Abstract
Based on the inversion method of 2D velocity structure and interface, the crustal velocity structures of P-wave and S-wave along the profile L 1 are determined simultaneously with deep seismic sounding data in Changbaishan Tianchi volcanic region, and then its Poisson’s ratio is obtained. Calculated results show that this technique overcomes some defects of traditional forward calculation method, and it is also very effective to determine Poisson’s ratio distribution of deep seismic sounding profile, especially useful for study on volcanic magma and crustal fault zone. Study result indicates that there is an abnormally high Poisson’s ratio body that is about 30 km wide and 12 km high in the low velocity region under Tianchi crater. Its value of Poisson’s ratio is 8% higher than that of surrounding medium and it should be the magma chamber formed from melted rock with high temperature. There is a high Poisson’s ratio zone ranging from magma chamber to the top of crust, which may be the uprise passage of hot substance. The lower part with high Poisson’s ratio, which stretches downward to Moho, is possibly the extrusion way of hot substance from the uppermost mantle. The conclusions above are consistent with the study results of both tomographic determination of 3D crustal structure and magnetotelluric survey in this region.
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References
Cerveny V, Molotkov I A, Psencik I. 1977. Ray Method in Seismology [M]. Prague: University of Karlova, 79–86.
HU Jia-fu, SU You-jin, ZHU Xiong et al. 2003. S-wave velocity and Poisson’s ratio structure in Yunnan China and its significance [J]. Science in China (Series D), 33(8): 714–722.
LAI Xiao-ling, ZHANG Xiang-kang, YANG Jian. 1994. 2-D seismic reflection tomography—A joint inversion of velocity and interface [J]. North China Earthquake Sciences, 12(4): 9–17 (in Chinese).
LIU Zhi, ZHANG Xiang-kang, ZHOU Xue-song et al. 2003. A study of crustal structure in terms of physical property and discussion on seismogenic environment in the northeastern Pamirs [J]. Acta Seimologica Sinica, 16(3): 251–259.
TANG Ji, DENG Qian-hui, ZHAO Guo-ze et al. 2001. Electric conductivity and magma chamber at Tianchi volcano area in Changbaishan mountain [J]. Seismology and Geology, 23(2): 191–200 (in Chinese).
Walck M C. 1988. Three-Dimensional V p/V s variations for the Coso region, California [J]. J Geophys Res, 93: 2047–2052.
WANG Fu-yun, ZHANG Xian-kang YANG Zhuo-xin. 2002. 2-D crustal structure of Changbaishan Tianchi volcanic region determined by seismic traveltime inversion [J]. Acta Seimologica Sinica, 15(2): 152–161.
Zelt C A and Smith R B. 1992. Seismic travel time inversion for 2-D crustal velocity structure [J]. Geophys J Int, 108: 16–34.
ZHANG Xiang-kang, ZHANG Cheng-ke, ZHOU Xue-song et al. 2002. Deep seismic sounding investigation into the deep structure of the magma system in Changbaishan Tianchi volcanic region [J]. Acta Seimologica Sinica, 15(2): 135–143.
ZHAO Jin-ren, ZHANG Xian-kang, YANG Zhuo-xin et al. 3D tomography of velocity structure in the upper crust beneath the Changbaishan Tianchi volcanic region [J]. Chinese J Geophys, 46(6): 796–802 (in Chinese).
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Foundation item: Key Project from China Earthquake Administration and the Project (95-11-02-01) from Ministry of Science and Technology (2001DIA10003).
Contribution No. RCEG200401, Geophysical Exploration Center, China Earthquake Administration.
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Liu, Z., Zhang, Xk., Wang, Fy. et al. 2-D crustal Poisson’s ratio from seismic travel time inversion in Changbaishan Tianchi volcanic region. Acta Seimol. Sin. 18, 345–353 (2005). https://doi.org/10.1007/s11589-005-0084-y
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DOI: https://doi.org/10.1007/s11589-005-0084-y