Insight into the origin of the Tengchong intraplate volcano and seismotectonics in southwest China from local and teleseismic data
Insight into the origin of the Tengchong intraplate volcano and seismotectonics in southwest China from local and teleseismic data
复制标题
从局地和远震资料看西南地区腾冲板内火山成因及地震构造
DOI：
10.1029/2008jb005881
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发表时间：
2009-05
影响因子：
3.9
通讯作者：
Zhao, Dapeng
中科院分区：
文献类型：
--
作者：
Lei, Jianshe;Su, Youjin;Zhao, Dapeng
2008年6月18日收到；2009年2月22日修订；2009年3月10日接受；2009年5月13日发表。[1] 通过使用大量远震（数据）确定了中国西南云南省下地壳和上地幔的高分辨率层析成像。
Received 18 June 2008; revised 22 February 2009; accepted 10 March 2009; published 13 May 2009. [1] A high-resolution tomographic image of the crust and upper mantle under Yunnan Province in southwest China was determined by using a large number of teleseismic data measured precisely from digital seismograms as well as local- earthquake arrival times recorded by the dense Yunnan seismic network. The grid spacing of the tomographic model is 70 km 78 km in the horizontal directions and 4–70 km in depth. Our resulting model shows a clear low-velocity (low-V, <0.3% with respect to the average one-dimensional velocity model) column extending from the surface down to about 400-km depth under the active Tengchong volcano and some high-velocity (high-V) anomalies existing in the mantle transition zone. Furthermore, the low-Vanomaly extends horizontally toward the northeast at 250- to 400-km depth. Combining our tomographic results with geochemical and geological investigations, we infer that the Tengchong volcano is a rift-related volcano caused by the subduction and dehydration of the Indian plate as well as corner flow in the mantle wedge, though the subducted slab is a continental plate. Our results show that the upwelling flow under Tengchong originates at 400-km depth. A prominent low-V anomaly along the Red River fault zone extends down to the upper mantle (100-km depth), reflecting that the Red River fault zone may have cut through the crust to the upper mantle. The two Dayao earthquakes (M 6.1 and M 6.2) in 2003 occurred on the margin of high-V anomalies and are underlain by a prominent low-V anomaly in the lower crust and upper mantle, suggesting that the Dayao earthquakes may be associated with fluids released from the dehydration of the subducted Indian slab. These results are significantly improved compared with previous studies and provide new seismic constraints on the dynamic processes of the India-Asia collision.
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影响因子：
3
作者：
E. Engdahl;R. Hilst;R. Buland
通讯作者：
E. Engdahl;R. Hilst;R. Buland
影响因子：
2.9
作者：
R. Sibson
通讯作者：
R. Sibson
用远震接收函数绘制中国下方的上地幔不连续面
DOI：
10.1186/bf03352819
发表时间：
2008-08
期刊：
Earth, Planets and Space
影响因子：
--
作者：
通讯作者：
--
影响因子：
2.3
作者：
Dapeng Zhao;O. P. Mishra;R. Sanda
通讯作者：
Dapeng Zhao;O. P. Mishra;R. Sanda
影响因子：
--
作者：
Longwen Zhou;Jie Liu;Xiao-dong Zhang
通讯作者：
Longwen Zhou;Jie Liu;Xiao-dong Zhang