TY - JOUR
T1 - P-wave tomography and origin of the Changbai intraplate volcano in Northeast Asia
AU - Lei, Jianshe
AU - Zhao, Dapeng
N1 - Funding Information:
We used the waveform data recorded by a portable seismic network installed by a research team led by Prof. F. T. Wu. We thank the IRIS Data Management Center for providing the waveform data used in this study. R. Engdahl provided the hypocentral parameters of the teleseismic events he relocated. M. Sambridge and X. Li provided the data for the geometry of the subducting Pacific slab in the present study area. The GMT software package distributed by Wessel and Smith (1995) was used for plotting the figures. This work is partially supported by grants from the Japan Society for the Promotion of Science (No. 11440134, No. 12002006). We thank Profs. E. Takahashi, T. Irifune, A. Yamada and M. Zhang for helpful discussions. We also thank the editors and two anonymous reviewers for their constructive comments and suggestions.
PY - 2005/3/16
Y1 - 2005/3/16
N2 - We present the first seismic image of the upper mantle beneath the active intraplate Changbai volcano in Northeast Asia determined by teleseismic travel time tomography. The data are measured at a new seismic network consisting of 19 portable stations and 3 permanent stations. Our results show a columnar low-velocity anomaly extending to 400-km depth with a P-wave velocity reduction of up to 3%. High velocity anomalies are visible in the mantle transition zone, and deep-focus earthquakes occur at depths of 500-600 km under the region, suggesting that the subducting Pacific slab is stagnant in the transition zone, as imaged clearly by global tomography. These results suggest that the intraplate Changbai volcano is not a hotspot like Hawaii but a kind of back-arc volcano related to the deep subduction and stagnancy of the Pacific slab under Northeast Asia.
AB - We present the first seismic image of the upper mantle beneath the active intraplate Changbai volcano in Northeast Asia determined by teleseismic travel time tomography. The data are measured at a new seismic network consisting of 19 portable stations and 3 permanent stations. Our results show a columnar low-velocity anomaly extending to 400-km depth with a P-wave velocity reduction of up to 3%. High velocity anomalies are visible in the mantle transition zone, and deep-focus earthquakes occur at depths of 500-600 km under the region, suggesting that the subducting Pacific slab is stagnant in the transition zone, as imaged clearly by global tomography. These results suggest that the intraplate Changbai volcano is not a hotspot like Hawaii but a kind of back-arc volcano related to the deep subduction and stagnancy of the Pacific slab under Northeast Asia.
KW - Changbai volcano
KW - Intraplate volcanism
KW - Subducted Pacific slab
KW - Teleseismic travel time tomography
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U2 - 10.1016/j.tecto.2004.12.009
DO - 10.1016/j.tecto.2004.12.009
M3 - Article
AN - SCOPUS:14644425996
SN - 0040-1951
VL - 397
SP - 281
EP - 295
JO - Tectonophysics
JF - Tectonophysics
IS - 3-4
ER -