利用区域地震体波走时评价华北地区三维地壳速度结构模型
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摘要
本研究利用国家地震台网131个地震台站2009—2016年记录的1 749次近震的初至P波和S波走时数据,与采用快速行进方法正演计算得到的华北地区4个三维地壳速度模型对应的走时数据进行对比,通过统计分析的方法,评价这4个速度模型与真实地下结构的近似程度。结果表明:4个速度模型在大范围内存在较高的一致性,在整个研究区内(111°E—119.5°E,37°N—42°N),Shen等的模型(简称"S模型")相对优于Fang等的模型(简称"F模型")和Duan等的模型(简称"D模型"),Laske等的Crust1.0模型(简称"C模型")相对较差。我们认为该结果与上述几个模型所使用的数据及其分辨率有关。对于研究区域内的构造单元,D模型在燕山褶皱带西南部、太行山山前构造带西北部和沧县隆起区表现较好,F模型在太行山隆起区中部、沧县隆起北部、黄骅凹陷区和燕山褶皱带表现较好,S模型在西部地块、山西凹陷区、太行山山前构造带和冀中凹陷区表现较好,C模型无明显连片表现较好区域。
Due to the differences in research methods and data,there may exist multiple velocity models in the same area,but the reliability of these models usually lacks systematic and objective assessment. In this study we compare the observed first arrival time data of P-wave and S-wave of 1 749 earthquakes from 2009 to 2016,which were recorded by 131 seismograph stations of the National Seismological Network in North China,with the predicted travel time data from four 3D crustal velocity models in North China using the fast marching method.Then,using statistical analysis we evaluate the relative merits of these four models with respect to the real underground structures. The results reveal that the large-scale pattern generally shows consistency for these four models. Within the entire studied area,the model proposed by Shen et al(referred to as "S model") is relatively better than the model proposed by Fang et al(referred to as "F model") and Duan et al(referred to as "D model"). The Crust 1.0 model(referred to as "C model") is relatively worse. We think that the reasons for this result are related to the differences in data used in model construction and the associated resolution. For different tectonic units in the studied area,the D model performs better in the southwestern part of the Yanshan folded belt,northwestern part of the Taihang mountain foreland tectonic belt,and the Cangxian uplift area. The F model performs better in the central part of Taihang mountain uplift,northern part of the Cangxian uplifted area,the Huanghua depression,and the Yanshan fold belt. The S model appears better in the western block,the Shanxi depression area,the Taihang mountain foreland tectonic belt,and the Jizhong depression area. There is no obvious large continuous area where the C model performs better. Our study has certain positive significance for further accuracy improvement of the regional crustal velocity models and the earthquake location study based on 3D models.
Due to the differences in research methods and data,there may exist multiple velocity models in the same area,but the reliability of these models usually lacks systematic and objective assessment. In this study we compare the observed first arrival time data of P-wave and S-wave of 1 749 earthquakes from 2009 to 2016,which were recorded by 131 seismograph stations of the National Seismological Network in North China,with the predicted travel time data from four 3D crustal velocity models in North China using the fast marching method.Then,using statistical analysis we evaluate the relative merits of these four models with respect to the real underground structures. The results reveal that the large-scale pattern generally shows consistency for these four models. Within the entire studied area,the model proposed by Shen et al(referred to as "S model") is relatively better than the model proposed by Fang et al(referred to as "F model") and Duan et al(referred to as "D model"). The Crust 1.0 model(referred to as "C model") is relatively worse. We think that the reasons for this result are related to the differences in data used in model construction and the associated resolution. For different tectonic units in the studied area,the D model performs better in the southwestern part of the Yanshan folded belt,northwestern part of the Taihang mountain foreland tectonic belt,and the Cangxian uplift area. The F model performs better in the central part of Taihang mountain uplift,northern part of the Cangxian uplifted area,the Huanghua depression,and the Yanshan fold belt. The S model appears better in the western block,the Shanxi depression area,the Taihang mountain foreland tectonic belt,and the Jizhong depression area. There is no obvious large continuous area where the C model performs better. Our study has certain positive significance for further accuracy improvement of the regional crustal velocity models and the earthquake location study based on 3D models.
引文
陈国英,宋仲和,安昌强,陈立华,庄真,傅竹武,吕梓龄,胡家富.1991.华北地区三维地壳上地幔结构[J].地球物理学报,34(2):172-181.Chen G Y,Song Z H,An C Q,Chen L H,Zhuang Z,Fu Z W,LüZ L,Hu J F.1991.Three-dimensional crust and upper mantle structure of the North China region[J].Acta Geophysica Sinica,34(2):172-181(in Chinese).
陈凌,程骋,危自根.2010.华北克拉通边界带区域深部结构的特征差异性及其构造意义[J].地球科学进展,25(6):571-581.Chen L,Cheng C,Wei Z G.2010.Contrasting structural features at different boundary areas of the North China Craton and its tectonic implications[J].Advances in Earth Science,25(6):571-581(in Chinese).
陈立华,宋仲和.1990.华北地区地壳上地幔P波速度结构[J].地球物理学报,33(5):540-546.Chen L H,Song Z H.1990.Crust-upper mantle P wave velocity structure beneath northern China[J].Acta Geophysica Sinica,33(5):540-546(in Chinese).
陈兆辉,楼海,孟小红,王椿镛,石磊.2014.鄂尔多斯块体-华北地区地壳上地幔P波三维速度结构[J].地球物理学进展,29(3):999-1007.Chen Z H,Lou H,Meng X H,Wang C Y,Shi L.2014.3D P-wave velocity structure of crust and upper mantle beneath Ordos Block and North China[J].Progress in Geophysics,29(3):999-1007(in Chinese).
丁志峰,何正勤,孙为国,孙宏川.1999.青藏高原东部及其边缘地区的地壳上地幔三维速度结构[J].地球物理学报,42(2):197-205.Ding Z F,He Z Q,Sun W G,Sun H C.1999.3-D crust and upper mantle velocity structure in eastern Tibetan Plateau and its surrounding areas[J].Chinese Journal of Geophysics,42(2):197-205(in Chinese).
嵇少丞,王茜,许志琴.2008.华北克拉通破坏与岩石圈减薄[J].地质学报,82(2):174-193.Ji S C,Wang Q,Xu Z Q.2008.Break-up of the North China Craton through lithospheric thinning[J].Acta Geologica Sinica,82(2):174-193(in Chinese).
嘉世旭,张先康,方盛明.2001.华北裂陷盆地不同块体地壳结构及演化研究[J].地学前缘,8(2):259-266.Jia S X,Zhang X K,Fang S M.2001.Research on the crustal structure and evolution of different blocks in North China riftdepression basin[J].Earth Science Frontiers,8(2):259-266(in Chinese).
金安蜀,刘福田,孙永智.1980.北京地区地壳和上地幔的三维P波速度结构[J].地球物理学报,23(2):172-182.Jin A S,Liu F T,Sun Y Z.1980.Three-dimensional P velocity structure of the crust and upper mantle under Beijing region[J].Acta Geophysica Sinica,23(2):172-182(in Chinese).
赖锡安,黄立人,徐菊生.2004.中国大陆现今地壳运动[M].北京:地震出版社:29-31.Lai X A,Huang L R,Xu J S.2004.Present-Day Crustal Movement in China Continent[M].Beijing:Seismological Press:29-31(in Chinese).
李志伟,胥颐,郝天珧,刘劲松,张岭.2006.环渤海地区的地震层析成像与地壳上地幔结构[J].地球物理学报,49(3):797-804.Li Z W,Xu Y,Hao T Y,Liu J S,Zhang L.2006.Seismic tomography and velocity structure in the crust and upper mantle around Bohai Sea area[J].Chinese Journal of Geophysics,49(3):797-804(in Chinese).
刘福田,曲克信,吴华,李强,刘建华,胡戈.1986.华北地区的地震层面成象[J].地球物理学报,29(5):442-449.Liu F T,Qu K X,Wu H,Li Q,Liu J H,Hu G.1986.Seismic tomography of North China region[J].Acta Geophysica Sinica,29(5):442-449(in Chinese).
刘启元,李顺成,沈扬,陈九辉.1997.延怀盆地及其邻区地壳上地幔速度结构的宽频带地震台阵研究[J].地球物理学报,40(6):763-772.Liu Q Y,Li S C,Shen Y,Chen J H.1997.Broadband seismic array study of the crust and upper mantle velocity structure beneath Yanhuai basin and its neighbouring region[J].Acta Geophysica Sinica,40(6):763-772(in Chinese).
吕作勇,吴建平.2010.华北地区地壳上地幔三维P波速度结构[J].地震学报,32(1):1-11.LüZ Y,Wu J P.2010.3-D P wave velocity structure of crust and upper mantle beneath North China[J].Acta Seismologica Sinica,32(1):1-11(in Chinese).
马杏垣,刘和甫,王维襄,汪一鹏.1983.中国东部中、新生代裂陷作用和伸展构造[J].地质学报,57(1):22-32.Ma X Y,Liu H F,Wang W X,Wang Y P.1983.Meso-Cenozoic taphrogeny and extensional tectonics in eastern China[J].Acta Geologica Sinica,57(1):22-32(in Chinese).
魏文博,叶高峰,金胜,邓明,景建恩.2007.华北地区地壳P波三维速度结构[J].地球科学:中国地质大学学报,32(4):441-452.Wei W B,Ye G F,Jin S,Deng M,Jing J E.2007.Three dimensional P-wave velocity structure of the crust of North China[J].Earth Science:Journal of China University of Geosciences,32(4):441-452(in Chinese).
吴福元,徐义刚,高山,郑建平.2008.华北岩石圈减薄与克拉通破坏研究的主要学术争论[J].岩石学报,24(6):1145-1174.Wu F Y,Xu Y G,Gao S,Zheng J P.2008.Lithospheric thinning and destruction of the North China Craton[J].Acta Petrologica Sinica,24(6):1145-1174(in Chinese).
徐伟进,高孟潭.2014.中国大陆及周缘地震目录完整性统计分析[J].地球物理学报,57(9):2802-2812.Xu W J,Gao M T.2014.Statistical analysis of the completeness of earthquake catalogs in China mainland[J].Chinese Journal of Geophysics,57(9):2802-2812(in Chinese).
杨婷,吴建平,房立华,王未来,吕作勇.2012.华北地区地壳上地幔S波三维速度结构[J].地球物理学进展,27(2):441-454.Yang T,Wu J P,Fang L H,Wang W L,LüZ Y.2012.3-D S-wave velocity structure of crust and upper mantle beneath North China[J].Progress in Geophysics,27(2):441-454(in Chinese).
朱日祥,徐义刚,朱光,张宏福,夏群科,郑天愉.2012.华北克拉通破坏[J].中国科学:地球科学,42(8):1135-1159.Zhu R X,Xu Y G,Zhu G,Zhang H F,Xia Q K,Zheng T Y.2012.Destruction of the North China Craton[J].Science China Earth Sciences,55(10):1565-1587.
Brocher T M.2005.Empirical relations between elastic wave speeds and density in the Earth’s crust[J].Bull Seismol Soc Am,95(6):2081-2092.
Duan Y H,Wang F Y,Zhang X K,Lin J Y,Liu Z,Liu B F,Yang Z X,Guo W B,Wei Y H.2016.Three-dimensional crustal velocity structure model of the middle-eastern North China Craton(HBCrust1.0)[J].Science China Earth Sciences,59(7):1477-1488.
Fang L H,Wu J P,Ding Z F,Wang W L,Panza G F.2010.Crustal velocity structures beneath North China revealed by ambient noise tomography[J].Earthquake Science,23(5):477-486.
Laske G,Masters G,Ma Z T,Pasyanos M.2013.Update on Crust1.0:A 1-degree global model of Earth’s crust[C]//EGU General Assembly Conference Abstracts.Vienna,Austria:EGU,15:2658.
Liu D Y,Nutman A P,Compston W,Wu J S,Shen Q H.1992.Remnants of≥3800 Ma crust in the Chinese part of the SinoKorean Craton[J].Geology,20(4):339-342.
Rawlinson N,Sambridge M.2005.The fast marching method:An effective tool for tomographic imaging and tracking multiple phases in complex layered media[J].Explor Geophys,36(4):341-350.
Shen W S,Ritzwoller M H,Kang D,Kim Y,Lin F C,Ning J Y,Wang W T,Zheng Y,Zhou L Q.2016.A seismic reference model for the crust and uppermost mantle beneath China from surface wave dispersion[J].Geophys J Int,206(2):954-979.
Zhao G C,Wilde S A,Cawood P A,Sun M.2001.Archean blocks and their boundaries in the North China Craton:Lithological,geochemical,structural and P-T path constraints and tectonic evolution[J].Precambrian Res,107(1/2):45-73.
陈凌,程骋,危自根.2010.华北克拉通边界带区域深部结构的特征差异性及其构造意义[J].地球科学进展,25(6):571-581.Chen L,Cheng C,Wei Z G.2010.Contrasting structural features at different boundary areas of the North China Craton and its tectonic implications[J].Advances in Earth Science,25(6):571-581(in Chinese).
陈立华,宋仲和.1990.华北地区地壳上地幔P波速度结构[J].地球物理学报,33(5):540-546.Chen L H,Song Z H.1990.Crust-upper mantle P wave velocity structure beneath northern China[J].Acta Geophysica Sinica,33(5):540-546(in Chinese).
陈兆辉,楼海,孟小红,王椿镛,石磊.2014.鄂尔多斯块体-华北地区地壳上地幔P波三维速度结构[J].地球物理学进展,29(3):999-1007.Chen Z H,Lou H,Meng X H,Wang C Y,Shi L.2014.3D P-wave velocity structure of crust and upper mantle beneath Ordos Block and North China[J].Progress in Geophysics,29(3):999-1007(in Chinese).
丁志峰,何正勤,孙为国,孙宏川.1999.青藏高原东部及其边缘地区的地壳上地幔三维速度结构[J].地球物理学报,42(2):197-205.Ding Z F,He Z Q,Sun W G,Sun H C.1999.3-D crust and upper mantle velocity structure in eastern Tibetan Plateau and its surrounding areas[J].Chinese Journal of Geophysics,42(2):197-205(in Chinese).
嵇少丞,王茜,许志琴.2008.华北克拉通破坏与岩石圈减薄[J].地质学报,82(2):174-193.Ji S C,Wang Q,Xu Z Q.2008.Break-up of the North China Craton through lithospheric thinning[J].Acta Geologica Sinica,82(2):174-193(in Chinese).
嘉世旭,张先康,方盛明.2001.华北裂陷盆地不同块体地壳结构及演化研究[J].地学前缘,8(2):259-266.Jia S X,Zhang X K,Fang S M.2001.Research on the crustal structure and evolution of different blocks in North China riftdepression basin[J].Earth Science Frontiers,8(2):259-266(in Chinese).
金安蜀,刘福田,孙永智.1980.北京地区地壳和上地幔的三维P波速度结构[J].地球物理学报,23(2):172-182.Jin A S,Liu F T,Sun Y Z.1980.Three-dimensional P velocity structure of the crust and upper mantle under Beijing region[J].Acta Geophysica Sinica,23(2):172-182(in Chinese).
赖锡安,黄立人,徐菊生.2004.中国大陆现今地壳运动[M].北京:地震出版社:29-31.Lai X A,Huang L R,Xu J S.2004.Present-Day Crustal Movement in China Continent[M].Beijing:Seismological Press:29-31(in Chinese).
李志伟,胥颐,郝天珧,刘劲松,张岭.2006.环渤海地区的地震层析成像与地壳上地幔结构[J].地球物理学报,49(3):797-804.Li Z W,Xu Y,Hao T Y,Liu J S,Zhang L.2006.Seismic tomography and velocity structure in the crust and upper mantle around Bohai Sea area[J].Chinese Journal of Geophysics,49(3):797-804(in Chinese).
刘福田,曲克信,吴华,李强,刘建华,胡戈.1986.华北地区的地震层面成象[J].地球物理学报,29(5):442-449.Liu F T,Qu K X,Wu H,Li Q,Liu J H,Hu G.1986.Seismic tomography of North China region[J].Acta Geophysica Sinica,29(5):442-449(in Chinese).
刘启元,李顺成,沈扬,陈九辉.1997.延怀盆地及其邻区地壳上地幔速度结构的宽频带地震台阵研究[J].地球物理学报,40(6):763-772.Liu Q Y,Li S C,Shen Y,Chen J H.1997.Broadband seismic array study of the crust and upper mantle velocity structure beneath Yanhuai basin and its neighbouring region[J].Acta Geophysica Sinica,40(6):763-772(in Chinese).
吕作勇,吴建平.2010.华北地区地壳上地幔三维P波速度结构[J].地震学报,32(1):1-11.LüZ Y,Wu J P.2010.3-D P wave velocity structure of crust and upper mantle beneath North China[J].Acta Seismologica Sinica,32(1):1-11(in Chinese).
马杏垣,刘和甫,王维襄,汪一鹏.1983.中国东部中、新生代裂陷作用和伸展构造[J].地质学报,57(1):22-32.Ma X Y,Liu H F,Wang W X,Wang Y P.1983.Meso-Cenozoic taphrogeny and extensional tectonics in eastern China[J].Acta Geologica Sinica,57(1):22-32(in Chinese).
魏文博,叶高峰,金胜,邓明,景建恩.2007.华北地区地壳P波三维速度结构[J].地球科学:中国地质大学学报,32(4):441-452.Wei W B,Ye G F,Jin S,Deng M,Jing J E.2007.Three dimensional P-wave velocity structure of the crust of North China[J].Earth Science:Journal of China University of Geosciences,32(4):441-452(in Chinese).
吴福元,徐义刚,高山,郑建平.2008.华北岩石圈减薄与克拉通破坏研究的主要学术争论[J].岩石学报,24(6):1145-1174.Wu F Y,Xu Y G,Gao S,Zheng J P.2008.Lithospheric thinning and destruction of the North China Craton[J].Acta Petrologica Sinica,24(6):1145-1174(in Chinese).
徐伟进,高孟潭.2014.中国大陆及周缘地震目录完整性统计分析[J].地球物理学报,57(9):2802-2812.Xu W J,Gao M T.2014.Statistical analysis of the completeness of earthquake catalogs in China mainland[J].Chinese Journal of Geophysics,57(9):2802-2812(in Chinese).
杨婷,吴建平,房立华,王未来,吕作勇.2012.华北地区地壳上地幔S波三维速度结构[J].地球物理学进展,27(2):441-454.Yang T,Wu J P,Fang L H,Wang W L,LüZ Y.2012.3-D S-wave velocity structure of crust and upper mantle beneath North China[J].Progress in Geophysics,27(2):441-454(in Chinese).
朱日祥,徐义刚,朱光,张宏福,夏群科,郑天愉.2012.华北克拉通破坏[J].中国科学:地球科学,42(8):1135-1159.Zhu R X,Xu Y G,Zhu G,Zhang H F,Xia Q K,Zheng T Y.2012.Destruction of the North China Craton[J].Science China Earth Sciences,55(10):1565-1587.
Brocher T M.2005.Empirical relations between elastic wave speeds and density in the Earth’s crust[J].Bull Seismol Soc Am,95(6):2081-2092.
Duan Y H,Wang F Y,Zhang X K,Lin J Y,Liu Z,Liu B F,Yang Z X,Guo W B,Wei Y H.2016.Three-dimensional crustal velocity structure model of the middle-eastern North China Craton(HBCrust1.0)[J].Science China Earth Sciences,59(7):1477-1488.
Fang L H,Wu J P,Ding Z F,Wang W L,Panza G F.2010.Crustal velocity structures beneath North China revealed by ambient noise tomography[J].Earthquake Science,23(5):477-486.
Laske G,Masters G,Ma Z T,Pasyanos M.2013.Update on Crust1.0:A 1-degree global model of Earth’s crust[C]//EGU General Assembly Conference Abstracts.Vienna,Austria:EGU,15:2658.
Liu D Y,Nutman A P,Compston W,Wu J S,Shen Q H.1992.Remnants of≥3800 Ma crust in the Chinese part of the SinoKorean Craton[J].Geology,20(4):339-342.
Rawlinson N,Sambridge M.2005.The fast marching method:An effective tool for tomographic imaging and tracking multiple phases in complex layered media[J].Explor Geophys,36(4):341-350.
Shen W S,Ritzwoller M H,Kang D,Kim Y,Lin F C,Ning J Y,Wang W T,Zheng Y,Zhou L Q.2016.A seismic reference model for the crust and uppermost mantle beneath China from surface wave dispersion[J].Geophys J Int,206(2):954-979.
Zhao G C,Wilde S A,Cawood P A,Sun M.2001.Archean blocks and their boundaries in the North China Craton:Lithological,geochemical,structural and P-T path constraints and tectonic evolution[J].Precambrian Res,107(1/2):45-73.