山东苍山Ms5.2地震泰安石英倾斜仪异常分析

利用矢量曲线、γ因子等方法识别苍山Ｍｓ５．２地震前泰安石英倾斜仪的前兆异常。分析认为：ＳＱ－７０石英倾斜仪反映出一定的地形变异常信息。     

1991年3月26日大同—阳高5.8Ms地震的地壳形变异常

分析了1991年3月26日大同—阳高5.8Ms地震与1989年10月大同—阳高6.1Ms震群的关系,认为这两次地震属于同一类震群.介绍了这次地震前赤城台石英摆倾斜仪、太原台目视水管倾斜仪和阳原台金属摆倾斜仪的异常情况.从两次地壳形变异常的异同映证了两次地震属同一震群.同时也说明利用地壳形变资料预报地震是有希望的.     

山东苍山5.2级地震定点形变异常的识别

利用长趋势异常、矢量曲线、γ因子等方法对泰安、郯城、徐州３个台的７套倾斜仪进行了异常识别，得出泰安ＳＱ—７０石英倾斜仪、徐州ＳＱ—７０石英倾斜仪反映了山东苍山５．２级地震异常信息的结论。     

潮汐偏角法在地震预报中的应用研究

应用潮汐偏角法对山东泰安、马陵山、烟台３个台的石英摆倾斜仪、自记水管倾斜仪资料进行了分析处理,结果显示：泰安、马陵山分点潮汐偏角在华北各次５．０级以上地震,特别是黄海地震前１年７个月至１个月时段内出现的高值或低值异常,表明潮汐偏角可应用于地震中短期预报。     

1998年8月伽师6.0级、6.6级地震前阿合奇台和乌什台地倾斜异常

引言１９９８年８月２日伽师６．０级、８月２７日６．６级地震前,位于震中２８０ｋｍ东北方向的阿合奇地震台和乌什地震台的地倾斜资料均出现了不同程度的前兆异常。尤其是阿合奇台的地倾斜,在两次地震前异常特点明显。笔者应用“八五”攻关成果软件,对这两次地震进行了跟踪分析研究,并对１９９８年８月２７日６．６级地震作出了地震“三要素”预报。１　阿合奇台地倾斜异常阿合奇地震台ＳＱ－７０Ｂ型石英水平摆倾斜仪于１９８９年开始投入观测,历年来记录较稳定,对其周围发生的较大地震均有较好的异常对应。１．１　日均值分量异常…     

永胜倾斜潮调和分析结果及其与地震的关系

本文利用永胜台水管倾斜仪观测资料分别进行了资料长度为１月和１年的维尼迪科夫调和分析。研究了振幅因子与地震的关系，发现地震前ＥＷ２分量Ｍ２波与ＮＳ分量Ｏ１波的γ值具有不同程序的异常变化，异常量为１．５％－７．７％；在地震发生前或地震发生时，各个主潮波γ值误差变大。用震例分析证明了倾斜固体潮振幅异常用于地震预报的可行性。     

随州-信阳ML4.2地震前定点形变异常特征

分析了2000年1月28日随州和信阳交界处发生的ML4．2地震前，信阳地震台（△＝35km)定点形变中短期及临震异常特征。分析研究表明：该次地震前信阳台目视水管倾斜仪EW向测值从1999年6开始出现反向变化，NS向测值从1999年3月开始出现加速变化；水平摆倾余仪EW向和NS向测值分别从1999年2月和1999年6月开始出现反向变化。这些异常于2000年下半年结束。震前3天水管倾斜仪EW向测值出现加速变化；震前5－8天NS向测值除了出现加速变化外，还出现突跳。城前约20天，水平摆倾斜仪2个方向测值构出现了准周期性波动变化。另外，形变固体潮潮汐因子也有明显异常。     

张北6.2级地震前宝昌地震台的前兆异常研究

１９９８年１月１０日河北省张北６．２级地震前,距震中１００ｋｍ的内蒙古宝昌地震台石英倾斜仪ＮＳ分量自１９９６年７月出现向南倾斜的趋势异常,ＥＷ分量１９９７年８月向西倾斜的短期异常,并在地震发生前６天之内,倾斜仪固体潮曲线上出现多次阶跃式畸变,可能是张北６．２级地震的临震前兆。与此同时,该台站的地电阻率也在震前２．５个月出现短期异常。     

固体潮调和分析及效能评价

本文选择四川省条件较好的台站的摆式倾斜仪。水管倾义、石英伸缩仪１９８７年以来的固体潮观测资料,采用Ｖｅｎｅｄｉｋｏｖ调和分析方法处理,提取各台倾斜固体潮、硐体应变固体潮全日波（Ｑ１波）和半日波（Ｍ２波）的潮汐因子γ、α值及相位滞后因子△Ψ值,分析其在中强地震前的变化特点,探索地震前兆异常 。     

银川台石英摆倾斜仪异常特征及预测指标分析

应用形态法、潮汐因子判别法对银川台石英摆倾斜仪观测资料进行系统分析,拟总结出银川台石英摆倾斜仪观测资料异常特征及其预测指标。分析结果显示:在银川台周边地区400km范围内发生的中强地震前,银川台石英摆倾斜仪观测资料存在明显的异常,同时在2001年昆仑山口西8.1级地震、2008年四川汶川8.0级地震前均存在不同程度的异常变化。     

Analysis on the Characteristics of the Kalpin MS5.3 Earthquake Sequence of December 1, 2013 and Anomalies before the Earthquake

This paper introduces the basic parameters, focal mechanism solutions and earthquake sequence characteristics of the Kalpin M_S5.3 earthquake sequence of December 1, 2013, and analyzed seismic activity before the earthquake, the adjacent tectonic features and the precursory anomaly at fixed points within a range of 200km. Research indicates:(1) The earthquake occurred on Kalpin fault, the source rupture type is thrust faulting with sinistral strike-slip component. (2) The earthquake sequence is mainshock-aftershock type, with the aftershock distribution attenuating quickly and trending NE. (3) Abnormal seismic activity before the earthquake was characterized by seismically nesting quiescence of M_S2.0-4.0 earthquakes, seismic quiescence of M_S4.0 earthquakes and seismic belts of M_S3.0 earthquakes in the Kalpin block, abnormal enhancement zone of moderate earthquakes on Puchang fault and seismological parameters. (4) Anomalies of precursory observation data at fixed stations are mainly characterized by mutation. Apart from the borehole tiltmeter in Halajun, the spatial distribution of other abnormal precursors showed a phenomenon of migration from the near field to far field and from the epicenter to the peripheries.     

Geomagnetic diurnal-variation anomalies and their relation to strong earthquakes

The diurnal-variation anomalies of the vertical-component in geomagnetic field are mainly the changes of phase and amplitude before strong earthquakes. On the basis of data recorded by the network of geomagnetic observatories in China for many years, the anomalous features of appearance time of the minima of diurnal variations (i.e, low-point time) of the geomagnetic vertical components and the variation of their spatial distribution (i.e, phenomena of low-point displacement) have been studied before over 30 strong earthquakes with M _S≥6.6 such as Kunlunshan M _S=8.1 earthquake on November 14, 2001; Bachu-Jashi M _S=6.8 earthquake on February 24, 2003; Xiaojin M _S=6.6 earthquake on September 22, 1989, etc. There are good relations between such rare phenomena of geomagnetic anomalies and the occurrence of earthquakes. It has been found that most earthquakes occur in the vicinity of the boundary line of sudden change of the low-point displacement and generally within four days before and after the 27th or 41st day counting from the day of appearance of the anomaly. In addition, the anomalies of diurnal-variation amplitude near the epicentral area have been also studied before Kunlunshan M _S=8.1 earthquake and Bachu-Jiashi M _S=6.8 earthquake. Foundation item: National Science Technology Tackle Key Project during the Tenth Five-year Plan (2001BA601B01-05-04)     

2017年3月27日漾濞5.1级地震前后气枪震源观测走时数据的变化

以2017年3月27日漾濞5.1级地震为例,根据区域特性和信噪比要求,选取数据较为完整的6个台站记录的2017年1月1日～6月6日期间的宾川地震信号发射台气枪震源波形资料,采用互相关检测技术提取6个台站各自稳定震相的走时数据,并对漾濞5.1级地震前后走时数据的变化情况进行分析。结果表明,漾濞5.1级地震前后6个台站各自稳定震相存在较为明显的走时变化,且短期内走时变化具有较好的同步性,相关台站异常幅度大小和异常出现时间存在细小差异。地震发生前,6个台站走时低值异常过程明显,以YUL台最为显著。地震发生前后走时变化形态特征为双“V”型,漾濞5.1级地震发生在第1个“V”型末端。地震发生后,不同方位相关台站受地震的影响程度不同,走时波动大小存在差异。     

Seismicity anomalies before the great earth—quake of Ms=8.1 in the Kunlun Pass and its significance to earthquake prediction

A great earthquake of M _S=8.1 took place in the west of Kunlun Pass on November 14, 2001. The epicenter is located at 36.2°N and 90.9°E. The analysis shows that some main precursory seismic patterns appear before the great earthquake, e.g., seismic gap, seismic band, increased activity, seismicity quiet and swarm activity. The evolution of the seismic patterns before the earthquake of M _S=8.1 exhibits a course very similar to that found for earthquake cases with M _S≥7. The difference is that anomalous seismicity before the earthquake of M _S=8.1 involves in the larger area coverage and higher seismic magnitude. This provides an evidence for recognizing precursor and forecasting of very large earthquake. Finally, we review the rough prediction of the great earthquake and discuss some problems related to the prediction of great earthquakes.     

按震兆共迁法以平凉远台地电前兆异常回顾性讨论2017年九寨沟大震的预测

2017年九寨沟7级大震前平凉台上的短临地电阻率异常甚为明显,平凉距九寨沟震中360 km。如此远的震中距离只能用"震兆共迁法"预测九寨沟大震震中。     

青藏高原北部地区地震窗口特征及其预报意义

利用青藏高原北部地区弱震活动资料筛选出3个具有中短期预报效能的地震窗口,分析了Ms≥5．0地震前各个窗口的异常特征,提取出半定量的中短期预报指标．即：在中强地震前80％的异常出现在地震前1～6个月,以中心异常出现时间向后推1～6个月作为预测的发震时间;异常幅度与未来震级之间没有明显的对应关系．对于7级以上大地震,古浪窗的显异常主要对应边界水平剪切走滑活动断裂上发生的地震;舟曲窗和乌海窗的显异常主要对应活动块体内部挤压逆冲断裂上发生的地震．而5～6级的中等地震没有明显的对应规律．     

Investigation of rupture process of the 1999 M =5.4 Xiuyan, Liaoning, earthquake sequence

Conclusions The sequence of the November 29, 1999 Xiuyan, Liaoning, earthquake withM _S=5.4 is relocated, and its rupture process is analyzed. Results are as follows: The rupture extended mainly before the January 12, 2000,M _S=5.1 earthquake. There are two phases of rupture extending: The first phase was before the November 29, 1999,M _S=5.4 earthquake, epicenters were situated within a small region with a dimension of about 5 km, and the focal depth increased. It shows that the rupture mainly extended from shallow part to deep in the vertical direction. The second phase was between theM _S=5.4 earthquake and theM _S=5.1 earthquake, earthquakes migrated along southeast, the focal depth decreased. It indicates that the rupture extended along southeast and from deep to shallow part. Foundation item: The Project of “Mechanism and Prediction of the Strong Continental Earthquake” (95-13-05-04). Contribution No. 01FE2017, Institute of Geophysics, China Seismological Bureau.     

对2017年九寨沟MS7.0地震的预测分析

2017年8月8日四川九寨沟发生M_S7.0地震。震前我们实验室主要做出以下预测：（1）根据我国强震的空间分布有序性规律,在2015年曾做出预测：甘肃省东南部、四川交界处将来可能会发生8级地震;（2）根据44年周期和7年周期,2016年预测四川区域在2017年会有7.5级地震发生;（3）依据地磁仪器观测到的数据异常,2017年7月28日认为近期将有6~7级地震发生。九寨沟地震发生后,经综合分析我们的三次预测,以及6—7月在四川茂县出现的多次滑坡事件,认为若将这些因素结合起来,将会是一个很好的短临预测方式。     

昆仑山口西8.1级地震前的地震活动异常及预测意义的讨论

昆仑山口西8．1地震前明显地出现大区域地震活动平静、高6值、高调制、低锅值的异常配套现象．回顾性分析了巨大地震前不同时问和空间尺度的地震活动性异常,探讨了巨大地震的预测可能性。