Advanced Search

EPP

地球与行星物理

ISSN  2096-3955

CN  10-1502/P

Citation: JianHui Tian, Yan Luo, Li Zhao, 2019: Regional stress field in Yunnan revealed by the focal mechanisms of moderate and small earthquakes, Earth and Planetary Physics, 3, 243-252. http://doi.org/10.26464/epp2019024

2019, 3(3): 243-252. doi: 10.26464/epp2019024

SOLID EARTH: TECTONOPHYSICS

Regional stress field in Yunnan revealed by the focal mechanisms of moderate and small earthquakes

1. 

Key Laboratory of Earthquake Prediction, Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China

2. 

School of Earth and Space Sciences, Peking University, Beijing 100871, China

Corresponding author: Li Zhao, lizhaopku@pku.edu.cn

Received Date: 2019-01-29
Web Publishing Date: 2019-04-02

We determined focal mechanism solutions of 627 earthquakes of magnitude M ≥ 3.0 in Yunnan from January 2008 to May 2018 by using broadband waveforms recorded by 287 permanent and temporary regional stations. The results clearly revealed predominantly strike-slip faulting characteristics for earthquakes in Yunnan, with focal depths concentrated in the top 10 km of the crust. The earthquake mechanisms obtained were combined with the global centroid moment tensor solutions of 80 additional earthquakes from 1976 to 2016 to invert for the regional variations of stress field orientation by using a damped regional-scale stress inversion scheme. Results of the stress field inversion confirmed that the Yunnan region is under a strike–slip stress regime, with both maximum and minimum stress axes being nearly horizontal. The maximum compressional axes are primarily oriented in a northwest-southeast direction, and they experience a clockwise rotation from north to south, whereas the maximum extensional axes are oriented largely northeast-southwest. The maximum compressional axes are in line with the global positioning system–inferred horizontal velocity field and the southeastward escape of the Sichuan–Yunnan Rhombic Block, whereas the maximum extensional axes are consistent with anisotropy derived from SKS splitting. Against the strike–slip background, normal faulting stress regimes can be seen in the Tengchong volcanic area as well as in other areas with complex crisscrossing fault zones.

Key words: earthquake focal mechanism, stress field inversion, principle stresses, Yunnan region

Angelier, J. (1979). Determination of the mean principal directions of stresses for a given fault population. Tectonophysics, 56(3-4), T17–T26. https://doi.org/10.1016/0040-1951(79)90081-7

Angelier, J. (1984). Tectonic analysis of fault slip data sets. J. Geophys. Res. Solid Earth, 89(B7), 5835–5848. https://doi.org/10.1029/JB089iB07p05835

Gephart, J. W., and Forsyth, D. W. (1984). An improved method for determining the regional stress tensor using earthquake focal mechanism data: Application to the San Fernando earthquake sequence. J. Geophys. Res. Solid Earth, 89(B11), 9305–9320. https://doi.org/10.1029/JB089iB11p09305

Hardebeck, J. L., and Hauksson, E. (2001). Crustal stress field in southern California and its implications for fault mechanics. J. Geophys. Res. Solid Earth, 106(B10), 21859–21882. https://doi.org/10.1029/2001JB000292

Hardebeck, J. L., and Michael, A. J. (2006). Damped regional-scale stress inversions: Methodology and examples for southern California and the Coalinga aftershock sequence. J. Geophys. Res. Solid Earth, 111(B11), B11310. https://doi.org/10.1029/2005JB004144

Hu, H. X., and Gao, S. Y. (1993). The investigation of fine velocity structure of the basement layer of earth’s crust in western Yunnan region. Earthq. Res. China (in Chinese) , 9(4), 354–363.

Huang, F. G., Chen, Y., Qin, J. Z., Li, Z. H., An, X. W., and Yang, Z. S. (2010). The Seismicity in Yunnan (in Chinese). Kunming: Yunnan Science and Technology Press.222

Lü, J., Zheng, Y., Ni, S. D., and Gao, J. H. (2008). Focal mechanisms and seismogenic structures of the Ms5.7 and Ms4.8 Jiujiang-Ruichang earthquakes of Nov. 26, 2005. Chinese J. Geophys. (in Chinese) , 51(1), 158–164. https://doi.org/10.3321/j.issn:0001-5733.2008.01.020

Long, F., Zhang, Y. J., Wen, X. Z., Ni, S. D., and Zhang, Z. W. (2010). Focal mechanism solutions of ML≥4.0 events in the Ms6.1 Panzhihua-Huili earthquake sequence of Aug 30, 2008. Chinese J. Geophys. (in Chinese) , 53(12), 2852–2860. https://doi.org/10.3969/j.issn.0001-5733.2010.12.008

Luo, J., Zhao, C. P., Lü, J., Zhou, L. Q., and Zheng, S. H. (2016). Characteristics of focal mechanisms and the stress field in the Southeastern Margin of the Tibetan Plateau. Pure Appl. Geophys., 173(8), 2687–2710. https://doi.org/10.1007/s00024-016-1350-8

Luo, Y., Ni, S. D., Zeng, X. F., Zhen, Y., Chen, Q. F., and Chen, Y. (2010). A shallow aftershock sequence in the north-eastern end of the Wenchuan earthquake aftershock zone. Sci. China Earth Sci., 53(11), 1655–1664. https://doi.org/10.1007/s11430-010-4026-8

McKenzie, D. P. (1969). The relation between fault plane solutions for earthquakes and the directions of the principal stresses. Bull. Seismol. Soc. Am., 59(2), 591–601.

Michael, A. J. (1984). Determination of stress from slip data: Faults and folds. J. Geophys. Res. Solid Earth, 89(B13), 11517–11526. https://doi.org/10.1029/JB089iB13p11517

Michael, A. J. (1987). Use of focal mechanisms to determine stress: A control study. J. Geophys. Res. Solid Earth, 92(B1), 357–368. https://doi.org/10.1029/JB092iB01p00357

Qian, X. D., Qin, J. Z., and Liu, L. F. (2011). Study on recent tectonic stress field in Yunnan region. Seismol. Geol. (in Chinese) , 33(1), 91–106. https://doi.org/10.3969/j.issn.0253-4967.2011.01.009

Qiao, X. J., Wang, Q., and Du, R. L. (2004). Characteristics of current crustal deformation of active blocks in the Sichuan-Yunnan region. Chinese J. Geophys. (in Chinese) , 47(5), 805–811. https://doi.org/10.3321/j.issn:0001-5733.2004.05.011

Shen, C. Y., Wu, Y., Wang, Q., You, X. Z., and Qiao, X. J. (2002). GPS data inversion of kinematic model of main faults in Yunnan. J. Geodesy Geodyn. (in Chinese) , 22(3), 46–51. https://doi.org/10.3969/j.issn.1671-5942.2002.03.009

Shi, Y. T., Gao, Y., Su, Y. J., and Wang, Q. (2012). Shear-wave splitting beneath Yunnan area of Southwest China. Earthq. Sci., 25(1), 25–34. https://doi.org/10.1007/s11589-012-0828-4

Sun, Y. J., Zhao, X. Y., Huang, Y., Yang, H., and Li, F. (2017). Characteristics of focal mechanisms and stress field of Yunnan area. Seismol. Geol. (in Chinese) , 39(2), 390–407. https://doi.org/10.3969/j.issn.0253-4967.2017.02.009

Wang, L. L., Wang, Q. H., Zhang, Y., and Wang, Y. (2016). Analysis of current activity of main faults in Yunnan region based on GPS. J. Inst. Dis. Prev. (in Chinese) , 18(1), 1–8. https://doi.org/10.3969/j.issn.1673-8047.2016.01.001

Wang, Y. Z., Wang, E. N., Shen, Z. K., Wang, M., Gai, W. J., Qiao, X. J., Meng, G. J., Li, T. M., Tao, W., … Li, P. (2008). GPS-constrained inversion of present-day slip rates along major faults of the Sichuan-Yunnan region, China. Sci. China Ser. D Earth Sci., 51(9), 1267–1283. https://doi.org/10.1007/s11430-008-0106-4

Wessel, P., and Smith, W. H. F. (1998). New, improved version of the Generic Mapping Tools released, EOS Trans. AGU, 79, 579.

Wu, J. P., Ming, Y. H., and Wang, C. Y. (2004). Source mechanism of small-to-moderate earthquakes and tectonic stress field in Yunnan province. Acta Seismol. Sin. (in Chinese) , 26(5), 457–465. https://doi.org/10.3321/j.issn:0253-3782.2004.05.001

Xie, F. R., Zhu, J. Z., Liang, H. Q., and Liu, G. X. (1993). Basic features of modern tectonic stress field in Southwest China. Acta Seismol. Sin. (in Chinese) , 15(4), 407–417.

Xu, Z. G., Huang, Z. C., Wang, L. S., Xu, M. J., Ding, Z. F., Wang, P., Mi, N., Yu, D. Y., and Li, H. (2016). Crustal stress field in Yunnan: Implications for crust-mantle coupling. Earthq. Sci., 29(2), 105–115. https://doi.org/10.1007/s11589-016-0146-3

Xu, Z. H., Wang, S. Y., Huang, Y. R., Gao, A. J., Jin, X. F., and Chang, X. D. (1987). Directions of mean stress axes in southwestern China deduced from microearthquake data. Acta Geophys. Sin. (in Chinese) , 30(5), 476–486.

Zhao, B., Huang, Y., Zhang, C. H., Wang, W., Tan, K., and Du, R. L. (2015). Crustal deformation on the Chinese mainland during 1998-2014 based on GPS data. Geodesy Geodyn., 6(1), 7–15. https://doi.org/10.1016/j.geog.2014.12.006

Zhao, L., Luo, Y., Liu, T., and Luo, Y. (2013). Earthquake focal mechanisms in Yunnan and their inference on the regional stress field. Bull. Seismol. Soc. Am., 103(4), 2498–2507. https://doi.org/10.1785/0120120309

Zhao, L. S., and Helmberger, D. V. (1994). Source estimation from broadband regional seismograms. Bull. Seismol. Soc. Am., 84(1), 91–104.

Zheng, Y., Ma, H. S., Lü, J., Ni, S. D., Li, Y. C., and Wei, S. J. (2009). Source mechanism of strong aftershocks (MS≥5.6) of the 2008/05/12 Wenchuan earthquake and the implication for seismotectonics. Sci. China Ser. D: Earth Sci., 52(6), 739–753. https://doi.org/10.1007/s11430-009-0074-3

Zhong, J. M., and Cheng, W. Z. (2006). Determination of directions of the mean stress field in Sichuan-Yunnan region from a number of focal mechanism solutions. Acta Seismol. Sin. (in Chinese) , 28(4), 337–346. https://doi.org/10.3321/j.issn:0253-3782.2006.04.001

Zhu, L. P., and Helmberger, D. V. (1996). Advancement in source estimation techniques using broadband regional seismograms. Bull. Seismol. Soc. Am., 86(5), 1634–1641.

Zhu, L. P., and Ben-Zion, Y. (2013). Parametrization of general seismic potency and moment tensors for source inversion of seismic waveform data. Geophys. J. Int., 194(2), 839–843. https://doi.org/10.1093/gji/ggt137

[1]

Zhi Wei, Li Zhao, 2019: Lg-Q model and its implication on high-frequency ground motion for earthquakes in the Sichuan and Yunnan region, Earth and Planetary Physics, 3, 526-536. doi: 10.26464/epp2019054

[2]

ZhiGao Yang, Jie Liu, Xue-Mei Zhang, WenZe Deng, GuangBao Du, XiYan Wu, 2021: A preliminary report of the Yangbi, Yunnan, MS6.4 earthquake of May 21, 2021, Earth and Planetary Physics, 5, 362-364. doi: 10.26464/epp2021036

[3]

ChengWei Yang, ChengHu Wang, GuiYun Gao, Pu Wang, 2022: Cretaceous–Cenozoic regional stress field evolution from borehole imaging in the southern Jinzhou area, western Liaoning, North China Craton, Earth and Planetary Physics, 6, 123-134. doi: 10.26464/epp2022001

[4]

DaHu Li, ZhiFeng Ding, Yan Zhan, PingPing Wu, LiJun Chang, XiangYu Sun, 2021: Upper crustal velocity and seismogenic environment of the M7.0 Jiuzhaigou earthquake region in Sichuan, China, Earth and Planetary Physics, 5, 348-361. doi: 10.26464/epp2021038

[5]

Qi Zhang, YongHong Zhao, Hang Wang, Muhammad Irfan Ehsan, JiaYing Yang, Gang Tian, AnDong Xu, Ru Liu, YanJun Xiao, 2020: Evolution of the deformation field and earthquake fracture precursors of strike-slip faults, Earth and Planetary Physics, 4, 151-162. doi: 10.26464/epp2020021

[6]

Xu Zhang, Zhen Fu, LiSheng Xu, ChunLai Li, Hong Fu, 2019: The 2018 MS 5.9 Mojiang Earthquake: Source model and intensity based on near-field seismic recordings, Earth and Planetary Physics, 3, 268-281. doi: 10.26464/epp2019028

[7]

Ru Liu, YongHong Zhao, JiaYing Yang, Qi Zhang, AnDong Xu, 2019: Deformation field around a thrust fault: A comparison between laboratory results and GPS observations of the 2008 Wenchuan earthquake, Earth and Planetary Physics, 3, 501-509. doi: 10.26464/epp2019047

[8]

LeLin Xing, ZiWei Liu, JianGang Jia, ShuQing Wu, ZhengSong Chen, XiaoWei Niu, 2021: Far-field coseismic gravity changes related to the 2015 MW7.8 Nepal (Gorkha) earthquake observed by superconducting gravimeters in China continent, Earth and Planetary Physics, 5, 141-148. doi: 10.26464/epp2021018

[9]

Pan Yan, ZhiYong Xiao, YiZhen Ma, YiChen Wang, Jiang Pu, 2019: Formation mechanism of the Lidang circular structure in the Guangxi Province, Earth and Planetary Physics, 3, 298-304. doi: 10.26464/epp2019031

[10]

HongLin Jin, Yuan Gao, XiaoNing Su, GuangYu Fu, 2019: Contemporary crustal tectonic movement in the southern Sichuan-Yunnan block based on dense GPS observation data, Earth and Planetary Physics, 3, 53-61. doi: 10.26464/epp2019006

[11]

SuPing Duan, Chi Wang, Weining William Liu, ZhaoHai He, 2021: Characteristics of magnetic dipolarizations in the vicinity of the substorm onset region observed by THEMIS, Earth and Planetary Physics, 5, 239-250. doi: 10.26464/epp2021031

[12]

Yi Liu, Chen Zhou, Tong Xu, Qiong Tang, ZhongXin Deng, GuanYi Chen, ZhuangKai Wang, 2021: Review of ionospheric irregularities and ionospheric electrodynamic coupling in the middle latitude region, Earth and Planetary Physics, 5, 462-482. doi: 10.26464/epp2021025

[13]

Safi Ullah, HaiLong Li, Abdur Rauf, Lin Meng, Bin Wang, ShuCan Ge, MaoYan Wang, 2021: Effect of ions on conductivity and permittivity in the Polar Mesosphere Summer Echoes region, Earth and Planetary Physics, 5, 196-204. doi: 10.26464/epp2021016

[14]

YuLan Li, BaoShan Wang, RiZheng He, HongWei Zheng, JiangYong Yan, Yao Li, 2018: Fine relocation, mechanism, and tectonic indications of middle-small earthquakes in the Central Tibetan Plateau, Earth and Planetary Physics, 2, 406-419. doi: 10.26464/epp2018038

[15]

Yue Shen, QiuYu Wang, WeiLong Rao, WenKe Sun, 2022: Spatial distribution characteristics and mechanism of nonhydrological time-variable gravity in China continent, Earth and Planetary Physics, 6, 96-107. doi: 10.26464/epp2022009

[16]

Qiu-Gang Zong, Hui Zhang, 2018: In situ detection of the electron diffusion region of collisionless magnetic reconnection at the high-latitude magnetopause, Earth and Planetary Physics, 2, 231-237. doi: 10.26464/epp2018022

[17]

Wen Yi, XiangHui Xue, JinSong Chen, TingDi Chen, Na Li, 2019: Quasi-90-day oscillation observed in the MLT region at low latitudes from the Kunming meteor radar and SABER, Earth and Planetary Physics, 3, 136-146. doi: 10.26464/epp2019013

[18]

Chao Xiao, WenLong Liu, DianJun Zhang, Zhao Zhang, 2020: A normalized statistical study of Earth’s cusp region based on nine-years of Cluster measurements, Earth and Planetary Physics, 4, 266-273. doi: 10.26464/epp2020031

[19]

Rui Yan, YiBing Guan, XuHui Shen, JianPing Huang, XueMin Zhang, Chao Liu, DaPeng Liu, 2018: The Langmuir Probe onboard CSES: data inversion analysis method and first results, Earth and Planetary Physics, 2, 479-488. doi: 10.26464/epp2018046

[20]

Chun-Feng Li, Jian Wang, 2018: Thermal structures of the Pacific lithosphere from magnetic anomaly inversion, Earth and Planetary Physics, 2, 52-66. doi: 10.26464/epp2018005

Article Metrics
  • PDF Downloads()
  • Abstract views()
  • HTML views()
  • Cited by(0)
Catalog

Figures And Tables

Regional stress field in Yunnan revealed by the focal mechanisms of moderate and small earthquakes

JianHui Tian, Yan Luo, Li Zhao