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The focal depths of the 2008 Panzhihua earthquake sequence and the stress field in the source region

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Abstract

Focal depths of the 2008 MS6.1 Panzhihua earthquake sequence and tectonic stress field in the source area are investigated. Source depths of 24 earthquakes in Panzhihua earthquake sequence with a magnitude M≥3.0 were determined using the seismic depth phase sPL; additionally, the focal depths of 232 earthquakes were measured by fitting the three-component waveforms of the P and S waves. The source depth of the main shock is ~12 km. The majority of the aftershocks with magnitude M≥3.0 occurred in the brittle upper crust at the depths range of 12–18 km. Further, the Source mechanisms of the 232 events around the Panzhihua earthquake source area were determined, and the results show that the earthquakes have predominantly strike-slip mechanisms in the Dianzhong Block, but display complexity of the focal mechanisms outside and near the boundary of the Dianzhong block. The 232 earthquake mechanisms from this study are combined with the solutions from the Global Centroid Moment Tensor (GCMT) catalog to derive 2D stress field. The inversion results show that the Dianzhong block is predominantly under a strike slip faulting regime and the direction of the maximum principal compression σ1 is northwest-southeast (NW-SE)-trending. The distribution is coincide with GPS velocity field. However, orientations of principal stress axes as well as the faulting types change outside and near the Dianzhong block. The results show that the tectonic stress field in the study area is predominantly controlled by the southeast (SE)-trending horizontal movement and clockwise rotation of the Dianzhong block as a result of the eastward movement of eastern Tibetan meeting the old and rigid South China block (SCB). The Panzhihua earthquake ruptured at ~12 km depth where the tectonic stress regime is under the SE-direction horizontal compression and the NE-direction horizontal extension.

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References

  • Audet P. 2015. Layered crustal anisotropy around the San Andreas fault near Parkfield, California. J Geophys Res-Solid Earth, 120: 3527–3543

    Google Scholar 

  • Beroza G C, Zoback M D. 1993. Mechanism diversity of the Loma Prieta Aftershocks and the mechanics of mainshock-aftershock interaction. Science, 259: 210–213

    Google Scholar 

  • Boness N L, Zoback M D. 2006. Mapping stress and structurally controlled crustal shear velocity anisotropy in California. Geology, 34: 825–828

    Google Scholar 

  • Chen W W, Wang D C, Wei S J. 2013. A study on the uncertainties of the centroid depth of the 2013 Lushan earthquake from teleseimic body wave data. Earthq Sci, 26: 161–168

    Google Scholar 

  • Crampin S, McGonigle R, Bamford D. 1980. Estimating crack parameters from observations of P-wave velocity anisotropy. Geophysics, 45: 345–360

    Google Scholar 

  • Cheng J, Xu X W, Gan W J, Ma W T, Chen W T, Zhang Y. 2012. Block model and dynamic impliation from the earthquake activities and crusttal motion in the southeastren margin of Tibetan Plateau (in Chinese). Chin J Georhys, 55: 1198–1212

    Google Scholar 

  • Chong J J, Ni S D, Zeng X F. 2010. sPL, an effective seismic phase for determining focal depth at near distance (in Chinese). Chin J Georhys, 53: 2620–2630

    Google Scholar 

  • Cui X F, Xie F R, Zhang H Y. 2006. Recent tectonic stress field zoning in Sichuan Yunnan region and its dynamic interest (in Chinese). Acta Seismol Sin, 28: 451–461

    Google Scholar 

  • Hardebeck J L, Michael A J. 2006. Damped regional-scale stress inversions: Methodology and examples for southern California and the Coalinga aftershock sequence. J Geophys Res, 111: B11310

    Google Scholar 

  • Jia K, Zhou S Y. 2012. Inference of source paramaters of historical major earthquakes from 1900 to 1970 in southwestern China and analusis of their uncertainties (in Chinese). Chin J Geophys, 55: 2948–2962

    Google Scholar 

  • Li Z W, Huang Z B, Wang X X, Han L B, Chen W W, Bao F. 2015. A study on the reliability of M4–5 earthquakes with anomalous focal depth in the USGS earthquake catalog: Several earthquakes in the Nouth-South Seismic Belt (in Chinese). Chin J Geophys, 58: 1236–1250

    Google Scholar 

  • Liang S H, Shu P Y, Li Y M, Zhu P D, Zhang L M. 1986. Earthquake distributions and the characteristics of tectonic stress field in Panxi region, southwest China (in Chinese). Chin J Geophys, 29: 557–566

    Google Scholar 

  • Liu M F. 2008. A study on genesis of Hongge hot spring in Yanbian, Sichuan Province (in Chinese). Coal Geol China, 20: 45–48

    Google Scholar 

  • Long F, Zhang Y J, Wen X Z, Ni S D, Zhang Z W. 2010. Focal mechanism solutions of ML≥4.0 events in the MS6.1 Panzhihua-Huili earthquake sequence of Aug 30, 2008 (in Chinese). Chin J Geophys, 53: 2852–2860

    Google Scholar 

  • Luo Y, Ni S D, Zeng X F, Xie J, Chen Y, Long F. 2011. The M5.0 Suining-Tongnan (China) earthquake of 31 January 2010: A destructive earthquake occurring in sedimentary cover (in Chinese). Chin Sci Bull, 56: 147–152

    Google Scholar 

  • Luo Y, Ni S D, Zeng X F, Zheng Y, Chen Q F, Chen Y. 2010. A shallow aftershock sequence in the north-eastern end of the Wenchuan earthquake aftershock zone. Sci China Earth Sci, 53: 1655–1664

    Google Scholar 

  • Lay T, Wallace T C. 1995. Modern Global Seismology. San Diego: Academic Press. 1–521

    Google Scholar 

  • Michael A J. 1984. Determination of stress from slip data: Faults and folds. J Geophys Res, 89: 11517–11526

    Google Scholar 

  • Michael A J. 1987. Use of focal mechanisms to determine stress: A control study. J Geophys Res, 92: 357–368

    Google Scholar 

  • Michael A J. 1991. Spatial variations in stress within the 1987 Whittier Narrows, California, aftershock sequence: New techniques and results. J Geophys Res, 96: 6303–6319

    Google Scholar 

  • Rasendra N, Bonnin M, Mazzotti S, Tiberi C. 2014. Crustal and upper-mantle anisotropy related to fossilized transpression fabric along the Denali Fault, northern Canadian Cordillera. Bull Seismol Soc Am, 104: 1964–1975

    Google Scholar 

  • Saikia C K, Woods B B, Thio H K. 2001. Calibration of the regional crustal waveguide and the retrieval of source parameters using waveform modeling. Pure Appl Geophys, 158: 1301–1338

    Google Scholar 

  • Shi Y T, Gao Y, Su Y J, Wang Q. 2012. Shear-wave splitting beneath Yunnan area of Southwest China. Earthq Sci, 25: 25–34

    Google Scholar 

  • Stein S, Wiens D A. 1986. Depth determination for shallow teleseismic earthquakes: Methods and results. Rev Geophys, 24: 806–832

    Google Scholar 

  • Wang Z J, Chong J J, Ni S D, Romanowicz B. 2011. Determination of focal depth by two waveformbased methods: A case study for the 2008 Panzhihua earthquake. Earthq Sci, 24: 321–328

    Google Scholar 

  • Wang C Y, Wu J P, Lou H, Zhou M D, Bai Z M. 2003. Crustal P wave velocity structure in western Sichuan and eastern Tibet (in Chinese). Sci China Ser D-Earth Sci, 33: 181–189

    Google Scholar 

  • Wu J P, Ming Y H, Wang C Y. 2004. Source mechanism of small-to-moderate earthquakes and tectonic stress field in Yunnan Province (in Chinese). Acta Seismol Sin, 26: 457–465

    Google Scholar 

  • Xie F R, Chen Q C, Cui X F, Li H, Yang S X, Guo Q L, Chen L W, Xu Z H, Zhang Y S, Dou S Q, Zhao J T, Zhang Z S, Liu C Y, Wang G J. 2007. Basic database of curstal stress environment in mainlan China (in Chinese). Prog Geophys, 22: 131–136

    Google Scholar 

  • Xiong S B, Zhen Y, Yin Z X, Zeng X X, Quan Y L, Sun K Z. 1993. The 2-D structure and its tectonic implications of the crust in the Lijiang-Panzhihua-Zhehai region (in Chinese. Chin J Geophys, 36: 434–444

    Google Scholar 

  • Xu X W, Wen X Z, Zhen R Z, Ma W T, Song F M. 2003. The latest tectonic variation patterns of active blocks in Sichuan-Yunnan area and their dynamic sources (in Chinese). Sci China Ser D-Earth Sci, 33: 151–162

    Google Scholar 

  • Xu Y, Herrmann R B, Koper K D. 2010. Source parameters of regional small-to-moderate earthquakes in the Yunnan-Sichuan region of China. Bull Seismol Soc Am, 100: 2518–2531

    Google Scholar 

  • Xu Z H. 2001. A present day tectonic stress map for eastern Asia region (in Chinese). Acta Seismol Sin, 23: 492–501

    Google Scholar 

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

    Google Scholar 

  • Xu Z H, Wang S Y, Huang Y R, Gao A J. 1989. The tectonic stress field of Chinese continent deduced from a great number of earthquakes (in Chinese). Chin J Geophys, 32: 636–647

    Google Scholar 

  • Yang W Z, Hauksson E. 2013. The tectonic crustal stress field and style of faulting along the Pacific North America Plate boundary in Southern California. Geophys J Int, 194: 100–117

    Google Scholar 

  • Yao H J, van der Hilst R D, Montagner J P. 2010. Heterogeneity and anisotropy of the lithosphere of SE Tibet from surface wave array tomography. J Geophys Res, 115: B12307

    Google Scholar 

  • Zhao B, Huang Y, Zhang C H, Wang W, Tan K, Du R L. 2015. Crustal deformation on the Chinese mainland during 1998–2014 based on GPS data. Geodesy Geodyn, 6: 7–15

    Google Scholar 

  • Zhao L S, Helmberger D V. 1994. Source estimation from broadband regional seismograms. Bull Seismol Soc Am, 84: 91–104

    Google Scholar 

  • Zhao L, Luo Y, Liu T Y, Luo Y J. 2013. Earthquake focal mechanisms in Yunnan and their inference on the regional stress field. Bull Seismol Soc Am, 103: 2498–2507

    Google Scholar 

  • Zhu L P, Helmberger D V. 1996. Advancement in source estimation techniques using broadband regional seismograms. Bull Seismol Soc Am, 86: 1631–1641

    Google Scholar 

  • Zhu L P, Rivera L A. 2002. A note on the dynamic and static displacements from a point source in multilayered media. Geophys J Int, 148: 619–627

    Google Scholar 

  • Zhang P Z, Wen X Z, Xu X W, Gan W J, Wang M, Shen Z K, Wang Q L, Huang Y, Zhen Y, Li X J, Zhang Z Q, Ma S L, Ran Y K, Liu Q Y, Ding Z F, Wu J P. 2009. Tectonic model of the great Wenchuan earthquake of May 12, 2008, Sichuan, China (in Chinese). Chin Sci Bull, 54: 944–953

    Google Scholar 

  • Zhang R Q, Wu Q J. 2008. Focal depth for an earthquake (MS5.6) on August 31, 2008 in Panzhihua of Sichuan province (in Chinese). Recent Develop World Seismol, 12: 1–5

    Google Scholar 

  • Zhu A L, Xu X W, Zhou Y S, Yin J Y, Gan W J, Chen G H. 2005. Relocation of small earthquakes in western Sichuan, China and its implications for active tectonics (in Chinese). Chin J Geophys, 48: 629–636

    Google Scholar 

  • Zhu J S, Cao J M, Liu S H, Jiang G F, Yu M, Jiang H L. 1984. A preliminary investigation on crustal structure of western Sichuan by explosion seismology (in Chinese). Chendu Col Geol, 3: 111–122

    Google Scholar 

Download references

Acknowledgements

We thank the chief editor, the associated editor, and the anonymous reviewers whose numerous constructive suggestions and comments helped us to improve our manuscript. This work was supported by the National Natural Science Foundation of China (Grant No. 41974063), the Basic Research Fund of the Institute of Earthquake Forecasting, China Earthquake Administration (Grant No. 2015IES010302), and the State Key Laboratory of Geodesy and Earth’s Dynamics, Institute of Geodesy and Geophysics, Chinese Academy of Sciences (Grant No. SKLGED2018-4-3-E).

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  1. Key Laboratory of Earthquake Prediction, Institute of Earthquake Forecasting, CEA, Beijing, 100036, China

    Yan Luo & Jianhui Tian

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

    Li Zhao

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  1. Yan Luo
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  2. Li Zhao
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Correspondence to Yan Luo.

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Luo, Y., Zhao, L. & Tian, J. The focal depths of the 2008 Panzhihua earthquake sequence and the stress field in the source region. Sci. China Earth Sci. 63, 439–451 (2020). https://doi.org/10.1007/s11430-018-9441-6

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