Crustal structure of southeastern Tibetan Plateau inferred from double-difference tomography
-
摘要: 本文利用云南及周边区域地震台网2010—2016年记录到的近震资料，采用双差层析成像方法进行地震重定位并获得了青藏高原东南缘的三维地壳速度结构。结果显示：重定位后的震源位置精度得到明显提高，震源主要分布于20 km深度以上的中上地壳；地震分布与速度结构存在一定的相关性，大多数地震发生在中上地壳的低速异常区内以及高、低速异常区域之间；研究区上地壳速度结构存在明显的横向不均匀性，其速度异常与地表地形及地质特征密切相关；中下地壳分布着两条主要的低速带，一条沿着安宁河断裂、小江断裂分布在川滇菱形地块的东侧；另一条主要分布在川西北次级地块内，并穿过丽江断裂向南延伸，推测这两条低速带可能是青藏高原中下地壳物质向南逃逸的两条通道。Abstract: We applied the double-difference tomography to relocate seismic events and deter-mined the crustal structure of the southeastern Tibetan Plateau from the inversion of the local seismic data recorded by regional networks of Yunnan and its surrounding regions from 2010 to 2016. Our results demonstrate that the accuracy of events relocation is significantly improved, and the events are mainly distributed in upper-mid crust at the depths shallower than 20 km. The locations of events are closely related to the velocity structure of upper-mid crust. Most of the earthquakes occurred in some regions with low-velocity anomaly or in the regions between low-velocity and high-velocity anomalies. Tomography results also show that the velocity structure of upper crust exhibits apparent horizontal heterogeneities, which is largely consistent with surface geological and topographic features. In the mid-lower crust, there are two main NS-trending low-velocity zones, one is located in the east of Sichuan-Yunnan diamond block along the trace of Anninghe and Xiaojiang faults, and the other is mainly located in the northwestern Sichuan sub-block and extends to the south across the Lijiang fault. These low-velocity zones are deduced to be the two crustal channels for the southward escape of crustal matter in the middle and lower crust of Tibetan Plateau.
-
-
![]()
图 1 研究区域构造背景及台站分布
F1：怒江断裂；F2：澜沧江断裂；F3：南汀河断裂；F4：无量山断裂；F5：金沙江断裂；F6：红河断裂；F7：丽江断裂；F8：程海断裂；F9：绿汁江断裂；F10：安宁河断裂；F11：则木河断裂；F12：小江断裂
Figure 1. Regional tectonic settings and distribution of seismic stations in the studied area
F1：Nujiang fault；F2：Lancangjiang fault；F3：Nantinghe fault；F4：Wuliangshan fault；F5：Jinshajiang fault；F6：Honghe fault；F7：Lijiang fault；F8：Chenghai fault；F9：Lüzhijiang fault；F10：Anninghe fault；F11：Zemuhe fault；F12：Xiaojiang fault
![]()
图 4 利用L曲线法所选的最优平滑因子（a）和阻尼参数（b）
Figure 4. The optimum smoothing parameter （a） and damping parameter （b） selected by L curve method
![]()
图 6 重定位前（a）、后（b）的地震空间分布变化
Figure 6. Spatial variation of seismic events before （a） and after （b） relocation
![]()
图 7 重定位前（a）、后（b）的震源深度变化
Figure 7. Focal depth variation before （a） and after （b） relocation
![]()
图 8 不同深度h处P波速度扰动和地震分布图（粗实线AA′ ，BB′ ，CC′ 为地震剖面的位置）
Figure 8. P wave velocity disturbance and earthquake distribution at different depth h
The thick lines AA′ ，BB′ ，and CC′ represent the position of the seismic sections（a） h＝5 km；（b） h＝10 km；（c） h＝20 km；（d） h＝30 km；
![]()
表 1 P波初始速度模型
Table 1 Initial model of P wave velocity
深度/km vP/（km·s−1） 深度/km vP/（km·s−1） 0 5.50 20 6.23 5 5.89 30 6.50 10 6.02 40 6.90 
下载: 导出CSV
-
胡家富,苏有锦,朱雄关,陈赟. 2003. 云南的地壳S波速度与泊松比结构及其意义[J]. 中国科学:D辑,33(8):714–722. Hu J F,Su Y J,Zhu X G,Chen Y. 2005. S-wave velocity and Poisson’s ratio structure of crust in Yunnan and its implication[J]. Science in China:Series D,48(2):210–218. doi: 10.1360/03yd0062
黄金莉,赵大鹏,郑斯华. 2001. 川滇活动构造区地震层析成像[J]. 地球物理学报,44(增刊1):127–135. Huang J L,Zhao D P,Zheng S H. 2001. Seismic tomography of the Sichuan-Yunnan active tectonic region[J]. Chinese Journal of Geophysics,44(S1):127–135 (in Chinese).
李永华,吴庆举,田小波,张瑞青,潘佳铁,曾融生. 2009. 用接收函数方法研究云南及其邻区地壳上地幔结构[J]. 地球物理学报,52(1):67–80. Li Y H,Wu Q J,Tian X B,Zhang R Q,Pan J T,Zeng R S. 2009. Crustal structure in the Yunnan region determined by modeling receiver functions[J]. Chinese Journal of Geophysics,52(1):67–80 (in Chinese).
李永华,徐小明,张恩会,高家乙. 2014. 青藏高原东南缘地壳结构及云南鲁甸、景谷地震深部孕震环境[J]. 地震地质,36(4):1204–1216. doi: 10.3969/j.issn.0253-4967.2014.04.021 Li Y H,Xu X M,Zhang E H,Gao J Y. 2014. Three-dimensional crust structure beneath SE Tibetan Plateau and its seismotectonic implications for the Ludian and Jinggu earthquakes[J]. Seismology and Geology,36(4):1204–1216 (in Chinese).
潘佳铁,李永华,吴庆举,丁志峰. 2015. 青藏高原东南部地区瑞雷波相速度层析成像[J]. 地球物理学报,58(11):3993–4006. Pan J T,Li Y H,Wu Q J,Ding Z F. 2015. Phase velocity maps of Rayleigh waves in the southeast Tibetan Plateau[J]. Chinese Journal of Geophysics,58(11):3993–4006 (in Chinese). doi: 10.6038/cjg20151109
齐诚,赵大鹏,陈颙,陈棋福,王宝善. 2006. 首都圈地区地壳P波和S波三维速度结构及其与大地震的关系[J]. 地球物理学报,49(3):805–815. doi: 10.3321/j.issn:0001-5733.2006.03.024 Qi C,Zhao D P,Chen Y,Chen Q F,Wang B S. 2006. 3-D P and S wave velocity structures and their relationship to strong earthquakes in the Chinese capital region[J]. Chinese Journal of Geophysics,49(3):805–815 (in Chinese).
钱晓东,秦嘉政,刘丽芳. 2011. 云南地区现代构造应力场研究[J]. 地震地质,33(1):91–106. doi: 10.3969/j.issn.0253-4967.2011.01.009 Qian X D,Qin J Z,Liu L F. 2011. Study on recent tectonic stress field in Yunnan region[J]. Seismology and Geology,33(1):91–106 (in Chinese).
王椿镛,Mooney W D,王溪莉,吴建平,楼海,王飞. 2002. 川滇地区地壳上地幔三维速度结构研究[J]. 地震学报,24(1):1–16. doi: 10.3321/j.issn:0253-3782.2002.01.001 Wang C Y,Mooney W D,Wang X L,Wu J P,Lou H,Wang F. 2002. Study on 3-D velocity structure of crust and upper mantle in Sichuan-Yunnan region,China[J]. Acta Seismologica Sinica,24(1):1–16 (in Chinese).
王长在,吴建平,房立华,王未来. 2013. 玉树地震震源区速度结构与余震分布的关系[J]. 地球物理学报,56(12):4072–4083. doi: 10.6038/cjg20131212. Wang C Z,Wu J P,Fang L H,Wang W L. 2013. The relationship between wave velocity structure around Yushu earthquake source region and the distribution of aftershocks[J]. Chinese Journal of Geophysics,56(12):4072–4083 (in Chinese). doi: 10.6038/cjg20131212
王琼,高原. 2014. 青藏东南缘背景噪声的瑞利波相速度层析成像及强震活动[J]. 中国科学:地球科学,44(11):2440–2450. Wang Q,Gao Y. 2014. Rayleigh wave phase velocity tomography and strong earthquake activity on the southeastern front of the Tibetan Plateau[J]. Science China Earth Sciences,57(10):2532–2542. doi: 10.1007/s11430-014-4908-2
王琼,高原,石玉涛. 2015. 青藏高原东南缘基于背景噪声的Rayleigh面波方位各向异性研究[J]. 地球物理学报,58(11):4068–4078. Wang Q,Gao Y,Shi Y T. 2015. Rayleigh wave azimuthal anisotropy on the southeastern front of the Tibetan Plateau from seismic ambient noise[J]. Chinese Journal of Geophysics,58(11):4068–4078 (in Chinese). doi: 10.6038/cjg20151115
王小娜,于湘伟,章文波. 2015. 芦山震区地壳三维P波速度精细结构及地震重定位研究[J]. 地球物理学报,58(4):1179–1193. doi: 10.6038/cjg20150408. Wang X N,Yu X W,Zhang W B. 2015. 3D P-wave velocity structure of the crust and relocation of earthquakes in the Lushan source area[J]. Chinese Journal of Geophysics,58(4):1179–1193 (in Chinese). doi: 10.6038/cjg20150408
韦伟,孙若昧,石耀霖. 2010. 青藏高原东南缘地震层析成像及汶川地震成因探讨[J]. 中国科学:地球科学,40(7):831–839. Wei W,Sun R M,Shi Y L. 2010. P-wave tomographic images beneath southeastern Tibet:Investigating the mechanism of the 2008 Wenchuan earthquake[J]. Science China Earth Sciences,53(9):1252–1259. doi: 10.1007/s11430-010-4037-5
吴建平,明跃红,王椿镛. 2001. 云南数字地震台站下方的S波速度结构研究[J]. 地球物理学报,44(2):228–237. doi: 10.3321/j.issn:0001-5733.2001.02.010 Wu J P,Ming Y P,Wang C Y. 2001. The S wave velocity structure beneath digital seismic stations of Yunnan Province inferred from teleseismic receiver function modeling[J]. Chinese Journal of Geophysics,44(2):228–237 (in Chinese).
吴建平,杨婷,王未来,明跃红,张天中. 2013. 小江断裂带周边地区三维P波速度结构及其构造意义[J]. 地球物理学报,56(7):2257–2267. Wu J P,Yang T,Wang W L,Ming Y H,Zhang T Z. 2013. Three dimensional P-wave velocity structure around Xiaojiang fault system and its tectonic implications[J]. Chinese Journal of Geophysics,56(7):2257–2267 (in Chinese). doi: 10.6038/cjg20130713
肖卓,高原. 2017. 利用双差成像方法反演青藏高原东北缘及其邻区地壳速度结构[J]. 地球物理学报,60(6):2213–2225. doi: 10.6038/cjg20170615. Xiao Z,Gao Y. 2017. Crustal velocity structure beneath the northeastern Tibetan Plateau and adjacent regions derived from double difference tomography[J]. Chinese Journal of Geophysics,60(6):2213–2225 (in Chinese). doi: 10.6038/cjg20170615
熊绍柏,郑晔,尹周勋,曾晓献,全幼黎,孙克忠. 1993. 丽江—攀枝花—者海地带二维地壳结构及其构造意义[J]. 地球物理学报,36(4):434–444. doi: 10.3321/j.issn:0001-5733.1993.04.004 Xiong S B,Zheng Y,Yin Z X,Zeng X X,Quan Y L,Sun K Z. 1993. The 2-D structure and it’s implications of the crust in the Lijiang-Panzhihua-Zhehai region[J]. Chinese Journal of Geophysics,36(4):434–444 (in Chinese).
徐涛,张忠杰,刘宝峰,陈赟,张明辉,田小波,徐义刚,滕吉文. 2015. 峨眉山大火成岩省地壳速度结构与古地幔柱活动遗迹:来自丽江—清镇宽角地震资料的约束[J]. 中国科学:地球科学,45(5):561–576. Xu T,Zhang Z J,Liu B F,Chen Y,Zhang M H,Tian X B,Xu Y G,Teng J W. 2015. Crustal velocity structure in the Emeishan large igneous province and evidence of the Permian mantle plume activity[J]. Science China Earth Sciences,58(7):1133–1147. doi: 10.1007/s11430-015-5094-6
徐义刚,钟孙霖. 2001. 峨眉山大火成岩省:地幔柱活动的证据及其熔融条件[J]. 地球化学,30(1):1–9. doi: 10.3321/j.issn:0379-1726.2001.01.002 Xu Y G,Zhong S L. 2001. The Emeishan large igneous province:Evidence for mantle plume activity and melting conditions[J]. Geochimica,30(1):1–9 (in Chinese).
张培震. 2008. 青藏高原东缘川西地区的现今构造变形、应变分配与深部动力过程[J]. 中国科学:D辑,38(9):1041–1056. Zhang P Z. 2008. The present day tectonic deformation,strain partitioning and deep dynamic process of the western Sichuan region along eastern margin of Qinghai-Tibet Plateau[J]. Science in China:Series D,38(9):1041–1056 (in Chinese).
张招崇,Mahoney J J,王福生,赵莉,艾羽,杨铁铮. 2006. 峨眉山大火成岩省西部苦橄岩及其共生玄武岩的地球化学:地幔柱头部熔融的证据[J]. 岩石学报,22(6):1538–1552. doi: 10.3321/j.issn:1000-0569.2006.06.012 Zhang Z C,Mahoney J J,Wang F S,Zhao L,Ai Y,Yang T Z. 2006. Geochemistry of picritic and associated basalt flows of the western Emeishan flood basalt province,China:Evidence for a plume-head origin[J]. Acta Petrologica Sinica,22(6):1538–1552 (in Chinese).
郑晨,丁志峰,宋晓东. 2016. 利用面波频散与接收函数联合反演青藏高原东南缘地壳上地幔速度结构[J]. 地球物理学报,59(9):3223–3236. doi: 10.6038/cjg20160908. Zheng C,Ding Z F,Song X D. 2016. Joint inversion of surface wave dispersion and receiver functions for crustal and uppermost mantle structure in southeast Tibetan Plateau[J]. Chinese Journal of Geophysics,59(9):3223–3236 (in Chinese). doi: 10.6038/cjg20160908
郑定昌,盖增喜,杨润海,闵照旭,唐有彩,姜明明,庞卫东. 2014. 云南地区背景噪声层析成像[J]. 地震学报,36(4):602–614. doi: 10.3969/j.issn.0253-3782.2014.04.007 Zheng D C,Ge Z X,Yang R H,Min Z X,Tang Y C,Jiang M M,Pang W D. 2014. Broadband ambient noise tomography in Yunnan Province[J]. Acta Seismologica Sinica,36(4):602–614 (in Chinese). doi: 10.3969/j.issn.0253-3782.2014.04.007
周龙泉,刘杰,苏有锦,马宏生,周俊杰. 2009. 利用S波高频衰减参数对云南地区地壳Q值成像[J]. 地球物理学报,52(6):1500–1507. doi: 10.3969/j.issn.0001-5733.2009.06.011 Zhou L Q,Liu J,Su Y J,Ma H S,Zhou J J. 2009. Tomography for Q of Yunnan region from high-frequency attenuation of S wave[J]. Chinese Journal of Geophysics,52(6):1500–1507 (in Chinese).
Avouac J P,Tapponnier P. 1993. Kinematic model of active deformation in central Asia[J]. Geophys Res Lett,20(10):895–898. doi: 10.1029/93GL00128
Bai D H,Unsworth M J,Meju M A,Ma X B,Teng J W,Kong X R,Sun Y,Sun J,Wang L F,Jiang C S,Zhao C P,Xiao P F,Liu M. 2010. Crustal deformation of the eastern Tibetan Plateau revealed by magnetotelluric imaging[J]. Nat Geosci,3(5):358–362. doi: 10.1038/ngeo830
Bao X W,Sun X X,Xu M J,Eaton D W,Song X D,Wang L S,Ding Z F,Mi N,Li H,Yu D Y,Huang Z C,Wang P. 2015. Two crustal low-velocity channels beneath SE Tibet revealed by joint inversion of Rayleigh wave dispersion and receiver functions[J]. Earth Planet Sci Lett,415:16–24. doi: 10.1016/j.jpgl.2015.01.020
Clark M K,Royden L H. 2000. Topographic ooze:Building the eastern margin of Tibet by lower crustal flow[J]. Geology,28(8):703–706. doi: 10.1130/0091-7613(2000)28<703:TOBTEM>2.0.CO;2
Eberhart-Phillips D. 1986. Three-dimensional velocity structure in northern California Coast Ranges from inversion of local earthquake arrival times[J]. Bull Seismol Soc Am,76(4):1025–1052.
He B,Xu Y G,Chung S L,Xiao L,Wang Y M. 2003. Sedimentary evidence for a rapid,kilometer-scale crustal doming prior to the eruption of the Emeishan flood basalts[J]. Earth Planet Sci Lett,213(3/4):391–405.
Hu S B,He L J,Wang J Y. 2000. Heat flow in the continental area of China:A new data set[J]. Earth Planet Sci Lett,179(2):407–419. doi: 10.1016/S0012-821X(00)00126-6
Huang J L,Zhao D P,Zheng S H. 2002. Lithospheric structure and its relationship to seismic and volcanic activity in southwest China[J]. J Geophys Res,107(B10):ESE 13-1–ESE 13-14. doi: 10.1029/2000JB000137
Leloup P H,Ricard Y,Battaglia J,Lacassin R. 1999. Shear heating in continental strike-slip shear zones:Model and field examples[J]. Geophys J Int,136(1):19–40. doi: 10.1046/j.1365-246X.1999.00683.x
Li M K,Zhang S X,Wang F,Wu T F,Qin W B. 2016. Crustal and upper-mantle structure of the southeastern Tibetan Plateau from joint analysis of surface wave dispersion and receiver functions[J]. J Asian Earth Sci,117(9):52–63.
Liu Q Y,van der Hilst R D,Li Y,Yao H J,Chen J H,Guo B,Qi S H,Wang J,Huang H,Li S C. 2014. Eastward expansion of the Tibetan Plateau by crustal flow and strain partitioning across faults[J]. Nat Geosci,7(5):361–365. doi: 10.1038/ngeo2130
Royden L H,Burchfiel B C,King R W,Wang E,Chen Z L,Shen F,Liu Y P. 1997. Surface deformation and lower crustal flow in eastern Tibet[J]. Science,276(5313):788–790. doi: 10.1126/science.276.5313.788
Spakman W,van der Lee S,van der Hilst R. 1993. Travel-time tomography of the European-Mediterranean mantle down to 1 400 km[J]. Phys Earth Planet Inter,79(1/2):3–74. doi: 10.1016/0031-9201（93）90142-V.
Sun X X,Bao X W,Xu M J,Eaton D W,Song X D,Wang L S,Ding Z F,Mi N,Yu D Y,Li H. 2014. Crustal structure beneath SE Tibet from joint analysis of receiver functions and Rayleigh wave dispersion[J]. Geophys Res Lett,41(5):1479–1484. doi: 10.1002/2014GL059269
Tapponnier P,Molnar P. 1976. Slip-line field theory and large-scale continental tectonics[J]. Nature,264(5584):319–324. doi: 10.1038/264319a0
Tapponnier P,Peltzer G,Le Dain A Y,Armijo R,Cobbold P. 1982. Propagating extrusion tectonics in Asia:New insights from simple experiments with plasticine[J]. Geology,10(12):611–616. doi: 10.1130/0091-7613(1982)10<611:PETIAN>2.0.CO;2
Waldhauser F,Ellsworth W L. 2000. A double-difference earthquake location algorithm:Method and application to the northern Hayward fault,California[J]. Bull Seismol Soc Am,90(6):1353–1368. doi: 10.1785/0120000006
Yao H J,Beghein C,van der Hilst R D. 2008. Surface wave array tomography in SE Tibet from ambient seismic noise and two-station analysis:II. Crustal and upper-mantle structure[J]. Geophys J Int,173(1):205–219. doi: 10.1111/gji.2008.173.issue-1
Yin A,Harrison T M. 2000. Geologic evolution of the Himalayan-Tibetan orogen[J]. Ann Rev Earth Planet Sci,28:211–280. doi: 10.1146/annurev.earth.28.1.211
Zhang H J,Thurber C H. 2003. Double-difference tomography:The method and its application to the Hayward fault,California[J]. Bull Seismol Soc Am,93(5):1875–1889. doi: 10.1785/0120020190.
Zhang H J,Thurber C H. 2006. Development and applications of double-difference seismic tomography[J]. Pure Appl Geophys,163(2/3):373–403. doi: 10.1007/s00024-005-0021-y.
Zhang X,Wang Y H. 2009. Crustal and upper mantle velocity structure in Yunnan,Southwest China[J]. Tectonophysics,471(3/4):171–185.
Zhao D P,Kanamori H,Negishi H,Wiens D. 1996. Tomography of the source area of the 1995 Kobe earthquake:Evidence for fluids at the hypocenter?[J]. Science,274(5294):1891–1894. doi: 10.1126/science.274.5294.1891
Zhao D P,Ochi F,Hasegawa A,Yamamoto A. 2000. Evidence for the location and cause of large crustal earthquakes in Japan[J]. J Geophys Res,105(B6):13579–13594. doi: 10.1029/2000JB900026
Zhao L F,Xie X B,He J K,Tian X B,Yao Z X. 2013. Crustal flow pattern beneath the Tibetan Plateau constrained by regional Lg-wave Q tomography[J]. Earth Planet Sci Lett,383(4):113–122.
-
期刊类型引用(4)
1. 陈长龙，刘启方. 三种非线性时变识别方法的对比研究——以2021年日本福岛地震为例. 地震工程学报. 2023(02): 372-381 . 
百度学术
2. 吴双兰，野津厚，長坂陽介. 2021年日本福岛县冲地震的震源破裂过程分析——基于采用经验格林函数方法的波形反演. 世界地震工程. 2021(02): 1-12 . 百度学术
3. 徐志国，梁姗姗，张广伟，梁建宏，邹立晔，李旭茂，陈彦含. 2021年5月22日青海玛多M_S7.4地震发震构造分析. 地球物理学报. 2021(08): 2657-2670 . 百度学术
4. 张喆，许力生. 2021年青海玛多M_W7.5地震矩心矩张量解. 地震学报. 2021(03): 387-391 . 本站查看
其他类型引用(1)
计量
- 文章访问数: 2408
- HTML全文浏览量: 1611
- PDF下载量: 252
- 被引次数: 5
