A REVIEW OF THE THINKING AND PROCESS ABOUT PREDICTION OF LUSHAN M7.0 EARTHQUAKE ON APR. 20, 2013

doi:10.3969/j.issn.0253-4967.2014.04.012

Abstract

Abstract:

Before the Lushan M7.0 earthquake of April 20, 2013, fault displacement time histories inferred from near-field observation in Xianshuihe, Anninghe and Zemuhe Fault zones in Sichuan Province showed long-, mid-, and short-term anomalies which deviated from the normal background. The long-term anomalies were mainly represented by extensional faulting, the mid-term anomalies were marked mainly by turning of anomaly trends, and the short-term anomalies appeared mainly as compressional movement of the central-northern segment of Xianshuihe Fault. And based on these anomalies, a relatively accurate short-term prediction to this earthquake was proposed by the Survey Engineering Institute of Earthquake Administration of Sichuan Province. In this article, we summarize the thoughts and process of the prediction to Lushan earthquake, and present the bases and process for the long-, mid-, and short-term prediction. This experience can be useful for short-term prediction of strong earthquake in the future. Our preliminary results show that: 1)The sudden acceleration of variation in anomaly of short-baseline and short-leveling has short-term predictive significance to the origin time of strong earthquake. 2)Combined with analysis on the characteristics of time series of the occurrence time of cross-fault deformation anomalies, and the high gradient zones and their temporal evolutions revealed by mobile gravity surveys, we chose the intersection of the anomalous zones as the hazardous area and found it has a better predictive effect for determining the location of strong earthquake. 3)Statistical analysis shows that the duration of cross-fault deformation anomalies has certain significance for predicting the magnitude of strong earthquake. According to the characteristics of fault activity, the southeastward movement rate of the Bayar Har block may be greater than that of the eastern boundary of the Sichuan-Yunnan block before the Lushan earthquake, which aggravated the compressional and extensional movement of the northern segment of Longmenshan Fault, the middle-northern segment of Xianshuihe Fault and the Zemuhe Fault, and made the southern segment of Longmenshan Fault and the northern segment of Anninghe Fault locked. The faults differed remarkably in their activity patterns, which were mutually restrained and adjusted, as well as convertible. Thus, brittle rocks in the transition zone between plateau and basin ruptured and earthquake occurred. Currently, short-term earthquake prediction is still based on empirical results, and its scientificity is insufficient and pending further discussion.

Key words: near-field fault displacement, mobile gravity, Lushan earthquake, prediction review

摘要：

2013年 "4.20"芦山7.0级地震前, 四川跨断层形变资料在紧邻发震断裂的鲜水河、安宁河、则木河断裂带上出现了偏离正常背景的长、中、短期异常, 长期异常以断层张性活动为主, 中短期以趋势转折为主, 短期则以鲜水河中北段压性活动为主, 且据此做出了较准确的短期预测.文中将对该次地震的预测思路及过程进行回顾, 展示长、中、短期预测依据及过程, 为未来强震的短期预测总结经验.分析结果认为:1)跨断层短水准、短基线的突变加速异常对强震发生的时间有着较好的短期预测意义;2)综合利用跨断层前兆异常出现的时序特征、流动重力高梯度带及差异性变化进行分析, 提取其异常交会部位, 对强震的发生地点有着较好的预测效果;3)跨断层形变异常持续时间的统计对于强震发生的震级有一定的指示意义;从断层活动特性来看, "4.20"芦山地震前, 巴颜喀拉块体向SE的运动速率可能大于川滇块体东边界, 导致龙门山北段、鲜水河中北段、则木河断裂带断层挤压推拉活动加剧, 龙门山南段、安宁河北段 "闭锁", 各个断层活动方式产生明显差异, 但又相互牵制、相互调整, 并在运动形式上相互转换, 从而使高原与盆地过渡地带的脆性岩层产生破裂, 发生强震.

关键词: 跨断层形变, 流动重力, 芦山地震, 预测回顾

CLC Number:

P315.75

SU Qin, YANG Yong-lin, ZHENG Bing, WANG Shuang-hong, LI Fei-fei, LIU Guan-zhong. A REVIEW OF THE THINKING AND PROCESS ABOUT PREDICTION OF LUSHAN M7.0 EARTHQUAKE ON APR. 20, 2013[J]. SEISMOLOGY AND GEOLOGY, 2014, 36(4): 1077-1093.

苏琴, 杨永林, 郑兵, 王双洪, 李菲菲, 刘冠中. 4 ·20芦山7.0级地震预测思路及过程回顾[J]. 地震地质, 2014, 36(4): 1077-1093.

References

程式, 罗灼礼, 任昭明, 等. 1989. 四川地区综合预报判据和指标的研究［J］. 四川地震, (3):70—83.
CHENG Shi, LUO Zhuo-li, REN Zhao-ming, et al. 1989. Research on criterions and indexes of comprehensive prediction in Sichuan region ［J］. Earthquake Research in Sichuan, (3):70—83(in Chinese).
江在森, 丁平, 王双绪, 等. 2001. 中国西部大地形变监测与地震预测［M］. 北京:地震出版社.
JIANG Zai-sen, DING Ping, WANG Shuang-xu, et al. 2001. Geodetic Deformation Monitoring and Earthquake Prediction in Western China ［M］. Seismological Press, Beijing(in Chinese).
吕弋培. 1994. 跨断层地形变测量资料的处理和中短期异常识别［A］. 见:四川中短期地震预测研究. 成都:成都地图出版社. 56—65.
LÜ Yi-pei. 1994. Processing of fault-crossing crustal deformation measurement data and identification of mid- to short-term anomaly［A］. In: Mid- to Short-term Earthquake Prediction Research in Sichuan Region. Chengdu Map Press, Chengdu. 56—65(in Chinese).
吕弋培, 廖华, 苏琴. 1999. 形变测量预报方法及效能评价［J］. 四川地震, 135(1-2): 54—65.
LÜ Yi-pei, LIAO Hua, SU Qin. 1999. Deformation surveying methods and their efficiency evaluation in earthquake prediction ［J］. Earthquake Research in Sichuan, 135(1-2): 54—65(in Chinese).
马瑾, Sherman S I, 郭彦双. 2012. 地震前亚失稳应力状态的识别:以5°拐折断层变形温度场演化的实验为例［J］. 中国科学, 42(5):633—645.
MA Jin, Sherman S I, GUO Yan-shuang. 2012. Identification of meta-instable stress state based on experimental study of evolution of the temperature field during stick-slip instability on a 5° bending fault ［J］. Science in China(Ser D), 55(6): 869—881.
马瑾, 刘力强, 马胜利. 1999. 断层几何与前兆偏离［J］. 中国地震, 15(2):105—115.
MA Jin, LIU Li-qiang, MA Sheng-li. 1999. Fault geometry and departure of precursors from the epicenter ［J］. Earthquake Research in China, 15(2): 105—115(in Chinese).
牛安福. 2007. 地壳形变观测与地震前兆一般性问题的讨论［J］. 国际地震动态, 390(6):43—47.
NIU An-fu. 2007. Some problems on the ground deformation measurements and earthquake precursors ［J］. Recent Developments in World Seismology, 390(6): 43—47(in Chinese).
阮祥, 程万正, 杜方, 等. 2010. 汶川8.0级地震前后四川及邻区构造应力场研究［J］. 中国地震, 26(2):183—191.
RUAN Xiang, CHENG Wan-zheng, DU Fang, et al. 2010. Research on the tectonic stress field in Sichuan and its adjacent areas before and after the Wenchuan M_S 8.0 earthquake ［J］. Earthquake Research in China, 26(2): 183—191(in Chinese).
苏琴, 杨永林, 王兰, 等. 2012a. 鲜水河断裂带跨断层形变中短期强震预测指标研究［J］. 四川地震, 148(4):10—17.
SU Qin, YANG Yong-lin, WANG Lan, et al. 2012a. Study on the strong earthquake predictive indexes from the fault-crossing observation data of mobile crustal deformation measurement along the Xianshuihe Faults ［J］. Earthquake Research in Sichuan, 148(4): 10—17(in Chinese).
苏琴, 杨永林, 向和平, 等. 2012b. 则木河断裂带断层活动特征与中强震关系浅析［J］. 地震研究, 35(1):18—23.
SU Qin, YANG Yong-lin, XIANG He-ping, et al. 2012b. Brief relation analysis between activity feature of Zemuhe Fault and medium-strong earthquakes ［J］. Journal of Seismological Research, 35(1): 18—23(in Chinese).
苏琴, 杨永林, 张永久, 等. 2009. 昆仑山口西8.1级地震对鲜水河断裂断层活动的影响［J］. 地震研究, 32(2):11—15.
SU Qin, YANG Yong-lin, ZHANG Yong-jiu, et al. 2009. Influence of the Kunlun Mountain M_S 8.1 earthquake to the Xianshuihe Fault activity ［J］. Journal of Seismological Research, 32(2): 11—15(in Chinese).
王连捷, 周春景, 孙东生, 等. 2008. 汶川5.12地震引起的库仑应力变化及其对周边地震活动的影响［J］. 地质力学学报, 14(3):193—199.
WANG Lian-jie, ZHOU Jing-chun, SUN Dong-sheng, et al. 2008. Coulomb stress changes caused by Wenchuan earthquake and its influence on seismic activity in the adjacent areas ［J］. Journal of Geomechanics, 14(3): 193—199(in Chinese).
闻学泽, 杜方, 张培震, 等. 2011. 巴颜喀拉块体北和东边界大地震序列的关联性与2008年汶川地震［J］. 地球物理学报, 54(3):706—716.
WEN Xue-ze, DU Fang, ZHANG Pei-zhen, et al. 2011. Correlation of major earthquake sequences on the northern and eastern boundaries of the Bayan Har block, and its relation to the 2008 Wenchuan earthquake ［J］. Chinese J Geophys, 54(3): 706—716(in Chinese).
易桂喜, 闻学泽, 苏有锦. 2008. 川滇地块东边界强震危险性研究［J］. 地球物理学报, 51(6):1719—1725.
YI Gui-xi, WEN Xue-ze, SU You-jin. 2008. Study on the potential strong-earthquake risk for the eastern boundary of the Sichuan-Yunnan active faulted-block, China ［J］. Chinese J Geophys, 51(6): 1719—1725(in Chinese).
张国民, 傅征详, 桂燮泰, 等. 2001. 强地震中短期预报方法及效能评价［M］. 北京:科学出版社.
ZHANG Guo-min, FU Zheng-xiang, GUI Xie-tai, et al. 2001. Strong Earthquake Medium-Short Term Prediction Method and Its Predictive Efficiency Evaluation ［M］. Science Press, Beijing(in Chinese).
中国地震局监测预报司. 2002. 强地震中短期预报方法及其效能研究［M］. 北京:地震出版社.
Department of Earthquake Monitoring and Prediction of China Earthquake Administration. 2002. Research on Medium-Short Term Strong Earthquake Prediction Method and Its Predictive Efficiency ［M］. Seismological Press, Beijing(in Chinese).
祝意青, 闻学泽, 孙和平, 等. 2013. 2013年四川芦山M_S7.0级地震前的重力变化［J］. 地球物理学报, 56(6):1887—1894.
ZHU Yi-qing, WEN Xue-ze, SUN He-ping, et al. 2013. Gravity changes before the Lushan, Sichuan, M_S=7.0 earthquake of 2013 ［J］. Chinese J Geophys, 56(6): 1887—1894(in Chinese).

[1]	CHEN Han-lin, WANG Qin-cai, ZHANG Jin-chuan, LIU Rui-feng. DISCUSSION ON SEISMOGENIC STRUCTURE OF THE JUNE 2022 M_S6.1 EARTHQUAKE AND ITS RELATIONSHIP WITH THE APRIL 2013 M_S7.0 EARTHQUAKE IN LUSHAN, SICHUAN PROVINCE [J]. SEISMOLOGY AND GEOLOGY, 2023, 45(5): 1233-1246.
[2]	MA Si-yuan, XU Chong, CHEN Xiao-li. COMPARISON OF THE EFFECTS OF EARTHQUAKE-TRIGGERED LANDSLIDE EMERGENCY HAZARD ASSESSMENT MODELS: A CASE STUDY OF THE LUSHAN EARTHQUAKE WITH M_W5.8 ON JUNE 1, 2022 [J]. SEISMOLOGY AND GEOLOGY, 2023, 45(4): 896-913.
[3]	FU Ying, HU Bin, ZHAO Min, LONG Feng. PRECISE LOCATION AND SEISMOGENIC STRUCTURE OF THE 2022 LUSHAN M_S6.1 EARTHQUAKE [J]. SEISMOLOGY AND GEOLOGY, 2023, 45(4): 987-1005.
[4]	LIAO Gui-jin, YE Dong-hua, DENG Zhi-hui, LI Chong, TANG Guo-ying, HU Wei-ming. CHARACTERISTICS OF SEISMIC GRAVITY ANOMALY AND GROUND SUBSIDENCE GRAVITY ANOMALY [J]. SEISMOLOGY AND GEOLOGY, 2022, 44(4): 895-908.
[5]	SONG Cheng-ke, ZHANG Hai-yang. ANALYSIS OF COSEISMIC VARIATIONS IN MAGNETIC FIELD OF THE LUSHAN M_S7.0 EARTHQUAKE IN 2013 [J]. SEISMOLOGY AND GEOLOGY, 2020, 42(6): 1301-1315.
[6]	CHEN Zhao-hui, MENG Xiao-hong, ZHANG Shuang-xi, LIU Jin-zhao, WANG Tong-qing, ZHANG Pin, WEI Shao-gang. CHARACTERISTICS OF MULTI-SCALE GRAVITY FIELD VARIATION AND SEISMOGENIC MECHANISM ANALYSIS IN THE SOUTHEASTERN TIBETAN PLATEAU [J]. SEISMOLOGY AND GEOLOGY, 2019, 41(3): 690-703.
[7]	XU Zhi-ping, WANG Fu-yun, JIANG Lei, ZHAO Yan-na, YANG Li-pu, TANG Lin. THE THREE DIMENSIONAL DENSITY STRUCTURE OF CRUST AND UPPER MANTLE IN THE CENTRAL-SOUTHERN PART OF LONGMENSHAN [J]. SEISMOLOGY AND GEOLOGY, 2019, 41(1): 84-98.
[8]	ZENG Di, CHEN Li-chun, CHEN Shun-yun, LI Dong-yu. REANALYSIS OF BEDROCK GROUND TEMPERATURE CHANGES PRIOR TO 2013 LUSHAN M_S7.0 EARTHQUAKE [J]. SEISMOLOGY AND GEOLOGY, 2017, 39(5): 994-1006.
[9]	CHANG Liu, YANG Bo, ZHANG Feng-shuang, XU Ming-yuan, YANG Guo-hua. GPS AND LEVELING CONSTRAINED CO-SEISMIC SOURCE AND SLIP DISTRIBUTION OF THE LUSHAN M_S7.0 EARTHQUAKE ON 20 APRIL 2013 [J]. SEISMOLOGY AND GEOLOGY, 2017, 39(3): 561-571.
[10]	BAI Yu-zhu, XU Xi-wei. ANALYSIS ON THE CHARACTERISTICS OF DURATION AND PERIOD OF GROUND MOTION OF THE LUSHAN EARTHQUAKE BASED ON THE STATION RECORDS [J]. SEISMOLOGY AND GEOLOGY, 2017, 39(1): 92-103.
[11]	WANG Lin, ZHOU Qing-yun, WANG Jun, LI Wen-qiao, ZHOU Lian-qing, CHEN Han-lin, SU Peng, LIANG Peng. THE RESEARCH OF THE SEISMOGENIC STRUCTURE OF THE LUSHAN EARTHQUAKE BASED ON THE SYNTHESIS OF THE DEEP SEISMIC DATA AND THE SURFACE TECTONIC DEFORMATION [J]. SEISMOLOGY AND GEOLOGY, 2016, 38(2): 458-476.
[12]	ZHANG Zhi-wei, ZHOU Long-quan, LONG Feng, RUAN Xiang. SPATIAL AND TEMPORAL CHARACTERISTIC OF STRESS FIELD FOR WENCHUAN M_S8.0 AND LUSHAN M_S7.0 EARTHQUAKE SEQUENCE [J]. SEISMOLOGY AND GEOLOGY, 2015, 37(3): 804-817.
[13]	LIU Li-na, XU Chong, CHEN Jian. DEBRIS-FLOW HAZARD EVALUATION BASED ON GEOMORPHIC INFORMATION ENTROPY AND LANDSLIDE MATERIALS IN THE LUSHAN EARTHQUAKE AFFECTED AREA [J]. SEISMOLOGY AND GEOLOGY, 2015, 37(3): 880-892.
[14]	XIE Tao, ZHENG Xiao-dong, KANG Chun-li, MA Wei-yu, LU Jun. POSSIBLE THERMAL BRIGHTNESS TEMPERATURE ANOMALIES ASSOCIATED WITH THE LUSHAN(CHINA) M7.0 EARTHQUAKE ON 20 APRIL 2013 [J]. SEISMOLOGY AND GEOLOGY, 2015, 37(1): 149-161.
[15]	SHI Lei, JIA Xiao-dong, CHEN Shi, XU Wei-min, LU Hong-yan. GRAVITY CHANGES BEFORE THE LUDIAN, YUNNAN, M_S6.5 EARTHQUAKE OF 2014 AND THE THREE-DIMENSIONAL INVERSION RESEARCH [J]. SEISMOLOGY AND GEOLOGY, 2014, 36(4): 1217-1227.