Receiver functions of CCDSN and crustal structure of Chinese mainland
Xuzhang Shen1, Huilan Zhou2
1 Lanzhou Institute of Seismology, China Earthquake Administration, Lanzhou 730000, China 2 Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, Beijing 100049, China
Receiver functions of CCDSN and crustal structure of Chinese mainland
Xuzhang Shen1, Huilan Zhou2
1 Lanzhou Institute of Seismology, China Earthquake Administration, Lanzhou 730000, China 2 Laboratory of Computational Geodynamics, Graduate University of Chinese Academy of Sciences, Beijing 100049, China
摘要The teleseismic receiver functions of 48 stations belonging to the CCDSN are used to invert the crustal structure beneath each station with the neighborhood algorithm. Thin layers with low velocity have been found beneath eight stations with “abnormal” observed receiver functions. Unreasonable results of few stations have been adjusted lightly with the trial-and-error method. The final result indicates that the crust in the western China is relatively thicker than the eastern China. The crust thickness beneath the Tibetan plateau is very large, which reaches 84 km at the station LSA. Double-crust structure exists below the stations LSA and CAD in Tibet, which might imply the collision between the Indian and Eurasian plates. A pronounced low velocity zone in the lower crust beneath the station TNC of Yunnan province might relate to the high temperature or emergence of partially molten material caused by Quaternary volcano, magma and geothermal activities in this area. The Moho is a transitional zone made up of thin layers instead of simple sharp discontinuity beneath several stations. The Conrad discontinuity is clearly identified beneath 20 stations mainly in the southeastern China, whereas it is blurry beneath 14 stations and uncertain beneath remaining stations.
Abstract：The teleseismic receiver functions of 48 stations belonging to the CCDSN are used to invert the crustal structure beneath each station with the neighborhood algorithm. Thin layers with low velocity have been found beneath eight stations with “abnormal” observed receiver functions. Unreasonable results of few stations have been adjusted lightly with the trial-and-error method. The final result indicates that the crust in the western China is relatively thicker than the eastern China. The crust thickness beneath the Tibetan plateau is very large, which reaches 84 km at the station LSA. Double-crust structure exists below the stations LSA and CAD in Tibet, which might imply the collision between the Indian and Eurasian plates. A pronounced low velocity zone in the lower crust beneath the station TNC of Yunnan province might relate to the high temperature or emergence of partially molten material caused by Quaternary volcano, magma and geothermal activities in this area. The Moho is a transitional zone made up of thin layers instead of simple sharp discontinuity beneath several stations. The Conrad discontinuity is clearly identified beneath 20 stations mainly in the southeastern China, whereas it is blurry beneath 14 stations and uncertain beneath remaining stations.
基金资助:the basic research and development fund from Institute of Earthquake Science, China Earthquake Administration (grant No. 2011IESLZ05) and the National Natural Science Foundation of China (grant Nos. 40374009 and 40904014)
通讯作者:
Xuzhang Shen
E-mail: shenxzh@gmail.com
引用本文:
Xuzhang Shen, Huilan Zhou. Receiver functions of CCDSN and crustal structure of Chinese mainland[J]. 《地震学报》英文版, 2012, 25(1): 3-16.
Xuzhang Shen, Huilan Zhou. Receiver functions of CCDSN and crustal structure of Chinese mainland. Earthquake Science, 2012, 25(1): 3-16.
