Abstract
The ENE striking Longmu Co fault and the North Altyn Tagh left-lateral slip fault have led to the complex regional structure in the northwestern Tibetan Plateau, resulting in a series of normal faulting and strike slip faulting earthquakes. Using both the ascending and descending Sentinel-1A/B radar images, we depict the coseismic deformation caused by the 2020 Yutian Mw 6.4 earthquake with a peak subsidence of ~ 20 cm. We determine the seismogenic fault geometry by applying the Bayesian approach with a Markov Chain Monte Carlo sampling method, which can better characterize the posterior probability density functions of the source model parameters. The estimation results reveal that the earthquake is a normal faulting event with a moderate strike slip component. Based on the optimal fault geometry model, we extend the fault plane and invert for the distributed coseismic slip model. The optimal slip model shows that the coseismic slip is mainly concentrated at shallow depths of 3–10 km with a maximum slip of ~ 1.0 m. Our preferred geodetic coseismic model exhibits no surface rupture, which may likely be due to the shallow slip deficit in the uppermost crust. We calculate the combined loading effect of the Coulomb failure stress changes induced by the coseismic dislocations and postseismic viscoelastic relaxation of the 2008 Mw 7.1, 2012 Mw 6.4 and 2014 Mw 6.9 Yutian events. Our study demonstrates that the three preceding major Yutian shocks were insufficient to trigger the 2020 Yutian earthquake, which we consider perhaps reflects the natural release of elastic strain accumulated mainly through localized tectonic movement. We attribute the 2020 Yutian event to the release of extensional stress in a stepover zone controlled by the Longmu Co and the North Altyn Tagh sinistral strike slip fault systems. The seismic risk in the southwest end of the North Altyn Tagh fault has been elevated by the Yutian earthquake sequences, which require future attention.
This is a preview of subscription content, log in via an institution to check access.
source parameters for the 2020 Mw 6.4 Yutian earthquake in the northwest Tibet. The scatter dots indicates occurrence frequency, with warm colors denoting high frequency and clod colors denoting low frequency. Bottom row: Histograms of model parameters; the best models are shown in thick red line with 95% confidence interval bounds in red dashed lines
Similar content being viewed by others
Availability of data and materials
The data sets used during the current study are available from the corresponding author on a reasonable request.
References
Amey, R., Hooper, A., & Walters, R. (2018). A Bayesian method for incorporating self-similarity into earthquake slip inversions. Journal of Geophysical Research: Solid Earth, 123, 6052–6071. https://doi.org/10.1029/2017JB015316
Armijo, R., Tapponnier, P., Mercier, J., & Han, T. (1986). Quaternary extension in southern Tibet: field observations and tectonic implications. Journal of Geophysical Research: Solid Earth, 91, 13803–13872. https://doi.org/10.1029/JB091iB14p13803
Bagnardi, M., & Hooper, A. (2018). Inversion of surface deformation data for rapid estimates of source parameters and uncertainties: a Bayesian approach. Geochemistry, Geophysics, Geosystems, 19, 2194–2211. https://doi.org/10.1029/2018GC007585
Bassin, C., Laske, G., & Masters, G. (2000). The current limits of resolution for surface wave tomography in North America. Eos, Transactions of the American Geophysical Union, 81, F897
Beaumont, C., Jamieson, R. A., Nguyen, M. H., & Lee, B. (2001). Himalayan tectonics explained by extrusion of a low-viscosity crustal channel coupled to focused surface denudation. Nature, 414(6865), 738–742. https://doi.org/10.1038/414738a
Bie, L., & Ryder, I. (2014). Recent seismic and aseismic activity in the Ashikule stepover zone NW Tibet. Geophysical Journal International, 198(3), 1632–1643. https://doi.org/10.1093/gji/ggu230
Bie, L., Ryder, I., Nippress, S., & Bürgmann, R. (2014). Coseismic and post-seismic activity associated with the 2008 Mw 6.3 Damxung earthquake, Tibet, constrained by InSAR. Geophysical Journal International, 196(2), 788–803. https://doi.org/10.1093/gji/ggt444
Chen, C., & Zebker, H. (2000). Network approaches to two-dimensional phase unwrapping: intractability and two new algorithms. Journal of the Optical Society of America A. Optics and Image Science, 17, 401–414. https://doi.org/10.1364/JOSAA.17.000401
Chen, H., Pan, Y., Dong, P., Zhang, H., & Shi, Y. (2014). Analysis of the stress environment of the 2008 and 2014 Yutian MS 7.3 earthquakes. China Journal Geophysics, 57(10), 3238–3246. https://doi.org/10.6038/cjg20141012
Chen, W., Qiao, X., Xiong, W., Yu, P., & Nie, Z. (2019). The 2007 Ning’er Mw 7.3 earthquake: A shallow rupture in Southwest China revealed by InSAR measurements. Earth Space Science. https://doi.org/10.1029/2019EA000555
Copley, A., Avouac, J. P., & Wernicke, B. P. (2011). Evidence for mechanical coupling and strong Indian lower crust beneath southern Tibet. Nature, 472(7341), 79–81. https://doi.org/10.1038/nature09926
Elliott, J., Walters, R. J., England, P. C., Jackson, J. A., Li, Z., & Parsons, B. (2010). Extension on the Tibetan plateau: recent normal faulting measured by InSAR and body wave seismology. Geophysical Journal International, 183(2), 503–535
Farr, T., Rosen, P., Caro, E., Crippen, R., Duren, R., Hensley, S., Kobrick, M., Paller, M., Rodriguez, E., & Roth, L. (2007). The shuttle radartopography mission. Review of Geophysics. https://doi.org/10.1029/2005RG000183
Fialko, Y., Sandwell, D., Simons, M., et al. (2005). Three-dimensional deformation caused by the Bam, Iran, earthquake and the origin of shallow slip deficit. Nature, 435(7040), 295–299. https://doi.org/10.1038/nature03425
Fukuda, J., & Johnson, K. (2010). Mixed linear-non-linear inversion of crustal deformation data: Bayesian inference of model, weighting and regularization parameters. Geophysical Journal International. https://doi.org/10.1111/j.1365-246X.2010.04564.x
Gunawan, E., Widiyantoro, S., Supendi, P., & Nishimura, T. (2020). Identifying the most explainable fault ruptured of the 2018 Palu-Donggala earthquake in Indonesia using coulomb failure stress and geological field report. Geodesy and Geodynamics, 11(4), 252–257. https://doi.org/10.1016/j.geog.2020.04.004
Guo, S., Zhang, G., & Zhu, Y. (2019). Gravity changes and crustaldeformations before the Menyuan, Qinghai Ms 6.4 earthquake of 2016. Geodesy and Geodynamics, 10(4), 315–320. https://doi.org/10.1016/j.geog.2019.03.007
He, P., Wen, Y., Ding, K., & Xu, C. (2020). Normal faulting in the 2020 Mw 6.4 Yutian event: Implications for ongoing E-W thinning in northern Tibet. Remote Sensing. https://doi.org/10.3390/RS12183012
Jia, K., Zhou, S., & Wang, R. (2012). Stress interactions within the strong earthquake sequence from 2001 to 2010 in the Bayankala block of eastern Tibet. Bulletin of the Seismological Society of America, 102(5), 2157–2164. https://doi.org/10.1785/0120110333
Jónsson, S., Zebker, H., Segall, P., & Amelung, F. (2002). Fault slip distribution of the 1999 Mw 7.1 Hector mine, California, earthquake, estimated from satellite radar and GPS measurements. Bulletin of the Seismological Society of America, 92(4), 1377–1389. https://doi.org/10.1785/0120000922
Kaneko, Y., & Fialko, Y. (2011). Shallow slip deficit due to large strike-slip earthquakes in dynamic rupture simulations with elasto-plastic off-fault response. Geophysical Journal International, 186(3), 1389–1403. https://doi.org/10.1111/j.1365-246X.2011.05117.x
Kapp, P., Taylor, M., Stockli, D., et al. (2008). Development of active low-angle normal fault systems during orogenic collapse: Insight from Tibet. Geology, 36(1), 7–10. https://doi.org/10.1029/2001TC001332
Kostrov, B. V. (1974). Seismic moment and energy of earthquakes, and seismic flow of rock . Izv. Acad. Sci USSR Phys Solid Earth Eng. Transl, 1, 23–44
Lewis, T., Hyndman, R., & Flück, P. (2003). Heat flow, heat generation, and crustal temperatures in the northern Canadian Cordillera: thermal control of tectonics. Journal of Geophysical Research: Solid Earth. https://doi.org/10.1029/2002JB002090
Li, Y., Chen, L., Liu, S., et al. (2015). Coseismic Coulomb stress changes caused by the Mw6.9 Yutian earthquake in 2014 and its correlation to the 2008 Mw 7.2 Yutian earthquake. Journal of Asian Earth Sciences, 105, 468–475. https://doi.org/10.1016/j.jseaes.2015.02.025
Li, X., Xu, W., Jónsson, S., Klinger, Y., & Zhang, G. (2020). Source Model of the 2014 Mw 6.9 Yutian Earthquake at the Southwestern End of the Altyn Tagh Fault in Tibet Estimated from Satellite Images. Seismological Research Letters. https://doi.org/10.1785/0220190361
Lin, A., Jia, D., Rao, G., Yan, B., Wu, X., & Ren, Z. (2011). Recurrent morphogenic earthquakes in the past millennium along the strike-slip Yushu fault, central Tibetan Plateau. Bulletin of the Seismological Society of America, 101(6), 2755–2764. https://doi.org/10.1785/0120100274
Liu, B., Shi, B., & Lei, J. (2015). Effects of the 2008 and 2014 Yutian earthquake on seismic probabilities of adjacent faults. Chinese Journal of Geophysics-Chinese Edition, 58(2), 463–473. https://doi.org/10.6038/cjg20150210
Oglesby, D. D. (2005). The dynamics of strike-slip step-overs with linking dip-slip faults. Bulletin of the Seismological Society of America, 95(5), 1604–1622. https://doi.org/10.1785/0120050058
Okada, Y. (1985). Surface deformation due to shear and tensile faults in a half-space. Bulletin of the Seismological Society of America, 75(4), 1135–1154
Qiu, J., Liu, L., Wang, C., & Wang, Y. (2019). Present-day tectonic activity along the central section of the Altyn Tagh fault derived from time series InSAR. Geodesy and Geodynamics, 10(4), 307–314. https://doi.org/10.1016/j.geog.2019.03.008
Ren, J., Xu, X., Yeats, R., & Zhang, S. (2013). Millennial slip rates of the Tazang fault, the eastern termination of Kunlun fault: implications for strain partitioning in eastern Tibet. Tectonophysics, 608, 1180–1200. https://doi.org/10.1016/j.tecto.2013.06.026
Ryder, I., Bürgmann, R., & Sun, J. (2010). Tandem afterslip on connected fault planes following the 2008 Nima-Gaize (Tibet) earthquake. Journal of Geophysical Research: Solid Earth, 115(B3), B03404. https://doi.org/10.1029/2009JB006423
Ryder, I., Bürgmann, R., & Pollitz, F. (2011). Lower crustal relaxation beneath the Tibetan Plateau and Qaidam Basin following the 2001 Kokoxili earthquake. Geophysical Journal International, 187(2), 613–630. https://doi.org/10.1111/j.1365-246X.2011.05179.x
Ryder I, Bürgmann R, Fielding E (2012) Static stress interactions in extensional earthquake sequences: An example from the South Lunggar Rift Tibet. Journal of Geophysical Research: Solid Earth https://doi.org/10.1029/2012jb009365
Sandwell, D., Mellors, R., Tong, X. P., Wei, M., & Wessel, P. (2011). Open radar interferometry software for mapping surface deformation. Eos, Transactions of the American Geophysical Union. https://doi.org/10.1029/2011EO280002
Shan, X., Zhang, G., Wang, C., et al. (2011). Source characteristics of the Yutian earthquake in 2008 from inversion of the co-seismic deformation field mapped by InSAR. Journal of Asian Earth Sciences, 40(4), 935–942. https://doi.org/10.1016/j.jseaes.2010.05.011
Shen, Z., Jackson, D., & Kagan, Y. (2007). Implications of geodetic strain rate for future earthquakes, with a five-year forecast of M5 earthquakes in southern California. Seismological Research Letters, 78(1), 116–120. https://doi.org/10.1785/gssrl.78.1.116
Tapponnier, P., Xu, Z., Roger, F., Meyer, B., Arnaud, N., Wittlinger, G., & Yang, J. (2001). Oblique stepwise rise and growth of the Tibet Plateau. Science, 294(5547), 1671–1677. https://doi.org/10.1126/science.105978
Taylor, M., & Yin, A. (2009). Active structures of the Himalayan-Tibetan orogen and their relationships to earthquake distribution, contemporary strain field, and Cenozoic volcanism. Geosphere, 5(3), 199–214. https://doi.org/10.1130/GES00217.1
Walcott, R. (1984). The kinematics of the plate boundary zone through New Zealand: a comparison of short- and long-term deformations. Geophysical Journal International, 79(2), 613–633
Wang, Q., Yang, W. B., Zhang, Z. F., Yang, Y. S., Wu, J. G., & Dong, A. G. (2005). Geological characteristics of Neogene volcanic rocks in the Heishi North Lake area, Northwest Tibet, and their implications for the Neogene tectonic evolution. Geological Bulletin of China, 24(1), 80–86 (in Chinese).
Wang, R., Lorenzo-Martín, F., & Roth, F. (2006). PSGRN/PSCMP—A new code for calculating co-and post-seismic deformation, geoid and gravity changes based on the viscoelastic-gravitational dislocation theory. Computers & Geosciences, 32(4), 527–541. https://doi.org/10.1016/j.cageo.2005.08.006
Wang, H., Elliott, J. R., Craig, T. J., Wright, T. J., Zeng, J. L., & Hooper, A. (2014). Normal faulting sequence in the Pumqu-Xainza Rift constrained by InSAR and teleseismic body-wave seismology. Geochemistry, Geophysics, Geosystems, 15, 2947–2952. https://doi.org/10.1002/2014GC005369
Wang, H., Cao, J., Hong, S., Xu, Y., & Jing, F. (2016). Viscoelastic stress transfer between 2008 and 2014 Yutian M7 earthquakes, Xinjiang. Seismology and Geology, 38(3), 646–655. https://doi.org/10.3969/j.issn.0253-4967.2016.03.011
Wessel, P., Smith, W. H. F., Scharroo, R., Luis, J., & Wobbe, F. (2013). Generic Mapping Tools: Improved Version Released. Eos, Transactions of the American Geophysical Union, 94(45), 409–410. https://doi.org/10.1002/2013eo450001
Wu, C., Zhang, Z., Zhao, C., et al. (2014). Yutian MS 7.3 earthquake: Structural response of the Bayankala tectonic-block to eastward extrusion. Chinese Journal of Geophysics-Chinese Edition, 57(10), 3226–3237. https://doi.org/10.6038/cjg20141011
Xiong, W., Qiao, X., Liu, G., Chen, W., & Nie, Z. (2019). Coulomb stress evolution along the Kongur Extensional System since 1895 and present seismic hazard. Geodesy and Geodynamics, 10(1), 1–9. https://doi.org/10.1016/j.geog.2018.11.007
Xu, X., Tan, X., Yu, G., et al. (2013). Normal- and oblique-slip of the 2008 Yutian earthquake: Evidence for eastward block motion, northern Tibetan Plateau. Tectonophysics, 584, 152–165. https://doi.org/10.1016/j.tecto.2012.08.007
Xu, C., Xu, B., Wen, Y., & Liu, Y. (2016). Heterogeneous fault mechanisms of the 6 October 2008 MW 6.3 Dangxiong (Tibet) earthquake using interferometric synthetic aperture radar observations. Remote Sensing, 8(3), 228. https://doi.org/10.3390/rs8030228
Yu, C., Li, Z., Chen, J., et al. (2018). Small Magnitude Co-Seismic Deformation of the 2017 Mw 6.4 Nyingchi Earthquake Revealed by InSAR Measurements with Atmospheric Correction. Remote Sensing, 10(5), 684. https://doi.org/10.3390/rs10050684
Yu, J., Tan, K., Zhang, C., Zhao, B., Wang, D., & Li, Q. (2019). Present-day crustal movement of the Chinese mainland based on Global Navigation Satellite System data from 1998 to 2018. Advances in Space Research. https://doi.org/10.1016/j.asr.2018.10.001
Yu, J., Zhao, B., Xu, W., Wang, D., & Tan, K. (2020). Oblique fault movement during the 2016 Mw 5.9 Zaduo earthquake: insights into regional tectonics of the Qiangtang block Tibetan Plateau. J Seismol, 24, 693–708. https://doi.org/10.1007/s10950-020-09930-7
Zhang, G., Ma, H., Wang, H., & Wang, X. (2005). Boundaries between active-tectonic blocks and strong earthquakes in the China mainland. Chinese Journal Geophysics, 48(3), 602–610 (in Chinese).
Zhang, G., Qu, C., Shan, X., Song, X., Li, Z., & Hu, J. (2011). The coseismic InSAR measurements of 2008 Yutian earthquake and its inversion for source parameters. Chinese Journal Geophysics, 54(11), 2753–2760. https://doi.org/10.3969/j.issn.0001-5733.2011.11.005
Zhao, B., Qi, Y., Wang, D., Yu, J., Li, Q., & Zhang, C. (2018). Coseismic Slip Model of the 2018 M w 7.9 Gulf of Alaska Earthquake and Its Seismic Hazard Implications. Seismological Research Letters, 90, 642–648. https://doi.org/10.1785/0220180141
Acknowledgements
The Sentinel-1A/B InSAR images used in this study were freely available and provided by Sentinels Scientific data Hub of Copernicus and European Space Agency. GNSS raw data were provided by the CMONOC Project (ftp.cgps.ac.cn), which were processed using the latest Bernese GNSS software. The PSGRN/PSCMP packages were provided by Prof. Wang Rongjiang at GeoForschungsZentrum Potsdam. The figures are partly generated by the Generic Mapping Tools (GMT) software package (Wessel et al. 2013).
Funding
This research was supported by the National Key Research and Development Program of China (No. 2018YFC1503601), the Natural Science Foundation of Hubei Province (No. 2019CFB794), and the National Natural Science Foundation of China (No. 42074116).
Author information
Authors and Affiliations
Contributions
JY and BZ conceived and designed the experiments. JY drafted the original manuscript. BZ led the research work, proposed the crucial suggestions of this manuscript. DW and LQ contributed to some parts of the manuscript. All authors read and approved the final manuscript.
Corresponding author
Ethics declarations
Competing interests
The authors declare that they have no competing interests.
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Supplementary Information
Below is the link to the electronic supplementary material.
Rights and permissions
About this article
Cite this article
Yu, J., Wang, D., Zhao, B. et al. Normal Faulting Movement During the 2020 Mw 6.4 Yutian Earthquake: A Shallow Rupture in NW Tibet Revealed by Geodetic Measurements. Pure Appl. Geophys. 178, 1563–1578 (2021). https://doi.org/10.1007/s00024-021-02735-w
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00024-021-02735-w