全国年度地震重点危险区与地震相关性的统计模拟分析

用统计模拟的方法对1990～1997年全国年度重点危险区与地震的相关性进行了分析．由于统计模拟的方法有效地处理了地震和危险区的时空不均匀性,并且得到经运算105 次的统计模拟随机预报概率,将其与实际预报平均概率比较,得到较为客观的结果．结果表明:① 1990～1997年全国年度重点危险区的实际预报平均概率,比完全平均随机划定预报区的统计模拟平均随机概率高0.03719;② 考虑地震活动背景概率时,实际预报平均概率比危险区加权重的统计模拟平均概率高0.02183;③ 将中国大陆依地震分布不均匀性分为新疆西部地区、西南地区和其它地区３个区时,新疆西部地区的实际预报平均概率大大高出统计模拟平均随机概率,其差值为0.20962．      

中国地震学会第六届地震预报专业委员会成立大会暨学术报告会会议纪要

2004年1月3—5日,中国地震学会第六届地震预报专业委员会在北京召开了成立大会暨学术报告会。约50名委员参加了本次会议。会议还特邀本专业委员会顾问中国地震局副局长岳明生和中国地震局地球物理研究所朱传镇教授、中国地震局监测预报司     

ESEP3.0专家系统在新疆年度地震形势预测中的应用检验

使用2000—2003年度新疆地震局震情研究报告中的资料建立异常证据文件，应用ESEP3．0专家系统进行了推理预测，将其中的1年以内的预测意见与这4年新疆“震情研究报告”的预测意见及实际发生的地震情况进行了对比，并按中国地震局制定的“地震预报评分办法”进行了评分，最后认为：ESEP3．0专家系统目前可以用于新疆的年度地震趋势和地震危险区预测。     

新一届亚洲地震委员会(ASC)主席朱传镇研究员简介

亚洲地震委员会(Asian Seismological Commission)第五次大会于2004年10月18—2lEt在亚美尼亚首都埃里温召开。中国地震局地球物理研究所研究员、博士生导师朱传镇当选为新一届亚洲地震委员会主席。俄罗斯的S．Goldin教授当选为第一副主席，越南的Cao Dinh Trien博士当选为第二副主席，印度的R．K．Chadha博士当选为秘书长。     

2004年6月份全球M≥5.0地震动态

根据中国地震局地球物理研究所中国数字地震台网数据管理中心(CDSNDMC)从美国地震学联合研究会数据管理中心(IRISDMC)得到的最新资料,2004年6月份全球范围内共发生M≥5．0地震79次(见表1),其中M5—5．5地震58次,M5．6—6．0地震13次,     

少震弱震省份的年度地震重点危险区的震情监视跟踪工作模式探讨

年度地震重点危险区是指一年内可能发生地震,应强化跟踪、力争作出震前有效预报的地区.通俗的意义指地震发生可能性比较高的地区.一般由中国地震局监测预报司每年年底根据预报专家的年度会商结果划定.     

2004年5月份全球M≥5.0地震动态

根据中国地震局地球物理研究所中国数字地震台网数据管理中心(CDSNDMC)从美国地震学联合研究会数据管理中心(IRISDMC)得到的最新资料,2004年5月份全球范围内共发生M≥5．0地震108次(见表1),其中M5—5．5地震81次,M5．6—6．0地震21次,     

2001年地震震中分布图

为了便于读者了解国内外和邻区以及全球的地震分布图象，本刊每年在第六期上刊登两幅上一年的地震震中分布图．地震资料来源于中国地震局地球物理研究所九室，由陈培善研究员提供． 2001年地震震中分布图     

位于预测区边缘附近的地震统计检验问题

对位于地震预测工作所圈定的地震危险区附近的地震的统计检验问题 ,一直是地震预测研究中一个颇有争议的问题。本文以中国地震局全国年度地震趋势会商的情况为例 ,对这一问题进行了探讨。结果表明 ,将所划定的地震危险区适度扩大 ,即将现有的地震危险区范围向外扩大约 0 5° ,可以显著地提高预测地震的“命中率”。但从统计检验的角度说 ,这样做并不能提高实际地震预测的能力 ,亦即并不能使R值有显著的提高。     

中国地震局监测预报司在北京举办“地震电磁波前兆观测技术与分析预报方法论坛”

为推进地震前兆观测技术和分析预报方法创新,广泛听取各方面对我国地震预报发展的意见和建议,中国地震局监测预报司与中国地震局地球物理研究所、地震预测研究所、中国地震学会电磁专业委员会于2008年11月29—30日在北京联合举办了“地震电磁波前兆观测技术与分析预报方法论坛”。     

Retrospection on the Conclusions of Earthquake Tendency Forecast before the Wenchuan M_S8.0 Earthquake

The reason for the failure to forecast the Wenchuan M_S8.0 earthquake is under study, based on the systematically collection of the seismicity anomalies and their analysis results from annual earthquake tendency forecasts between the 2001 Western Kunlun Mountains Pass M_S8.1 earthquake and the 2008 Wenchuan M_S8.0 earthquake. The results show that the earthquake tendency estimation of Chinese Mainland is for strong earthquakes to occur in the active stage, and that there is still potential for the occurrence of a M_S8.0 large earthquake in Chinese Mainland after the 2001 Western Kunlun Mountains Pass earthquake. However the phenomena that many large earthquakes occurred around Chinese Mainland, and the 6-year long quietude of M_S7.0 earthquake and an obvious quietude of M_S5.0 and M_S6.0 earthquakes during 2002～2007 led to the distinctly lower forecast estimation of earthquake tendency in Chinese Mainland after 2006. The middle part in the north-south seismic belt has been designated a seismic risk area of strong earthquake in recent years, but, the estimation of the risk degree in Southwestern China is insufficient after the Ning’er M_S6.4 earthquake in Yunnan in 2007. There are no records of earthquakes with M_S≥7.0 in the Longmenshan fault, which is one of reasons that this fault was not considered a seismic risk area of strong earthquakes in recent years.     

Research on completeness of earthquake data in the Chinese mainland (II) — The regional distribution of the beginning years of basically complete earthquake data

Based on the concrete conditions of earthquake data in the west of China, East China and South China, we studied the completeness of data in these regions by suitable methods to local conditions. Otherwise, we roughly estimated monitoring capability of local networks in China since 1970 and some outlying regions where the data is lack. Finally, we gave the regional distribution of the beginning years since which the data for different magntiude intervals are largely complete in the Chinese mainland. Contribution No. 94A0050, Institute of Geophysics, SSB, China.     

Comparison of the spatial distribution of ground motion between main shocks and strong aftershocks

Using the ground motion attenuation relation, we calculated and compared the effective peak acceleration (EPA) generated by main shocks and their strong aftershocks of 21 earthquake sequences with MS≥7 occurred in Chinese mainland and offing of China during 1966~2002. The result shows that EPA of strong aftershocks usually exceed that of main shock for 76.2% earthquake sequences and EPA of more than 50% strong aftershocks are greatly lar-ger than that of main shocks in large area, which suggests that it is necessary to take damage produced by strong aftershock into account in the probabilistic seismic hazard analysis and the seismic design.     

Statistical simulation analysis of the correlation between the annual estimated key regions with a certain seismic risk and the earthquakes in China

IntroductionEarthquake prediction is still one of most difficult problems in the world although the researches on it in China have been done for more than 30 years. A lot of experience, however, has been accumulated and some theoretical study on earthquake prediction conducted so that some prediction could be issued prior to earthquakes to obtain real effectiveness of mitigating disasters from these earthquakes to some extent, in China. The annual national consulting convention of earthquake …     

SNR changes of VLF radio signals detected onboard the DEMETER satellite and their possible relationship to the Wenchuan earthquake

Here we used the VLF signal data received by the DEMETER satellite, transmitted from various ground VLF transmitters which are located around China, to study the changes in the signal to noise ratio (SNR) before and after the Wenchuan earthquake, which had a magnitude of 8.0. We also found that the SNRs of different frequency signals decreased significantly over the epicenter region before the earthquake, and reverted to their original levels after the earthquake. This phenomenon may be related to the earthquake. Special Foundation of Basic Research from Institute of Geophysics, China Earthquake Administration (Grant No. DQJB08Z08), National Key Technology R & D Program (Grant No. 2008BAC35B01)     

提高年尺度地震预报成功率的新思路

通过回顾甘肃省近20多年的地震预报工作,发现年尺度地震预报成功率不足8％。分析了年尺度地震预报成功率低下的原因和提高年尺度地震预报成功率在实现具有减灾实效地震预报的目标中的重要意义。最后提出了在对甘肃及邻区地震构造环境、地球物理场和地震资料搜集、整理和分析的基础上,探讨其与强震活动的关联性,寻找地震发生的时、空、强分布规律,建立具有明确构造物理含义的地震预测模型,先进行长期地震危险性分析,再开展年尺度的地震跟踪预报的新思路。沿用这一思路,预期可以减少虚报,进而提高年尺度地震预报成功率。     

青年地震工作者在2008年汶川8.0级地震后科技支撑工作中的作用——对青年科技人员教育和培训的评估和讨论

2008年5月12日汶川8.0级地震发生后,地震科技工作者立即投入到震后应急救援、现场余震监测、灾害评估、地震机理研究、震情趋势判定和现场科学考察中。其中,中国地震局地球物理研究所青年专家在地震精定位、震源机制及数字化地震参数计算、震源破裂过程、地震灾区区划图编制、余震破坏影响范围确定、地震社会学分析与应用等方面发挥了重要作用。截止到2008年12月,研究所40岁以下科技人员在各种科研刊物上发表了SCI、EI文章就有10余篇,参加现场工作人员41人次。青年科技人员能够迅速投入到震后科技支撑工作中,得益于研究所平时对青年科技人员教育和培训工作的重视,本文对此进行了评估和讨论。     

Observation and analysis of geomagnetic abnormity associated with the Ms=5.7 Jiujiang-Ruichang earthquake

A three-component geomagnetic survey was carried out during the period from 2002 to 2004 in China including Jiujiang-Ruichang region. Comparing the ＂2005.0 surface spline model of China geomagnetic field＂ created on the basis of the survey data with the ＂1970.0 surface spline model of China geomagnetic field＂, we can see an obvious abnormity in the geomagnetic horizontal component within a range of about 100 km around the epicenter of the Ms=5.7 Jiujiang-Ruichang earthquake occurred on November 26, 2005. After the earthquake, we carded out a repeated geomagnetic survey at 21 stations in the Jiujiang-Ruichang region and created a corresponding ＂2005.0 partially revised surface spline model of China geomagnetic field＂. By comparing the above three models, analyzing the geomagnetic horizontal component at the profile in the Jiujiang-Ruichang region and quantitatively studying the geomagnetic data of every stations around the Ms=5.7 earthquake, we have obtained the geomagnetic abnormity associated with this earthquake. Then the geomagnetic abnormity and its relation with seismic activity are discussed in this paper.     

回首邢台地震现场的日日夜夜

记述了1966年3月8日河北邢台地震前中国科学院地球物理研究所地震预报研究工作的进展情况,以及地震发生后地震科技人员在地震现场工作的实践活动,总结了现场工作中提出的一些行之有效的方法,指出了邢台地震现场工作的历史意义。