台湾南投地震(M_S6.7)短期预测、中期预测和流变构造分析

Short-term and medium-term prediction and rheo-tectonic analysis for Nantou earthquake (M_S6.7)

回顾了不同方法对于台湾南投（MS6.7）地震的成功中期预测和短期预测,分析了南投地震的构造背景及发震机制。根据太阳黑子数为主要参数的太阳活动度分析,曾小苹和林云芳于2013年4月预测2013年台湾高雄—南投—花莲一带,将发生MS7.0地震。2013年5月12日,沈宗丕和林命周根据＂磁暴月相二倍法＂做了一个短期和临震预测：2013年6月19日前后5天或10天左右,台湾省或邻近海域在内的地震带可能发生一次MS7.5~8.0级左右的大地震。2013年5月26日,张建国向部分专家通报了基于他自创的全球地震天象干支序列预测图谱做出的中期预测：发震时间为2013年4月24日—2014年2月10日（高危时区为阴历4—5月）;预测地区为嘉义—台南—南投—云林（23.0°~23.4°~24.0°N,120.0°~120.6°~121.2°E）;预测震级为MS6.2~6.6~7.2。利用地震云和云地映对分析和陈界宏的磁异常交点,2013年5月26日23：55,重庆万州吴达兵预测在2013年6月中旬以前台湾云地映对地区（24°±0.2°N,121°±0.2°E）将发生ML6.2±0.4地震。2013年5月27日,黄建文明确发出台湾南投应力集中警报;5月29日,又发布强应力集中持续增强特别警报。2013年6月2日13：43,台湾南投（23.87°N,121.00°E）发生MS6.7（ML6.3）地震,震源深度9km。发震时间落入吴达兵的短期预测区间;落入张建国的高危时区（阴历4—5月）;比沈宗丕和林命周预测的短期预测时间范围提前7天;分别落入曾小苹和林云芳的中期预测范围。震中位置与吴达兵的预测完全一致;与陈界宏磁异常交点基本一致;准确落入张建国的预测区间;与曾小苹和林云芳的预测地区一致。震级与吴达兵的预测震级高度一致;落入张建国的中期预测范围;与曾小苹和林云芳的震级预测基本一致。经过对比可以看出,吴达兵的短期预测、张建国的中期预测、曾小苹和林云芳的中期预测都是成功的。沈宗丕和林命周的时间预测是基本成功的。构造分析、震源机制解和卫星重力异常分析结果表明：屈尺—潮州逆冲断裂是南投地震发震构造;南投地震的发生与菲律宾板块向NWW入欧亚板块中下地壳并使台湾中央山脉向其西侧台湾海峡盆地逆冲有关,是卫星重力异常梯度带或地壳密度陡变带边缘与盆山边界断裂带交汇处积累的能量突然释放的结果。

This article reviews the successful short-term and medium-term earthquake predictions for the Nantou earthquake（MS6.7）and analyzes its tectonic background and occurring mechanism.According to the analysis of the solar activity taking the sunspot number as the main factor,Zeng Xiaoping and Lin Yunfang predicted that a MS7.0earthquake will occur in the Gaoxiong-Nantou-Hualian area of Taiwan in 2013in their article printed in April,2013.On May 12,2013,Shen Zongpi and Lin Mingzhou made a short-term and imminent prediction on the basis of the two-time method of magnetic storm related to lunar phase,that there would be a MS7.0-8.0big earthquake occurring along the earthquake zone including Taiwan and its adjacent waters in 5or 10days before or after June 19,2013.On May 26,2013,Zhang Jianguo informed some experts about his medium-term prediction for an earthquake,that the occurring time would be in the period between April 24,2013and February 10,2014（the high risk period would be in the fourth and fifth lunar month）,that the earthquake area would be in Jiayi-Tainan-Nantou-Yunlin（23.0°-23.4°-24.0°N,120.0°-120.6°-121.2°E）,and the magnitude would be MS6.2-6.6-7.2.On the basis of the analysis of the earthquake cloud,the correspondence between cloud and ground and the intersection point of magnetic anomalies,Wu Dabing predicted that there would be an earthquake with magnitude of ML6.2±0.4 occurring in Taiwan（24°±0.2°N,121°±0.2°E）before the midmonth of June,2013.On May 27,2013,Huang Jianwen raised the alarm that the stresses were concentrating in Nantou county of Taiwan.On May 29,he further raised the special alarm that intensive stresses were continuously concentrating.At 12：34of June 2,2013,aMS6.7（ML6.3）earthquake occurred in Nantou of Taiwan with the epicenter at（23.87°N,121.00°E）and the focus at the depth of 9km.It occurred in the short-term prediction period made by Wu Dabing,in the high risk period of the fourth and fifth month predicted by Zhang Jianguo,7days ahead of the short-term period predicted by ShenZongpi and Lin Mingzhou and dropped into the medium-term prediction period made by Zeng Xiaoping and Lin Yunfang,respectively.The epicenter corresponds with the predicted location of Wu Dabing,is basically the same with the intersection of the magnetic anomalies,and drops into the predicted region of Zhang Jianguo and of Zeng Xiaoping and Lin Yunfang.The magnitude corresponds with the prediction of Wu Dabing,drops into the predicted range of Zhang Jianguo,and approaches the value of Zeng Xiaoping and Lin Yunfang.We can see from the comparison above,that the short-term prediction of Wu Dabing,the medium-term prediction of Zeng Xiaoping and Lin Yunfang and of Zhang Jianguo are all successful and that the short-term prediction of Shen Zongpi and Lin Mingzhou is basically successful.The comprehensive analysis of the tectonic background,the focus mechanism solution and the satellite gravity anomalies of 2-638order indicate that the Quchi-Chaozhou fault is the triggering structure and that the Nantou earthquake resulted from the wedging of the Philippine plate into between the middle and lower crust of the Eurasian plate,causing the release of the energy accumulated at the intersection of the edge of the satellite gravity gradient zone or the crust density gradient zone and the westward thrust boundary fault between the Taiwan Central Mountain and the Taiwan strait basin.