄周传 王 攀 |
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| 摘 要： | 青藏高原东南部作为板块碰撞的前缘地带一直是地球科学研究的热点，为了揭示碰撞前缘地带地壳结构特征，作者
利用布设在中国青藏高原东南部的38个宽频带流动台站记录的2487条远震P波接收函数，采用接收函数CCP叠加（共转换点
叠加）和H-κ叠加两种方法获得了研究区域详细的地壳厚度图像和泊松比值。研究结果显示：两种方法获得的地壳厚度特征
具有较好的一致性；青藏高原东南部地壳厚度存在明显的东西差异和南北差异；喜马拉雅构造区内莫霍面深度变化较大，
介于65~80 km之间；拉萨地体内莫霍面深度介于72~80 km之间；雅鲁藏布缝合带两侧地壳厚度突变，缝合带北侧和南侧地
壳厚度相差约8 km。研究区域平均泊松比值较小，为0.24，和大多数造山带泊松比偏低的特征类似。研究区域中下地壳广
泛存在强转换界面，该界面可能对应中下地壳高速层的上界面，埋深40~70 km，表明壳内发生深熔或部分熔融作用，导致
壳内发生重力分异，在中下地壳形成了高速薄层。
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| 关 键 词： | 青藏高原东南部 接收函数 H-κ叠加 CCP叠加 地壳结构 |
Crustal Structure of SE Tibet Plateau by Receiver Function |
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| CAO Xu,MI Ning,YU Dayong,WANG Liangshu,XU Mingjie,LI Hua,HUANG Zhouchuan,WANG Pan.Crustal Structure of SE Tibet Plateau by Receiver Function[J].Geological Journal of China Universities,2018,24(5):715. |
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| Authors: | CAO Xu MI Ning YU Dayong WANG Liangshu XU Mingjie LI Hua HUANG Zhouchuan WANG Pan |
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| Abstract: | As the front region of plate collision, the southern Tibet has always been the hotspot in geoscience research. To
reveal the features of the crustal structure of collision frontal zone, we used 2487 tele-seismic records recorded by 38 broadband
stations in the southeast Tibet. Then we calculated the crustal thickness and Poisson’s ratio of this area by CCP stacking and H-κ
stacking. The results of the crustal thickness obtained by the two methods are in good agreement, and the crustal thickness in the
southeastern Tibet has obvious difference in east-west and north-south. The depth of Moho varies greatly in the Himalaya tectonic
zone, ranging from 65 to 80 km. The depth of Moho in Lhasa block ranges from 72 km to 80 km. The crustal thickness on both
sides of the Yarlung Zangbo suture has been abruptly changed. The difference in thickness between the north side and the south
side of the suture is about 8 km. The average Poisson ratio in the study area is 0.24, which is consistent with the feather that the
Poisson ratio in most orogenic belts is low. A strong transition interface exists widely in the middle and lower crust of the study
area, the interface may be the upper interface of the high-velocity layer in the middle-lower crust, with a depth of 40-70 km. It
indicated that deep melting or partial melting occurred in the crust, leading to gravitational differentiation and forming a highvelocity
thin layer in the middle-lower crust. |
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| Keywords: | southeastern Tibet receiver function H-κstacking CCP stacking crustal structure |
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