2016年新西兰凯库拉MW7.8地震同震破裂及子断层间相互影响

doi:10.12196/j.issn.1000-3274.2022.02.010

摘要/Abstract

摘要： 2016年11月13日新西兰南岛东北部凯库拉M_W7.8地震同震破裂比较复杂, 其发震断层多达12条。通过反演InSAR同震位移, 确定了断层同震位错分布。结果表明: 最大位移量发生在Kekerenbgu断层北部, 约13.5 m, 以右旋走滑运动为主, 而最大逆冲错动发生在Jordan Thrust断层和Papatea断层上, 板块界面上的最大滑移位于Jordan Thrust断层下。为进一步分析各子断层破裂间的相互关系, 基于各发震断层同震位错反演结果, 分别计算了破裂过程中先破裂断层在后续破裂断层上的同震库仑应力变化。结果表明: 相邻断层间引起的最大同震库仑应力变化量级在MPa范围, 除Hundalee断层和Jordan Thrust东北部断层上的同震库仑应力减少外, 其他断层都位于库仑应力增加的区域, 增加的量级可达MPa, 远高于一般认为的触发阈值0.01 MPa。据此认为, 在此次地震复杂的多断层破裂过程中, 静态库仑应力是破裂传播和断层触发的关键因素, 在很大程度上促进了后续断层的破裂。

关键词: 2016年凯库拉M_W7.8地震, 同震位错反演, 同震库仑应力, 触发

Abstract: The 2016 Kaikoura M_W7.8 earthquake, occurred in the northern South Island of New Zealand on November 13, 2016, is complex event, in which as many as 12 seismogenenic faults were ruptured. We determined the coseismic slip distribution by inverting the InSAR deformation data. The results show that the maximum horizontal slip occurs in the north of the Kekerenbgu fault (13.5 m) and is dominated by dextral strike-slip, while the maximum thrust dislocation appears in the Jordan Thrust fault and the Papatea fault with the peak slip on the plate interface under the Jordan Thrust fault. Based on the obtained fault slip distributions, we calculated the coseismic Coulomb stress variation caused by the former ruptured faults on the subsequent ruptured faults. The results indicate that the maximum coseismic Coulomb stress variation between adjacent faults reaches up to several mega of Pascal. Except for the reduction of Coulomb stress on the Hundalee fault and the northeastern Jordan Thrust fault, all other faults are located in the region where Coulomb stress increases, which is significantly higher than the generally considered trigger threshold of 0.01 MPa. Therefore, we conclude that static Coulomb stress is a key factor of fault triggering and propagation in the complex multi-fault rupture process of this earthquake.

Key words: the 2016 Kaikoura M_W7.8 earthquake, Coseismic dislocation inversion, Coseismic Coulomb stress, Triggering

中图分类号:

P315.7

耿亚清, 张勇, 邵志刚, 刘琦. 2016年新西兰凯库拉M_W7.8地震同震破裂及子断层间相互影响[J]. 地震, 2022, 42(2): 123-139.

GENG Ya-qing, ZHANG Yong, SHAO Zhi-gang, LIU Qi. Co-seismic Rupture and the Interaction between Sub-faults of the 2016 Kaikoura M_W7.8 Earthquake in New Zealand[J]. EARTHQUAKE, 2022, 42(2): 123-139.

参考文献

[1] Hamling I J, Hreinsdóttir S, Clark K, et al. Complex multifault rupture during the 2016 M_W7.8 Kaikōura earthquake, New Zealand[J]. Science, 2017, 356: 7194.
[2] Kaiser A, Balfour N, Fry B, et al. The 2016 Kaikōura, New Zealand, earthquake: Preliminary seismlogical report[J]. Seismlogical Research Letters, 2017, 88(3): 727-739.
[3] 贺礼家, 冯光财, 冯志雄, 等. 哨兵-2号光学影像地表形变监测: 以2016年M_W7.8新西兰凯库拉地震为例[J]. 测绘学报, 2019, 48(3): 339-351.
HE Li-jia, FENG Guang-cai, FENG Zhi-xiong, et al. Coseismic displacements of 2016 M_W7.8 Kaikoura, New Zealand earthquake, using Sentinel-2 optical images[J]. Acta Geodaetica et Cartographica Sinica, 2019, 48(3): 339-351 (in Chinese).
[4] Shi X H, Wang Y, Jing L Z, et al. How complex is the 2016 M_W7.8 Kaikoura earthquake, South Island, New Zealand?[J]. Science Bulletin, 2017, 62(5): 309-311.
[5] Cesca S, Zhang Y, Mouslopoulou V, et al. Complex rupture process of the M_W7.8, 2016, Kaikoura earthquake, New Zealand, and its aftershock sequence[J]. Earth and Planetary Science Letters, 2017, 478: 110-120.
[6] Wang T, Wei S J, Shi X H, et al. The 2016 Kaikōura earthquake: Simultaneous rupture of the subduction interface and overlying faults[J]. Earth and Planetary Science Letters, 2018, 482: 44-51.
[7] 周云, 王卫民, 熊林, 等. 2014年2月12日M_W6.9于田地震震源破裂过程及对周围断层的应力影响[J]. 地球物理学报, 2015, 58(1): 184-193.
ZHOU Yun, WANG Wei-min, XIONG Lin, et al. Rupture process of 12 February 2014, Yutian M_W6.9 earthquake and stress change on nearby faults[J]. Chinese Journal of Geophysics, 2015, 58(1): 84-193 (in Chinese).
[8] 梁洪宝, 武艳强, 陈长云, 等. 2014年新疆于田M_S7.3地震同震位移及位错反演研究[J]. 地球物理学报, 2018, 61(12): 4817-4826.
LIANG Hong-bao, WU Yan-qiang, CHEN Chang-yun, et al. Coseismic displacement and dislocation inversion of 2014 Yutian M_S7.3 earthquake in Xinjiang[J]. Chinese Journal of Geophysics, 2018, 61(12): 4817-4826 (in Chinese).
[9] 罗旭巍, 孙建宝, 沈正康, 等. 基于InSAR同震形变观测反演2010年新西兰南岛M_W7.1 Darfield地震同震破裂分布[J]. 地球物理学报, 2013, 56(8): 2613-2624.
LUO Xu-wei, SUN Jian-bao, SHEN Zheng-kang, et al. Co-seismic slip distribution of 2010 Darfield, New Zealand M_W7.1 earthquake inverted using InSAR measurements[J]. Chinese Journal of Geophysics, 2013, 56(8): 2613-2624 (in Chinese).
[10] Langridge R M, Campbell J, Hill N, et al. Paleoseismology and slip rate of the Conway Segment of the Hope Fault at Greenburn Stream, South Island, New Zealand[J]. Annals of Geophysics, 2003, 46(5): 1119-1139.
[11] 程惠红, 张贝, 张怀, 等. 2016年11月13日新西兰凯库拉(Kaikoura)M_W7.8地震同震位移和应力数值分析[J]. 地球物理学报, 2017, 60(7): 2641-2651.
CHENG Hui-hong, ZHANG Bei, ZHANG Huai, et al. Calculation of the co-seismic deformation and stress changes of the Kaikoura M_W7.8 earthquake, Nov 13, 2016[J]. Chinese Journal of Geophysics, 2017, 60(7): 2641-2651 (in Chinese).
[12] 韩竹军, Nicola Litchfield, 冉洪流, 等. 新西兰2016年凯库拉M_W7.8地震地表破裂带特征初析[J]. 地震地质, 2017, 39(4): 675-688.
HAN Zhu-jun, Nicola Litchfield, RAN Hong-liu, et al. Primarily study on features of surface ruptures induced by the 2016 M_W7.8 Kaikoura earthquake, New Zealand[J]. Seismology and Geology, 2017, 39(4): 675-688 (in Chinese).
[13] Xu W B, Feng G C, Meng L S, et al. Transpressional rupture cascade of the 2016 M_W7.8 Kaikoura earthquake, New Zealand[J]. Journal of Geophysical Research: Solid Earth, 2018, 123(3): 2396-2409.
[14] Ulrich T, Gabriel A A, Ampuero J P, et al. Dynamic viability of the 2016 M_W7.8 Kaikōura earthquake cascade on weak crustal faults[J]. Nature Communications, 2019, 10: 1213.
[15] Duputel Z, Rivera L. Long-period analysis of the 2016 Kaikoura earthquake[J]. Physics of the Earth and Planetary Interiors, 2017, 265: 62-66.
[16] Langridge R M, Ries W F, Litchfield N J, et al. The New Zealand active faults database[J]. New Zealand Journal of Geology and Geophysics, 2016, 59(1): 86-96.
[17] Litchfield N J, Van Dissen R, Sutherland R, et al. A model of active faulting in New Zealand[J]. New Zealand Journal of Geology and Geophysics, 2014, 57(1): 32-56.
[18] Hollingsworth J, Ye L L, Avouac J P. Dynamically triggered slip on a splay fault in the M_W7.8, 2016 Kaikoura (New Zealand) earthquake[J]. Geophysical Research Letters, 2017, 44: 3517-3525.
[19] Fu G Y, Sun W K. Effects of spatial distribution of fault slip on calculating co-seismic displacement: Case studies of the Chi-Chi earthquake (M_W7.6) and the Kunlun earthquake (M_W7.8)[J]. Geophysical Research Letters, 2004, 31: L2160.
[20] 邵志刚, 马宏生, 张浪平, 等. 2010年玉树M_S7.1地震同震破裂、余震分布特征及其与构造的关系[J]. 地球物理学报, 2013, 56(11): 3800-3810.
SHAO Zhi-gang, MA Hong-sheng, ZHANG Lang-ping, et al. The characteristics of co-seismic slip and aftershocks distribution of the M_S7.1 earthquake at Qinghai Yushu in 2010 and its relationship with tectonics[J]. Chinese Journal of Geophysics, 2013, 56(11): 3800-3810 (in Chinese).
[21] Du Y J, Segall P, Gao H J. Dislocation in inhomogeneous media via a moduli perturbation approach: General formulation and two-dimensional solutions[J]. Journal of Geophysical Research: Solid Earth, 1994, 99(B7): 13767-13779.
[22] Savage J C. Displacement field for an edge dislocation in a layered half-space[J]. Journal of Geophysical Research: Solid Earth, 1998, 103(B2): 2439-2446.
[23] Cattin R, Briole P, Lyon-Caen H, et al. Effects of superficial layers on coseismic displacements for a dip-slip fault and geophysical implications[J]. Geophysical Journal International, 1999, 137(1): 149-158.
[24] Hearn E H, Burgmann R, Reilinger R E. Dynamics of Izmit earthquake postseismic deformation and loading of the Duzce earthquake hypocenter[J]. Bulletin of the Seismological Society of America, 2002, 92(1): 172-193.
[25] Wang R J, Diao F Q, Hoechner A. SDM-A geodetic inversion code incorporating with layered crust structure and curved fault geometry[C]. EGU General Assembly, 2013, 15: EGU2013-2411-1.
[26] 陈威, 乔学军, 刘刚, 等. 基于GNSS与InSAR约束的九寨沟M_S7.0地震滑动模型及其库仑应力研究[J]. 地球物理学报, 2018, 61(5): 2122-2132.
CHEN Wei, QIAO Xue-jun, LIU Gang, et al. Study on the coseismic slip model and Coulomb stress of the 2017 Jiuzhaigou M_S7.0 earthquake constrained by GNSS and InSAR measurements[J]. Chinese Journal of Geophysics, 2018, 61(5): 2122-2132 (in Chinese).
[27] 陈树, 董彦芳, 洪顺英, 等. 2016年新疆阿克陶M_S6.7地震同震形变特征和层滑动分布反演[J]. 地震, 2018, 38(3): 81-89.
CHEN Shu, DONG Yan-fang, HONG Shun-ying, et al. Co-seismic deformation field and inversion of fault slip distribution of the 2016 Aketao M_S6.7 earthquake[J]. Earthquake, 2018, 38(3): 81-89 (in Chinese).
[28] 屠泓为, 汪荣江, 刁法启, 等. 运用SDM方法研究2001年昆仑山口西M_S8.1地震破裂分布: GPS和InSAR联合反演的结果[J]. 地球物理学报, 2016, 59(6): 2103-2112.
TU Hong-wei, WANG Rong-jiang, DIAO Fa-qi, et al. Slip model of the 2001 Kunlun mountain M_S8.1 earthquake by SDM: joint inversion from GPS and InSAR data[J]. Chinese Journal of Geophysics, 2016, 59(6): 2103-2112 (in Chinese).
[29] 申文豪, 李永生, 焦其松, 等. 联合强震记录和InSAR/GPS结果的四川九寨沟7.0级地震震源滑动分布反演及其地震学应用[J]. 地球物理学报, 2019, 62(1): 115-129.
SHEN Wen-hao, LI Yong-sheng, JIAO Qi-song, et al. Joint inversion of strong motion and InSAR/GPS data for fault slip distribution of the Jiuzhaigou 7.0 earthquake and its application in seismology[J]. Chinese Journal of Geophysics, 2019, 62(1): 115-129 (in Chinese).
[30] 黄星, 洪顺英, 金红林, 等. 2015年新疆皮山M_W6.4地震发震断层和滑动分布反演[J]. 地震, 2020, 40(1): 84-98.
HUANG Xing, HONG Shun-ying, JIN Hong-lin, et al. Inversion of the seismogenic fault and fault slip distribution of the 2015 Pishan M_W6.4 earthquake[J]. Earthquake, 2020, 40(1): 84-98 (in Chinese).
[31] 庄春晓, 王仕祥, 王仲想, 等. 九寨沟M_S7.0地震的同震形变场误差研究及断层滑动分布反演[J]. 测绘与空间地理信息, 2020, 43(3): 211-214+224.
ZHUANG Chun-xiao, WANG Shi-xiang, WANG Zhong-xiang, et al. Study on error of coseismic deformation field and inversion of fault slip distribution of the Jiuzhaigou M_S7.0 earthquake[J]. Geomatics & Spatial Information Technology, 2020, 43(3): 211-214+224 (in Chinese).
[32] Wang R J, Parolai S, Ge M R, et al. The 2011 M_W9.0 Tohoku earthquake: Comparison of GPS and strong-motion data[J]. Bulletin of the Seismological Society of America, 2013, 103(2B): 1336-1347.
[33] Ali S T, Freed A M, Calais E, et al. Coulomb stress evolution in Northeastern Caribbean over the past 250 years due to coseismic, postseismic and interseismic deformation[J]. Geophysical Journal International, 2008, 174(3): 904-918.
[34] Jager J C, Cook N G W, Zimmerman R W. Fundamentals of rocks mechanics[M]. Oxford: Blackwell Publishing, 2007.
[35] Harris R A. Introduction to special section: Stress triggers, stress shallows, and implications for seismic hazard[J]. Journal of Geophysical Research, 1998, 103(B10): 24347-24358.
[36] 盛书中, 万永革, 蒋长胜, 等. 2015年尼泊尔M_S8.1强震对中国大陆静态应力触发影响的初探[J]. 地球物理学报, 2015, 58(8): 1834-1842.
SHENG Shu-zhong, WAN Yong-ge, JIANG Chang-sheng, et al. Preliminary study on the static stress triggering effects on China mainland with the 2015 Nepal M_S8.1 earthquake[J]. Chinese Journal of Geophysics, 2015, 58(8): 1834-1842 (in Chinese).
[37] 徐晶. 鲜水河断裂带的构造应力加载与强震间相互影响研究[D]. 北京: 中国地震局地震预测研究所, 2013.
XU Jing. Tectonic loading and the interaction among the large earthquake on Xianshuihe Fault[D]. Beijing: Institute of Earthquake Science, China Earthquake Administration, 2013 (in Chinese).
[38] Wang R J, Lorenzo-Martin F, Roth F. PSGRN/PSCM—A new code for calculating co- and post-seismic deformation, geoid and gravity changes based on the viscoelastic-gravitational dislocation theory[J]. Computers and Geosciences, 2008, 32(4): 527-541.
[39] Freed A M. Earthquake triggering by static, dynamic, and postseismic stress transfer[J]. Annual Review of Earth and Planetary Sciences, 2005, 33: 335-367.
[40] Alder S, Smith S A F, Scott J M. Fault-zone structure and weakening processes in basin-scale reverse faults: The Moonlight Fault Zone, South Island, New Zealand[J]. Journal of Structural Geology, 2016, 91: 177-194.
[41] 陈时军, David Harte, 马丽, 等. 新西兰地区地震活动时空分布的多重分形特征研究[J]. 地震学报, 2003, 25(3): 298-307.
CHEN Shi-jun, David Harte, MA Li, et al. Research on the multifractal characteristics of the temporal-spatial distribution of earthquakes over New Zealand area[J]. Acta Seismologica Sinica, 2003, 25(3): 298-307 (in Chinese).