中国及邻区瑞利面波高分辨率层析成像及其地球动力学意义
|
摘要
用分布于欧亚大陆及西太平洋地区106个宽频带数字地震台站约2万多个长周期波形记录,挑选出沿10600条大圆路径传播的瑞利面波,采用频散分析及波形拟合反演方法,对中国及相邻地区地壳上地幔进行高分辨率三维层析成像。瑞利面波高分辨率速度成像表明,从上地壳到70km深,在东亚东部及西太平洋边缘海地区均为高速分布,西部以青藏高原为中心呈极低速分布。从100～250km深,在东亚东部及西太平洋边缘海,自北向南显示出一条宽2500～4000km,长约8000km的巨型低速异常带。在深度300～400km的平面图上,速度差异幅度不大,塔里木—扬子地块仍然显示为高速分布。东西两部分岩石圈与软流圈的结构有着巨大的差异。西部主要是印度板块与欧亚板块碰撞引起的岩石圈汇聚增厚区,东部则主要是由于软流圈上涌(地幔热物质上升)引起的岩石圈拉张减薄区。古新世印度与欧亚大陆的碰撞汇聚,岩石圈板片以低角度下插到青藏高原之下,引起高原隆起和地壳增厚,西部地区成为岩石圈汇聚区。中生代中晚期东亚大陆东缘岩石圈解体,软流圈物质上涌,岩石圈减薄张裂,形成巨型低速带,并演化为东亚裂谷系。现今的西太平洋边缘海、沟弧盆体系是新生代中晚期太平洋板块、澳大利亚板块与欧亚板块相互作用形成的。
Rayleigh surface waves propagating along 10,600 great-circle paths were selected using more than 20,000 long-period waveform records from 106 wide-band digital seismic stations distributed in Eurasia and the Western Pacific, and high-resolution 3D tomographic imaging of the crust and upper mantle in China and its adjacent regions was performed using the inversion of both dispersion analysis and waveform fitting. The high-resolution Rayleigh surface wave tomographic imaging indicates that: from the upper crust to 70 km depth, high velocities are displayed in the eastern part of East Asia and Western Pacific marginal seas, while very low velocities distributed in the western region centering around the Qinghai-Tibet Plateau; from the 100 to 250 km depth, a giant low-velocity anomaly belt ~250 to 400 km wide and ~8000 km long are shown in the eastern part of East Asia and Western Pacific marginal seas; from the 300 to 400 km depth, there is no appreciable velocity difference and high velocities are still displayed from the Tarim block to Yangtze block. There exist significant differences in lithospheric and asthenospheric structure between the eastern and western parts with longitude 110°E as the boundary. The western part is the lithospheric thickening convergent region formed by India-Eurasia collision, whereas the eastern part the lithospheric extension-thinning region arising from upwelling of asthenospheric material (rise of mantle thermal material). Due to the Paleocene India-Eurasia collision and convergence, the Indian lithospheric sheet was subducted beneath the Qinghai-Tibet Plateau at low angles, causing the plateau uplift and crustal thickening; thus the western part became a lithospheric region. In the Mid-Late Mesozoic, the lithosphere beneath the eastern margin of the East Asian continent was disassembled; as a result, the asthenospheric material upwelled and the lithosphere underwent extension and thinning, thus forming a giant low-velocity zone, which later evolved into the East Asian rift system. The present marginal seas and trench-arc-basin system of the Western Pacific was formed by interaction of the Pacific plate, Australian plate and Eurasia plate in the Mid-Late Cenozoic.
Rayleigh surface waves propagating along 10,600 great-circle paths were selected using more than 20,000 long-period waveform records from 106 wide-band digital seismic stations distributed in Eurasia and the Western Pacific, and high-resolution 3D tomographic imaging of the crust and upper mantle in China and its adjacent regions was performed using the inversion of both dispersion analysis and waveform fitting. The high-resolution Rayleigh surface wave tomographic imaging indicates that: from the upper crust to 70 km depth, high velocities are displayed in the eastern part of East Asia and Western Pacific marginal seas, while very low velocities distributed in the western region centering around the Qinghai-Tibet Plateau; from the 100 to 250 km depth, a giant low-velocity anomaly belt ~250 to 400 km wide and ~8000 km long are shown in the eastern part of East Asia and Western Pacific marginal seas; from the 300 to 400 km depth, there is no appreciable velocity difference and high velocities are still displayed from the Tarim block to Yangtze block. There exist significant differences in lithospheric and asthenospheric structure between the eastern and western parts with longitude 110°E as the boundary. The western part is the lithospheric thickening convergent region formed by India-Eurasia collision, whereas the eastern part the lithospheric extension-thinning region arising from upwelling of asthenospheric material (rise of mantle thermal material). Due to the Paleocene India-Eurasia collision and convergence, the Indian lithospheric sheet was subducted beneath the Qinghai-Tibet Plateau at low angles, causing the plateau uplift and crustal thickening; thus the western part became a lithospheric region. In the Mid-Late Mesozoic, the lithosphere beneath the eastern margin of the East Asian continent was disassembled; as a result, the asthenospheric material upwelled and the lithosphere underwent extension and thinning, thus forming a giant low-velocity zone, which later evolved into the East Asian rift system. The present marginal seas and trench-arc-basin system of the Western Pacific was formed by interaction of the Pacific plate, Australian plate and Eurasia plate in the Mid-Late Cenozoic.
引文
[1]冯锐,朱介寿,丁韫玉,等.利用地震面波研究中国地壳结构[J].地震学报,1981,3(4):335-350.Feng Rui,Zhu Jieshou,Ding Wenyu,et al.Study the crustal structure in China by using the seismic surface wave[J].Seismological J.1981,3(4):335-350(in Chinese with English abstract).
[2]宋仲和,陈国英,安昌强,等.中国大陆及其海域地壳-上地幔三维速度结构[J].中国科学(B),1993,23(2):180-188.Song Zhonghe,Chen Guoyin,An Changqiang,et al.The3-D structure of crust and mantle in Continental China and adjacent seas[J].Science in China(Series B),1993,23(2):180-188(in Chinese).
[3]周兵,朱介寿,秦建业.青藏高原及邻近区域S波三维速度结构[J].地球物理学报,1991,34(4):426-441.Zhou Bin,Zhu Jieshou,Chun Kin-Yip.Three dimensional shear velocity structure beneath Qinghai-Tibet and its adjacent area.Chinese Journal of Geophys,1991,34(4):426-441(in Chinese with English abstract).
[4]朱介寿.全球地幔三维结构模型及动力学研究新进展[J].地球科学进展[J].1996,11(5):421-431.Zhu Jieshou.The recent development of three-dimensional models and geodynamics of the earth's mantle[J].Advance in Earth Sciences,1996,11(5):421-431(in Chinese with English abstract).
[5]Feng C C,Teng T L.Three-dimensional crust and upper mantle structure of the Eurasian Continent[J].J.Geophys.Res.,1983,88:2261-2273.
[6]Nakanishi I,Anderson D L.Worldwide distribution of group velocity of mantle Rayleigh waves as determined by spherical harmonic inversion[J].Bull.Seismol.Soc.Am.,1982,72:1185-1194.
[7]Snieder R,Nolet G.Linearized scattering of surface waves on a spherical Earth[J].J.Geophys.,1987,61:55-63.
[8]Snieder R.Large-scale waveform inversions of surface waves forlateral heterogeneity,2,Application to surface waves in Europe and the Mediterranean[J].J.Geophys.Res.,1988,93:12067-12080.
[9]朱介寿,曹家敏,蔡学林,等.东亚及西太平洋边缘海高分辨率面波层析成像[J].地球物理学报,2002,45(5):646-664.Zhu Jieshou,Cao Jiamin,Cai Xuelin,et al.High resolution surface wave tomography in east Asia and west Pacific marginal seas[J].Chinese Journal of Geophys,2002,45(5):646-664(in Chinese with English abstract).
[10]洪学海,朱介寿,曹家敏,等.中国大陆地壳上地幔S波品质因子三维层析成像[J].地球物理学报,2003,46(5):642-651.Hong Xuehai,Zhu Jieshou,Cao Jiamin.et al.Tomography of3-D S-wave quality factor of the crust and Upper Mantle in China[J].Chinese J.Geophys,2003,46(5):642-651(in Chinese with English abstract).
[11]朱介寿,曹家敏,蔡学林,等.欧亚大陆及西太平洋边缘海岩石圈结构[J].地球科学进展,2004,19(3):387-391.Zhu Jieshou,Cao Jiamin,Cai Xuelin,et al.The structure of lithosphere in Eurasia and west Pacific[J].Advance in Earth Sciences,2004,19(3):387-392(in Chinese with English abstract).
[12]朱介寿,曹家敏,蔡学林,等.中国及邻近陆域海域地球内部三维结构及动力学研究[J].地球科学进展,2003,18(4):497-503.Zhu Jieshou,Cao Jiamin,Cai Xuelin,et al.Study for three-dimensional structure of earth interior and geodynamics in China and adjacent land and sea regions[J].Advance in Earth Sciences,2003,18(4):387-392(in Chinese with English abstract).
[13]滕吉文,胡家富,张中杰.中国西北地区岩石层瑞利波三维速度结构与沉积盆地[J].地球物理学报,1995,38(6):737-749.Teng Jiwen,Hu Jiafu,Zhang Zhongjie.The3-D structure of Rayleigh wave and sedimentary basins in thr Northwest China[J].Chinese Journal of Geophys,1995,38(6):737-749(in Chinese with English abstract).
[14]张禹慎,马石庄.全球地震面波相速度变化及其大地构造学意义[J].地球物理学报,1997,40:181-192.Zhang Yushen,Ma Shizhuang.Global surface wave phase velocity variations and their tectonic implications[J].Chinese Journal of Geophys,1997,40(2):181-192(in Chinese with English abstract).
[15]Cao Xiaolin,Zhu Jieshou,Zhao Lianfeng,et al.Three dimensional shear wave velocity structure of crust and upper mantle in South China Sea and its adjacent regions by surface waveform inversion[J].Acta Seismol.Sinca.2001,23(2):113-124.
[16]Ekstr#m G.J,Tromp J E,Larson W F.Measurements and globalmodels of surface wave propagation[J].J.Geophys.Res.,1997,102:8137-8158.
[17]Ekstrom G.Mapping the lithosphere and asthenosphere with surface waves:Lateral structure and anisotropy the History and Dynamics of Global Plate Motions in[C]//Geophys.Monogr.Ser.,vol.121,edited by M.A.Richards,R.G.Gordon,and R.D.van der Hilst,pp.277-288,AGU,Washington,D.C.,2000.
[18]Friederich W.The S-velocity structure of the East Asian mantle from inversion of shear and surface waveforms[J].Geophys.J.Int.,2003,153:88-102.
[19]Huang Z,W Su,Y.Peng,et al.Rayleigh wave tomography of China and adjacent regions[J].J.Geophys.Res.,2003,108(B2):2073.
[20]Nakamura Y,Shibutani T.3-D shear wave velocity structure in the upper mantle beneath the Philippine Sea[J].Earth Planets Space,1998,50:939-952.
[21]Ritzwoller M H,Lavely E M.Long period surface waves and mantle boundary undulations[J].Geophys.J.Int.,1994,116:205-216.
[22]Ritzwoller M H,Levshin A L.Eurasian surface wave tomography:Group velocities[J].J.Geophys.Res.,1998,83:4839-4878.
[23]Wu F,Levshin A.Surface wave tomography of East Asia.Phys.Earth Planet[J].Inter.,1994,84:59-78.
[24]Zhang Y S,Tanimoto T.High-resolution global upper mantle structure and plate tectonics[J].J.Geophys.Res.,1993,98:9793-9823.
[25]Zhang Y S,Lay T.Global surface wave phase velocity variations[J].J.Geophys.Res.,1996,101:8415-8436.
[26]刘光鼎主编.中国海区及邻域地质地球物理特征[M].北京:科学出版社,1992.Liu Guangding ed.The Geological and Geophysical Characteristics in Seas of China and Adjacent Areas[M].Beijing:Sciences Press,1992.
[27]任纪舜,王作勋,陈炳蔚,等.从全球看中国大地构造—中国及邻区大地构造图简要说明[M].北京:地质出版社,1999.Ren Jishun,Wang Zuoxun,Chen Bingwei,et al.The Tectonics of China from a Global View-A Guide to the Tectonic Map of China and Adjacent Regions[M].Beijing:Geological Publishing House,1999(in Chinese).
[28]袁学诚主编.中国地球物理图集[M].北京:地质出版社,1996.Yuan Xuecheng ed.Atlas of Geophysical Maps of China[M].Beijing:Geological Publishing House,1996(in Chinese).
[2]宋仲和,陈国英,安昌强,等.中国大陆及其海域地壳-上地幔三维速度结构[J].中国科学(B),1993,23(2):180-188.Song Zhonghe,Chen Guoyin,An Changqiang,et al.The3-D structure of crust and mantle in Continental China and adjacent seas[J].Science in China(Series B),1993,23(2):180-188(in Chinese).
[3]周兵,朱介寿,秦建业.青藏高原及邻近区域S波三维速度结构[J].地球物理学报,1991,34(4):426-441.Zhou Bin,Zhu Jieshou,Chun Kin-Yip.Three dimensional shear velocity structure beneath Qinghai-Tibet and its adjacent area.Chinese Journal of Geophys,1991,34(4):426-441(in Chinese with English abstract).
[4]朱介寿.全球地幔三维结构模型及动力学研究新进展[J].地球科学进展[J].1996,11(5):421-431.Zhu Jieshou.The recent development of three-dimensional models and geodynamics of the earth's mantle[J].Advance in Earth Sciences,1996,11(5):421-431(in Chinese with English abstract).
[5]Feng C C,Teng T L.Three-dimensional crust and upper mantle structure of the Eurasian Continent[J].J.Geophys.Res.,1983,88:2261-2273.
[6]Nakanishi I,Anderson D L.Worldwide distribution of group velocity of mantle Rayleigh waves as determined by spherical harmonic inversion[J].Bull.Seismol.Soc.Am.,1982,72:1185-1194.
[7]Snieder R,Nolet G.Linearized scattering of surface waves on a spherical Earth[J].J.Geophys.,1987,61:55-63.
[8]Snieder R.Large-scale waveform inversions of surface waves forlateral heterogeneity,2,Application to surface waves in Europe and the Mediterranean[J].J.Geophys.Res.,1988,93:12067-12080.
[9]朱介寿,曹家敏,蔡学林,等.东亚及西太平洋边缘海高分辨率面波层析成像[J].地球物理学报,2002,45(5):646-664.Zhu Jieshou,Cao Jiamin,Cai Xuelin,et al.High resolution surface wave tomography in east Asia and west Pacific marginal seas[J].Chinese Journal of Geophys,2002,45(5):646-664(in Chinese with English abstract).
[10]洪学海,朱介寿,曹家敏,等.中国大陆地壳上地幔S波品质因子三维层析成像[J].地球物理学报,2003,46(5):642-651.Hong Xuehai,Zhu Jieshou,Cao Jiamin.et al.Tomography of3-D S-wave quality factor of the crust and Upper Mantle in China[J].Chinese J.Geophys,2003,46(5):642-651(in Chinese with English abstract).
[11]朱介寿,曹家敏,蔡学林,等.欧亚大陆及西太平洋边缘海岩石圈结构[J].地球科学进展,2004,19(3):387-391.Zhu Jieshou,Cao Jiamin,Cai Xuelin,et al.The structure of lithosphere in Eurasia and west Pacific[J].Advance in Earth Sciences,2004,19(3):387-392(in Chinese with English abstract).
[12]朱介寿,曹家敏,蔡学林,等.中国及邻近陆域海域地球内部三维结构及动力学研究[J].地球科学进展,2003,18(4):497-503.Zhu Jieshou,Cao Jiamin,Cai Xuelin,et al.Study for three-dimensional structure of earth interior and geodynamics in China and adjacent land and sea regions[J].Advance in Earth Sciences,2003,18(4):387-392(in Chinese with English abstract).
[13]滕吉文,胡家富,张中杰.中国西北地区岩石层瑞利波三维速度结构与沉积盆地[J].地球物理学报,1995,38(6):737-749.Teng Jiwen,Hu Jiafu,Zhang Zhongjie.The3-D structure of Rayleigh wave and sedimentary basins in thr Northwest China[J].Chinese Journal of Geophys,1995,38(6):737-749(in Chinese with English abstract).
[14]张禹慎,马石庄.全球地震面波相速度变化及其大地构造学意义[J].地球物理学报,1997,40:181-192.Zhang Yushen,Ma Shizhuang.Global surface wave phase velocity variations and their tectonic implications[J].Chinese Journal of Geophys,1997,40(2):181-192(in Chinese with English abstract).
[15]Cao Xiaolin,Zhu Jieshou,Zhao Lianfeng,et al.Three dimensional shear wave velocity structure of crust and upper mantle in South China Sea and its adjacent regions by surface waveform inversion[J].Acta Seismol.Sinca.2001,23(2):113-124.
[16]Ekstr#m G.J,Tromp J E,Larson W F.Measurements and globalmodels of surface wave propagation[J].J.Geophys.Res.,1997,102:8137-8158.
[17]Ekstrom G.Mapping the lithosphere and asthenosphere with surface waves:Lateral structure and anisotropy the History and Dynamics of Global Plate Motions in[C]//Geophys.Monogr.Ser.,vol.121,edited by M.A.Richards,R.G.Gordon,and R.D.van der Hilst,pp.277-288,AGU,Washington,D.C.,2000.
[18]Friederich W.The S-velocity structure of the East Asian mantle from inversion of shear and surface waveforms[J].Geophys.J.Int.,2003,153:88-102.
[19]Huang Z,W Su,Y.Peng,et al.Rayleigh wave tomography of China and adjacent regions[J].J.Geophys.Res.,2003,108(B2):2073.
[20]Nakamura Y,Shibutani T.3-D shear wave velocity structure in the upper mantle beneath the Philippine Sea[J].Earth Planets Space,1998,50:939-952.
[21]Ritzwoller M H,Lavely E M.Long period surface waves and mantle boundary undulations[J].Geophys.J.Int.,1994,116:205-216.
[22]Ritzwoller M H,Levshin A L.Eurasian surface wave tomography:Group velocities[J].J.Geophys.Res.,1998,83:4839-4878.
[23]Wu F,Levshin A.Surface wave tomography of East Asia.Phys.Earth Planet[J].Inter.,1994,84:59-78.
[24]Zhang Y S,Tanimoto T.High-resolution global upper mantle structure and plate tectonics[J].J.Geophys.Res.,1993,98:9793-9823.
[25]Zhang Y S,Lay T.Global surface wave phase velocity variations[J].J.Geophys.Res.,1996,101:8415-8436.
[26]刘光鼎主编.中国海区及邻域地质地球物理特征[M].北京:科学出版社,1992.Liu Guangding ed.The Geological and Geophysical Characteristics in Seas of China and Adjacent Areas[M].Beijing:Sciences Press,1992.
[27]任纪舜,王作勋,陈炳蔚,等.从全球看中国大地构造—中国及邻区大地构造图简要说明[M].北京:地质出版社,1999.Ren Jishun,Wang Zuoxun,Chen Bingwei,et al.The Tectonics of China from a Global View-A Guide to the Tectonic Map of China and Adjacent Regions[M].Beijing:Geological Publishing House,1999(in Chinese).
[28]袁学诚主编.中国地球物理图集[M].北京:地质出版社,1996.Yuan Xuecheng ed.Atlas of Geophysical Maps of China[M].Beijing:Geological Publishing House,1996(in Chinese).
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心