东北亚地区地壳密度结构与垂向构造应力场
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摘要
本文利用EIGEN-6C4重力数据和ETOPO1地形数据,在考虑物质密度横向不均匀的情况下,在东北亚地区展开地壳均衡研究,并重点分析了长白山的隆升机制.首先,针对穿越长白山和库页岛的两条近乎东西向的剖面(剖面A、B)展开详细研究,以CRUST1.0模型为初始条件,利用布格重力异常数据,基于Airy模型和Airy-Pratt模型分别反演了相应剖面的地壳密度结构,发现两剖面的地壳密度呈现一定程度的横向不均匀特性;接着基于上述密度结构和高程数据,利用Airy均衡理论计算了相应剖面的均衡面深度,并进一步比较莫霍面(Moho)和均衡面的差异,计算了剖面的垂向构造应力分布;然后,把上述方法应用到整个东北亚地区,计算了1°采样的21条东西向剖面的垂向构造应力,插值得到整个东北亚地区的垂向构造应力分布.结果表明,东北亚大部分地区垂向构造应力基本为零,总体处于均衡状态,长白山地区垂向构造应力为-15~-25MPa,日本列岛垂向构造应力为-40~-50MPa,太平洋海沟垂向构造应力为15~25 MPa;最后,本文运用自由空气重力异常导纳方法,计算了长白山地区的有效弹性厚度(Te)和加载比,发现长白山地区的Te为10km,表明该地区的岩石圈较为柔软;加载比结果显示,岩石圈初始加载主要来自莫霍面,占总加载的78%,表明长白山的隆升主要源自地幔物质上涌.
Considering the lateral density variation of crust,we investigate the isostatic state of Northeast Asia with the utilization of EIGEN-6 C4 gravity data and ETOPO1 topography data,and analyze the uplifting mechanism of the Changbai Mountain.First,we study in detail two profiles in roughly east-west direction which stretch over Changbai Mountain and Sakhalin Island(profile A & B).Specifically,taking CRUST1.0 model as initial conditions,we inverse the density structure of Crust along the two profiles with Bouguer gravity anomalies,using Airy and Airy-Pratt isostasy theories,respectively.The results show that,to some degree,there is lateral inhomogeneity in the crust density structure along the profiles.Then,according to the inversed density structures and topography data we calculate the depth of isostasy along each profile.Based on the comparison of the depth of isostasy with the one of Moho,we calculate the vertical tectonic stress of the two profiles.And then,with the method illustrated above,we calculate the vertical tectonic stress along 21 profiles in exactly east-west direction within our study area,with sampling interval of 1 degree.By interpolating the above results we obtain the distribution of the vertical tectonic stress of the whole Northeast Asia.In total,the crust of Northeast Asia,whose vertical tectonic stress is about 0,is in isostatic state.Among which,the vertical tectonic stress at the Changbai Mountain is-(15~25)MPa,at Japan Islands is-(40~50)MPa,and at the Pacific trench is 15~25 MPa.Finally,we estimate the effective elastic thickness(Te)and the load ratio of the area around the Changbai Mountain,using the method of Free-air gravity anomaly admittance.The result shows that the Teof the Changbai Mountain is about 10 km,which mean that the lithosphere of the area is relatively soft.The initial load is mainly from the Moho,about 78% of total load,which suggest that the uplifting of the Changbai Mountain was mainly resulted from the uplifting of material of the Mantle.
Considering the lateral density variation of crust,we investigate the isostatic state of Northeast Asia with the utilization of EIGEN-6 C4 gravity data and ETOPO1 topography data,and analyze the uplifting mechanism of the Changbai Mountain.First,we study in detail two profiles in roughly east-west direction which stretch over Changbai Mountain and Sakhalin Island(profile A & B).Specifically,taking CRUST1.0 model as initial conditions,we inverse the density structure of Crust along the two profiles with Bouguer gravity anomalies,using Airy and Airy-Pratt isostasy theories,respectively.The results show that,to some degree,there is lateral inhomogeneity in the crust density structure along the profiles.Then,according to the inversed density structures and topography data we calculate the depth of isostasy along each profile.Based on the comparison of the depth of isostasy with the one of Moho,we calculate the vertical tectonic stress of the two profiles.And then,with the method illustrated above,we calculate the vertical tectonic stress along 21 profiles in exactly east-west direction within our study area,with sampling interval of 1 degree.By interpolating the above results we obtain the distribution of the vertical tectonic stress of the whole Northeast Asia.In total,the crust of Northeast Asia,whose vertical tectonic stress is about 0,is in isostatic state.Among which,the vertical tectonic stress at the Changbai Mountain is-(15~25)MPa,at Japan Islands is-(40~50)MPa,and at the Pacific trench is 15~25 MPa.Finally,we estimate the effective elastic thickness(Te)and the load ratio of the area around the Changbai Mountain,using the method of Free-air gravity anomaly admittance.The result shows that the Teof the Changbai Mountain is about 10 km,which mean that the lithosphere of the area is relatively soft.The initial load is mainly from the Moho,about 78% of total load,which suggest that the uplifting of the Changbai Mountain was mainly resulted from the uplifting of material of the Mantle.
引文
Amante C,Eakins B W.2009.ETOPO1 1arc-minute global relief model:procedures,data sources and analysis.NOAA Technical Memorandum NESDIS NGDC-24,National Geophysical Data Center.USA:NOAA.
Andersen O B.2010.The DTU10 gravity field and mean sea surface.∥Second international symposium of the gravity field of the Earth(IGFS2).Fairbanks,Alaska,20-22.
Brune J N.1970.Tectonic stress and the spectra of seismic shear waves from earthquakes.Journal of Geophysical Research,75(26):4997-5009.
Cai S H,Tauxe L,Deng C L,et al.2016.New archaeomagnetic direction results from China and their constraints on palaeosecular variation of the geomagnetic field in Eastern Asia.Geophysical Journal International,207(2):1332-1342.
Dang Y M,Yang Q,Cao X W.2009.Research on tectonic stress field distribution within crust.Journal of Geodesy and Geodynamics(in Chinese),29(2):4-6.
Duan Y H,Zhao D P,Zhang X K,et al.2009.Seismic structure and origin of active intraplate volcanoes in Northeast Asia.Tectonophysics,470(3-4):257-266.
Fielding E J,McKenzie D.2012.Lithospheric flexure in the Sichuan basin and Longmen Shan at the eastern edge of Tibet.Geophysical Research Letters,39(9):L09311,doi:10.1029/2012GL051680.
F9rste C,Bruinsma S,Abrikosov O,et al.2014.EIGEN-6C4-The latest combined global gravity field model including GOCE data up to degree and order 1949 of GFZ Potsdam and GRGSToulouse.∥EGU General Assembly.Vienna:European Geosciences Union.
Forsyth D W.1985.Subsurface loading and estimates of the flexural rigidity of continental lithosphere.Journal of Geophysical Research:Solid Earth,90(B14):12623-12632.
Fu G Y,Gao S H,Freymueller J T,et al.2014.Bouguer gravity anomaly and isostasy at western sichuan basin revealed by new gravity surveys.Journal of Geophysical Research:Solid Earth,119(4):3925-3938.
Gao S H,She Y W,Fu G Y.2016.A new method for computing the vertical tectonic stress of the crust by use of hybrid gravity and GPS data.Chinese Journal of Geophysics(in Chinese),59(6):2006-2013,doi:10.6038/cjg20160607.
Ito T,Hayashi K.1991.Physical background to the breakdown pressure in hydraulic fracturing tectonic stress measurements.InternationalJournalofRockMechanicsand MiningScience&GeomechanicsAbstracts,28(4):285-293.
Iwasaki T,Adachi K,Moriya T,et al.2004.Upper and middle crustal deformation of an arc-arc collision across Hokkaido,Japan,inferred from seismic refraction/wide-angle reflection experiments.Tectonophysics,388(1-4):59-73.
Jiang X D,Jin Y,McNutt M K.2004.Lithospheric deformation beneath the Altyn Tagh and West Kunlun faults from recent gravity surveys.Journal of Geophysical Research:Solid Earth,109(B5):B05406.
Laske G,Masters G,Ma Z T,et al.2013.Update on CRUST1.0-A 1-degree global model of Earth′s crust.∥EGU General Assembly.Vienna:European Geosciences Union.
Li J Y.2006.Permian geodynamic setting of Northeast China and adjacent regions:closure of the Paleo-Asian Ocean and subduction of the Paleo-Pacific Plate.Journal of Asian Earth Sciences,26(3-4):207-224.
Marquardt D W.1963.An algorithm for least-square estimation of nonlinear parameters.Journal of the Society for Industrial and Applied Mathematics,11(2):431-441.
Maruyama S,Seno T.1986.Orogeny and relative plate motions:Example of the Japanese Islands.Tectonophysics,127(3-4):305-329.
Maruyama S,Isozaki Y,Kimura G,et al.,2006.Paleogeographic maps of the Japanese Islands:plate tectonic synthesis from 750Ma to the present.Island Arc,6(1):121-142.
McKenzie D,Fairhead D.1997.Estimates of the effective elastic thickness of the continental lithosphere form Bouguer and free air gravity anomalies.Journal of Geophysical Research:Solid Earth,102(B12):27523-27552.
McKenzie D.2003.Estimating Tein the presence of internal loads.Journal of Geophysical Research:Solid Earth,108(B9):2438,doi:10.1029/2002JB001766.
Pavlis N K,Holmes S A,Kenyon S C,et al.2013.The development and evaluation of the Earth Gravitational Model 2008(EGM2008).Journal of Geophysical Research:Solid Earth,117(B4):B04406,doi:10.1029/2011JB008916.
PlomerováJ,Liebermann R C,Babu2ka V.1998.Geodynamics of lithosphere and earth′s mantle:seismic anisotropy as a record of the past and present dynamic processes.Pure and Applied Geophysics,151(2-4):213-219.
Priestley K,Debayle E,Mckenzie D,et al.2006.Upper mantle structure of Eastern Asia from multimode surface waveform tomography.Journal of Geophysical Research:Solid Earth,111(B10):B10304,doi:10.1029/2005JB004082.
Scheirer D,Forsyth D W,Hosford A.1995.Multitaper estimates of the lithospheric strength of the Basin and Range province.Eos,76,17.
She Y W,Fu G Y,Su X N,et al.2016.Crustal isostasy and uplifting mechanism of the Liupanshan area.Progress in Geophysics(in Chinese),31(4):1464-1472,doi:10.3969/j.issn.0253-4975.2015.09.080.
Sibson R H.2003.Brittle-failure controls on maximum sustainable overpressure in different tectonic regimes.AAPG Bulletin,87(6):901-908.
Simons F J,Zuber M T,Korenaga J.2000.Isostatic response of the Australian lithosphere:Estimation of effective elastic thickness and anisotropy using multitaper spectral analysis.Journal of Geophysical Research:Solid Earth,105(B8):19163-19184.
Talwani M,Worzel J L,Landisman M.2012.Rapid gravity computations for two-dimensional bodies with application to the Mendocino submarine fracture zone.Journal of Geophysical Research,64(1):49-59.
Tang Y C,Obayashi M,Niu F L,et al.,2014.Changbaishan volcanism in Northeast China linked to subduction-induced mantle upwelling.Nature Geoscience,7(6):470-475.
Tao K,Niu F L,Ning J Y,et al.2014.Crustal structure beneath NE China imaged by NEEESSArray receiver function data.Earth and Planetary Science Letters,398:48-57.
Thomson D J.1982.Spectrum estimation and harmonic analysis.Proceedings of the IEEE,70(9):1055-1096.
Turcotte D L,Schubert G.2002.Geodynamics.2nd ed.Cambridge:Cambridge University Press.
Wada I,He J H,Hasegawa A,et al.2015.Mantle wedge flow pattern and thermal structure in Northeast Japan:Effects of oblique subduction and 3-D slab geometry.Earth and Planetary Science Letters,426:76-88.
Watts A B.2001.Isostasy and Flexure of the Lithosphere.Cambridge:Cambridge University Press.
Won I J,Bevis M.1987.Computing the gravitational and magnetic anomalies due to a polygon:Algorithms and Fortran subroutines.Geophysics,52(2):232-238.
Zang S X,Ning J Y.1996.Study on the subduction zone in western Pacific and its implication for the geodynamics.Acta Geophysica Sinica(in Chinese),39(2):188-202.
Zhang L M,Tang X M.1983.The underthrusting movement of the western Pacific plate and the deep focus earthquake zone of northeast China.Acta Geophysica Sinica(in Chinese),26(4):331-340.
Zhang Y Q,Wang Q S,Teng J W.2010.The crustal isostatic anomaly beneath eastern Tibet and western Sichuan and its relationship with the distribution of earthquake.Chinese Journal of Geophysics(in Chinese),53(11):2631-2638,doi:10.3969/j.issn.0001-5733.2010.11.011.
Zhao D P,Tian Y.2013.Changbai intraplate volcanism and deep earthquakes in East Asia:A possible link?.Geophysical Journal International,195(2):706-724.
Zhao Q,Wu W W,Wu Y L.2017.Using combined GRACE and GPS data to investigate the vertical crustal deformation at the northeastern margin of the Tibetan Plateau.Journal of Asian Earth Sciences,134:122-129,doi:10.1016/j.jseaes.2016.11.010.
Zheng Y,Shen W S,Zhou L Q,et al.2011.Crust and uppermost mantle beneath the North China Craton,northeastern China,and the Sea of Japan from ambient noise tomography.Journal of Geophysical Research:Solid Earth,116(B12):B12312,doi:10.1029/2011JB008637.
Zhu Y Q,Wen X Z,Sun H P,et al.2013.Gravity changes before the Lushan,Sichuan,MS=7.0Earthquake of 2013.Chinese Journal of Geophysics(in Chinese):56(6):1887-1894,doi:10.6038/cjg20130611.
党亚民,杨强,曹学伟.2009.地壳内构造应力的分布研究.大地测量与地球动力学,29(2):4-6.
高尚华,佘雅文,付广裕.2016.利用重力/GPS联合观测数据计算地壳垂向构造应力的新方法.地球物理学报,59(6):2006-2013,doi:10.6038/cjg20160607.
佘雅文,付广裕,苏小宁等.2016.六盘山地区地壳重力均衡与隆升机制研究.地球物理学进展,31(4):1464-1472,doi:10.3969/j.issn.0253-4975.2015.09.080.
臧绍先,宁杰远.1996.西太平洋俯冲带的研究及其动力学意义.地球物理学报,39(2):188-202.
张立敏,唐晓明.1983.西太平洋板块俯冲运动与中国东北深震带.地球物理学报,26(4):331-340.
张永谦,王谦身,滕吉文.2010.川西藏东地区的地壳均衡异常及其与地震分布的关系.地球物理学报,53(11):2631-2638,doi:10.3969/j.issn.0001-5733.2010.11.011.
祝意青,闻学泽,孙和平等.2013.2013年四川芦山MS7.0地震前的重力变化.地球物理学报,56(6):1887-1894,doi:10.6038/cjg20130611.
Andersen O B.2010.The DTU10 gravity field and mean sea surface.∥Second international symposium of the gravity field of the Earth(IGFS2).Fairbanks,Alaska,20-22.
Brune J N.1970.Tectonic stress and the spectra of seismic shear waves from earthquakes.Journal of Geophysical Research,75(26):4997-5009.
Cai S H,Tauxe L,Deng C L,et al.2016.New archaeomagnetic direction results from China and their constraints on palaeosecular variation of the geomagnetic field in Eastern Asia.Geophysical Journal International,207(2):1332-1342.
Dang Y M,Yang Q,Cao X W.2009.Research on tectonic stress field distribution within crust.Journal of Geodesy and Geodynamics(in Chinese),29(2):4-6.
Duan Y H,Zhao D P,Zhang X K,et al.2009.Seismic structure and origin of active intraplate volcanoes in Northeast Asia.Tectonophysics,470(3-4):257-266.
Fielding E J,McKenzie D.2012.Lithospheric flexure in the Sichuan basin and Longmen Shan at the eastern edge of Tibet.Geophysical Research Letters,39(9):L09311,doi:10.1029/2012GL051680.
F9rste C,Bruinsma S,Abrikosov O,et al.2014.EIGEN-6C4-The latest combined global gravity field model including GOCE data up to degree and order 1949 of GFZ Potsdam and GRGSToulouse.∥EGU General Assembly.Vienna:European Geosciences Union.
Forsyth D W.1985.Subsurface loading and estimates of the flexural rigidity of continental lithosphere.Journal of Geophysical Research:Solid Earth,90(B14):12623-12632.
Fu G Y,Gao S H,Freymueller J T,et al.2014.Bouguer gravity anomaly and isostasy at western sichuan basin revealed by new gravity surveys.Journal of Geophysical Research:Solid Earth,119(4):3925-3938.
Gao S H,She Y W,Fu G Y.2016.A new method for computing the vertical tectonic stress of the crust by use of hybrid gravity and GPS data.Chinese Journal of Geophysics(in Chinese),59(6):2006-2013,doi:10.6038/cjg20160607.
Ito T,Hayashi K.1991.Physical background to the breakdown pressure in hydraulic fracturing tectonic stress measurements.InternationalJournalofRockMechanicsand MiningScience&GeomechanicsAbstracts,28(4):285-293.
Iwasaki T,Adachi K,Moriya T,et al.2004.Upper and middle crustal deformation of an arc-arc collision across Hokkaido,Japan,inferred from seismic refraction/wide-angle reflection experiments.Tectonophysics,388(1-4):59-73.
Jiang X D,Jin Y,McNutt M K.2004.Lithospheric deformation beneath the Altyn Tagh and West Kunlun faults from recent gravity surveys.Journal of Geophysical Research:Solid Earth,109(B5):B05406.
Laske G,Masters G,Ma Z T,et al.2013.Update on CRUST1.0-A 1-degree global model of Earth′s crust.∥EGU General Assembly.Vienna:European Geosciences Union.
Li J Y.2006.Permian geodynamic setting of Northeast China and adjacent regions:closure of the Paleo-Asian Ocean and subduction of the Paleo-Pacific Plate.Journal of Asian Earth Sciences,26(3-4):207-224.
Marquardt D W.1963.An algorithm for least-square estimation of nonlinear parameters.Journal of the Society for Industrial and Applied Mathematics,11(2):431-441.
Maruyama S,Seno T.1986.Orogeny and relative plate motions:Example of the Japanese Islands.Tectonophysics,127(3-4):305-329.
Maruyama S,Isozaki Y,Kimura G,et al.,2006.Paleogeographic maps of the Japanese Islands:plate tectonic synthesis from 750Ma to the present.Island Arc,6(1):121-142.
McKenzie D,Fairhead D.1997.Estimates of the effective elastic thickness of the continental lithosphere form Bouguer and free air gravity anomalies.Journal of Geophysical Research:Solid Earth,102(B12):27523-27552.
McKenzie D.2003.Estimating Tein the presence of internal loads.Journal of Geophysical Research:Solid Earth,108(B9):2438,doi:10.1029/2002JB001766.
Pavlis N K,Holmes S A,Kenyon S C,et al.2013.The development and evaluation of the Earth Gravitational Model 2008(EGM2008).Journal of Geophysical Research:Solid Earth,117(B4):B04406,doi:10.1029/2011JB008916.
PlomerováJ,Liebermann R C,Babu2ka V.1998.Geodynamics of lithosphere and earth′s mantle:seismic anisotropy as a record of the past and present dynamic processes.Pure and Applied Geophysics,151(2-4):213-219.
Priestley K,Debayle E,Mckenzie D,et al.2006.Upper mantle structure of Eastern Asia from multimode surface waveform tomography.Journal of Geophysical Research:Solid Earth,111(B10):B10304,doi:10.1029/2005JB004082.
Scheirer D,Forsyth D W,Hosford A.1995.Multitaper estimates of the lithospheric strength of the Basin and Range province.Eos,76,17.
She Y W,Fu G Y,Su X N,et al.2016.Crustal isostasy and uplifting mechanism of the Liupanshan area.Progress in Geophysics(in Chinese),31(4):1464-1472,doi:10.3969/j.issn.0253-4975.2015.09.080.
Sibson R H.2003.Brittle-failure controls on maximum sustainable overpressure in different tectonic regimes.AAPG Bulletin,87(6):901-908.
Simons F J,Zuber M T,Korenaga J.2000.Isostatic response of the Australian lithosphere:Estimation of effective elastic thickness and anisotropy using multitaper spectral analysis.Journal of Geophysical Research:Solid Earth,105(B8):19163-19184.
Talwani M,Worzel J L,Landisman M.2012.Rapid gravity computations for two-dimensional bodies with application to the Mendocino submarine fracture zone.Journal of Geophysical Research,64(1):49-59.
Tang Y C,Obayashi M,Niu F L,et al.,2014.Changbaishan volcanism in Northeast China linked to subduction-induced mantle upwelling.Nature Geoscience,7(6):470-475.
Tao K,Niu F L,Ning J Y,et al.2014.Crustal structure beneath NE China imaged by NEEESSArray receiver function data.Earth and Planetary Science Letters,398:48-57.
Thomson D J.1982.Spectrum estimation and harmonic analysis.Proceedings of the IEEE,70(9):1055-1096.
Turcotte D L,Schubert G.2002.Geodynamics.2nd ed.Cambridge:Cambridge University Press.
Wada I,He J H,Hasegawa A,et al.2015.Mantle wedge flow pattern and thermal structure in Northeast Japan:Effects of oblique subduction and 3-D slab geometry.Earth and Planetary Science Letters,426:76-88.
Watts A B.2001.Isostasy and Flexure of the Lithosphere.Cambridge:Cambridge University Press.
Won I J,Bevis M.1987.Computing the gravitational and magnetic anomalies due to a polygon:Algorithms and Fortran subroutines.Geophysics,52(2):232-238.
Zang S X,Ning J Y.1996.Study on the subduction zone in western Pacific and its implication for the geodynamics.Acta Geophysica Sinica(in Chinese),39(2):188-202.
Zhang L M,Tang X M.1983.The underthrusting movement of the western Pacific plate and the deep focus earthquake zone of northeast China.Acta Geophysica Sinica(in Chinese),26(4):331-340.
Zhang Y Q,Wang Q S,Teng J W.2010.The crustal isostatic anomaly beneath eastern Tibet and western Sichuan and its relationship with the distribution of earthquake.Chinese Journal of Geophysics(in Chinese),53(11):2631-2638,doi:10.3969/j.issn.0001-5733.2010.11.011.
Zhao D P,Tian Y.2013.Changbai intraplate volcanism and deep earthquakes in East Asia:A possible link?.Geophysical Journal International,195(2):706-724.
Zhao Q,Wu W W,Wu Y L.2017.Using combined GRACE and GPS data to investigate the vertical crustal deformation at the northeastern margin of the Tibetan Plateau.Journal of Asian Earth Sciences,134:122-129,doi:10.1016/j.jseaes.2016.11.010.
Zheng Y,Shen W S,Zhou L Q,et al.2011.Crust and uppermost mantle beneath the North China Craton,northeastern China,and the Sea of Japan from ambient noise tomography.Journal of Geophysical Research:Solid Earth,116(B12):B12312,doi:10.1029/2011JB008637.
Zhu Y Q,Wen X Z,Sun H P,et al.2013.Gravity changes before the Lushan,Sichuan,MS=7.0Earthquake of 2013.Chinese Journal of Geophysics(in Chinese):56(6):1887-1894,doi:10.6038/cjg20130611.
党亚民,杨强,曹学伟.2009.地壳内构造应力的分布研究.大地测量与地球动力学,29(2):4-6.
高尚华,佘雅文,付广裕.2016.利用重力/GPS联合观测数据计算地壳垂向构造应力的新方法.地球物理学报,59(6):2006-2013,doi:10.6038/cjg20160607.
佘雅文,付广裕,苏小宁等.2016.六盘山地区地壳重力均衡与隆升机制研究.地球物理学进展,31(4):1464-1472,doi:10.3969/j.issn.0253-4975.2015.09.080.
臧绍先,宁杰远.1996.西太平洋俯冲带的研究及其动力学意义.地球物理学报,39(2):188-202.
张立敏,唐晓明.1983.西太平洋板块俯冲运动与中国东北深震带.地球物理学报,26(4):331-340.
张永谦,王谦身,滕吉文.2010.川西藏东地区的地壳均衡异常及其与地震分布的关系.地球物理学报,53(11):2631-2638,doi:10.3969/j.issn.0001-5733.2010.11.011.
祝意青,闻学泽,孙和平等.2013.2013年四川芦山MS7.0地震前的重力变化.地球物理学报,56(6):1887-1894,doi:10.6038/cjg20130611.