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1.
自20世纪70年代至今,中国地震局持续召开年度全国地震趋势会商会,对来年中国大陆地区的地震趋势作出综合判断,按照"东部5级、西部6级以上"的目标划定年度地震危险区.因为年度危险区的形状不规则、预测震级不同以及每年发生地震数量有限,难以对其预测效能进行科学、客观的评价,也不利于通过有真正信息增益危险区来积累预测经验.本研究采用新近发展的"博弈评分"(gambling score)方法评估了年度地震危险区预测结果的显著性.博弈评分是利用"参考模型"计算每个危险区预测成功与否的参考概率作为"奖励"标准,根据实际地震对应情况进行加分或减分.采用泊松模型和古登堡/里克特定律作为参考模型,对1990-2003年期间的年度地震危险区的预测效能进行了评估和分析.结果表明,虽然年度预测效能之间的差异较大,但是年度地震危险区预测结果明显优于非均匀泊松模型.这一方面表明年度地震危险区的圈定含有一定的地震前兆信息,得分高的危险区的判定依据将为提高地震预测准确率提供有益信息并积累有效的经验,另一方面也揭示了年度会商结果在前兆观测资料和地震活动背景空间分布知识之间整合的不足,即年度地震危险区的圈定在技术上仍有提高的余地. 相似文献
2.
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。 相似文献
3.
强震发生前, 震源附近的地震活动往往会呈现出一些空间和时间的异常特征, 分析和提取这些异常特征的方法较多。 本文采用了与常规强震预测方法迥异的地震预测方法地震活动反向追踪法(Reverse Tracing of Precursors, RTP), 对中国大陆近30年来的几个MS≥7.5大震(含2008年5月12日汶川MS8.0地震)进行了探索性的回溯研究。 结果表明, 该方法在中国大陆大震预测方面有一定的适用性, 并利用该方法对中国大陆地区的未来强震活动做了一定的预测。 相似文献
4.
应用“八五”攻关推广的有关震群参数计算的软件 ,对华北地区 (33°～ 43°N,1 1 4°～ 1 2 4°E)自 1 970年以来所发生的 40次震群事件的各项参数 (b,U,H,K,F,ρ等值 )进行了计算 ,旨在依据前兆震群的判定指标 ,寻找前兆震群与中强以上地震 (MS≥ 434)的对应关系。结果表明 ,无论是单项指标或综合指标的报准率均在 65%左右 ,仅有个别达到 75%以上 ,并且有约30 %具有前兆意义的震群属于漏报和虚报。所以 ,如何判定前兆震群和充分利用前兆震群预报地震和监视未来地震活动有待更深入的研究和探讨。 相似文献
5.
Annual Consultation on the Likelihood of Earthquakes in Continental China： Its Scientific and Practical Merits 总被引：4，自引：0，他引：4
Wu Zhongliang 《中国地震研究》2007,21(4):365-371
Since the 1970s, Chinese seismologists have started to conduct the Annual Consultation on the Likelihood of Coming Earthquakes in the Next Year. This approach has unique scientific and practical merits either as an active response to the social needs in the situation that earthquake prediction research meets many difficulties, or as a real forward prediction test persistently conducted for 1/3 century. It is a pity that such an approach has not been well-known by international seismological community, and the scientific merits of such an endeavor is sometimes regrettably underestimated. 相似文献
6.
地震活动性总体参量Rt及其在地震预测中应用的研究 总被引：5，自引：0，他引：5
考虑到地震活动性综合分析在地震预测中的重要作用,提出一种地震活动性总体状态参量Rt。该参量由多项地震活动性预测因子构成,其中包括:地震频次、缺震、地震熵、b值和调制比,该参数描述了某时段内,多种地震活动性参量对正常状态的偏离。当Rt=1时,地震活动状态是稳定的,反之,当Rt<1时,则表明地震活动处于不同程度的不稳定态。文中对华北、东北和西北地区地震以及矿山地震的Rt值在强事件前后随时间的变化进行了研究,初步结果表明:在强震或较大矿震前Rt值明显偏离1。同时,对Rt值的地震预测效能进行了检验评估。 相似文献
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8.
Many uncertainty factors need be dealt with in the prediction of seismic hazard for a 10-year period.Restricted by these uncertainties,the result of prediction is also uncertain to a certain extent,so the probabilistic analysis method of seismic hazard should be adopted.In consideration of the inhomogeneity of the time,location,and magnitude of future earthquakes and the probabilistic combination of the background of long-term seismic hazard(geology,geophysical field,etc.)and the precursors of earthquake occurrence,a model of probabilistic prediction of seismic hazard in a period of 10 years s proposed.Considering the inhomogeneity of data and earthquake precursors for different regions in China,a simplified model is also proposed in order to satisfy the needs of different regions around the country.A trial in North China is used to discuss the application of the model.The method proposed in this paper can be used in the probabilistic prediction of seismic hazard in a period of 10 years.According to the 相似文献
9.
利用活动断裂定量研究资料（滑动速率、古地震等）,结合新疆地区的地震构造环境特征分析,研究了典型潜在震源区大震复发模式,建立了具有区域特征的混合模型,以此评定了新疆地区典型潜在震源区大震的年发生率。混合模型由截断G-R关系模型和特征地震模型构成,计算时先分别计算两个模型的大震分震级档年发生率,然后根据潜在震源区地震地质资料的完备性情况、可靠程度以及大震孕育的区域性特征为两个模型的分震级档结果赋予一定权重,最后求两个模型的加权和。大震复发间隔的计算中利用汶川地震与集集地震的最大垂直位错和平均垂直位错统计关系约束了逆冲型断裂的平均位错量,潜源区的大震年发生率的计算考虑了级联破裂问题。结果表明,本研究所得高震级档大震年发生率比第三代、第四代地震区划图小,文中对这一现象产生的原因进行了初步分析。 相似文献
10.
UNIFIED EARTHQUAKE CATALOG FOR CHINA’S SEAS AND ADJACENT REGIONS AND ITS COMPLETENESS ANALYSIS 
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下载免费PDF全文 China’s seas and adjacent regions are affected by interactions among the Eurasian plate, the western Pacific plate, and the Philippine Sea plate. Both intraplate and plate-edge earthquakes have occurred in these regions and the seismic activities are frequent. The coastal areas of China are economically developed and densely populated. With the development and utilization of marine energy and resources along with the development of national economy, the types and quantity of construction projects in the marine and coastal areas have increased, once an earthquake happens, it will cause huge damage and loss to these areas, therefore, the earthquake-related research for these sea areas cannot be ignored and the need for study on these areas is increasingly urgent. One type of essential basic data for marine seismic research is a complete, unified earthquake catalog, which is an important database for seismotectonics, seismic zoning, earthquake prediction, earthquake prevention, and disaster reduction. Completeness and reliability analysis of an earthquake catalog is one of the fundamental research topics in seismology.
At present, four editions of earthquake catalogs have been officially published in China, as well as the earthquake catalogue compiled in the national fifth-generation earthquake parameter zoning map, these catalogs are based on historical data, seismic survey investigations, and various instrumental observations. However, these catalogs have earlier data deadlines and contain the earthquake records for only the offshore regions of China, which are extensions of coastal land. Distant sea regions, subduction zones, and adjacent sea regions have not been included in these catalogs. Secondly, there were no cross-border areas involved in the compilation of earthquake catalogs in the past. It was not required to use magnitudes measured by other countries’ seismic networks and observation agencies to develop an earthquake catalog with a uniform magnitude scale, moreover, there was no formula suitable for the conversion of magnitude scale in China’s seas areas and adjacent regions. Little research has been conducted to compile and analyze the completeness of a unified earthquake catalog for China’s seas and adjacent regions. Therefore, in this study, we compiled earthquake data from the seismic networks of China and other countries for China’s seas and adjacent regions. The earthquake-monitoring capabilities of different sea areas at different time periods were evaluated, and the temporal and spatial distribution characteristics of epicentral location accuracy for China’s seas and adjacent regions were analyzed. We used the orthogonal regression method to obtain conversion relationships between the surface wave magnitude, body wave magnitude, and moment magnitude for China’s seas and adjacent regions, and established magnitude conversion formulae between the China Seismic Network and the ML magnitude of the Taiwan Seismic Network and the MS magnitude of the Philippine Seismic Network. Finally, we developed an earthquake catalog with uniform magnitude scales for China’s seas and adjacent regions.
On the basis of the frequency-magnitude distribution obtained from the magnitude-cumulative frequency relationship (N-T) and the Gutenberg-Richter(GR)law, we conducted a completeness analysis of the unified earthquake catalog for China’s seas and adjacent regions, Then, we identified the beginning years of each magnitude interval at different focal depth ranges and different seismic zones in the earthquake catalog.
This study marks the first time that a unified earthquake catalog has been compiled for China’s seas and adjacent regions, based on the characteristics of seismicity in the surrounding sea regions, which fills the gap in the compilation of the earthquake catalogue of China’s seas and adjacent areas. The resulting earthquake catalog provides a basis for seismotectonics, seismicity study, and seismic hazard analysis for China’s seas and adjacent regions. The catalog also provides technical support for the preparation of seismic zoning maps as well as for earthquake prevention and disaster reduction in project planning and engineering construction in the sea regions. In addition, by evaluating the earthquake-monitoring capability of the seismic networks in China’s seas and adjacent regions and analyzing the completeness of the compiled unified earthquake catalog, this study provides a scientific reference to improve the earthquake-monitoring capability and optimizing the distribution of the seismic networks in these regions. 相似文献
At present, four editions of earthquake catalogs have been officially published in China, as well as the earthquake catalogue compiled in the national fifth-generation earthquake parameter zoning map, these catalogs are based on historical data, seismic survey investigations, and various instrumental observations. However, these catalogs have earlier data deadlines and contain the earthquake records for only the offshore regions of China, which are extensions of coastal land. Distant sea regions, subduction zones, and adjacent sea regions have not been included in these catalogs. Secondly, there were no cross-border areas involved in the compilation of earthquake catalogs in the past. It was not required to use magnitudes measured by other countries’ seismic networks and observation agencies to develop an earthquake catalog with a uniform magnitude scale, moreover, there was no formula suitable for the conversion of magnitude scale in China’s seas areas and adjacent regions. Little research has been conducted to compile and analyze the completeness of a unified earthquake catalog for China’s seas and adjacent regions. Therefore, in this study, we compiled earthquake data from the seismic networks of China and other countries for China’s seas and adjacent regions. The earthquake-monitoring capabilities of different sea areas at different time periods were evaluated, and the temporal and spatial distribution characteristics of epicentral location accuracy for China’s seas and adjacent regions were analyzed. We used the orthogonal regression method to obtain conversion relationships between the surface wave magnitude, body wave magnitude, and moment magnitude for China’s seas and adjacent regions, and established magnitude conversion formulae between the China Seismic Network and the ML magnitude of the Taiwan Seismic Network and the MS magnitude of the Philippine Seismic Network. Finally, we developed an earthquake catalog with uniform magnitude scales for China’s seas and adjacent regions.
On the basis of the frequency-magnitude distribution obtained from the magnitude-cumulative frequency relationship (N-T) and the Gutenberg-Richter(GR)law, we conducted a completeness analysis of the unified earthquake catalog for China’s seas and adjacent regions, Then, we identified the beginning years of each magnitude interval at different focal depth ranges and different seismic zones in the earthquake catalog.
This study marks the first time that a unified earthquake catalog has been compiled for China’s seas and adjacent regions, based on the characteristics of seismicity in the surrounding sea regions, which fills the gap in the compilation of the earthquake catalogue of China’s seas and adjacent areas. The resulting earthquake catalog provides a basis for seismotectonics, seismicity study, and seismic hazard analysis for China’s seas and adjacent regions. The catalog also provides technical support for the preparation of seismic zoning maps as well as for earthquake prevention and disaster reduction in project planning and engineering construction in the sea regions. In addition, by evaluating the earthquake-monitoring capability of the seismic networks in China’s seas and adjacent regions and analyzing the completeness of the compiled unified earthquake catalog, this study provides a scientific reference to improve the earthquake-monitoring capability and optimizing the distribution of the seismic networks in these regions. 相似文献
11.
随着世界上多个国家和地区的地震预警系统投入运行,误报和漏报等问题逐渐突显,特别是将标定以及强干扰波形误识别为大震事件,快速、精确地区分地震与其他波形是一个难题。针对于此,该研究提出了基于卷积神经网络地震波形智能识别方法。首先收集并处理了2012—2017年中国境内福建以及周边邻省共683个地震和478个爆破事件,并对这些样本筛选、截取和基线校正等预处理,共得到了27 500条三通道波形。在此基础上,构建了3 s波形输入的卷积神经网络模型(SW-CNN)。结果表明：模型对地震、噪声、爆破和异常波形的识别率分别为97.9、99、99.2和99.3%。相比于人工手动分类识别,该模型更省时和更稳定,为地震预警目前所面临的问题提供了一个新的解决方法。 相似文献
12.
IntroductionI.thasbeenpayingattentiontotheanomalousphenomenonbyseismologiststhattheearthquakeactivityoftenstrengthensinacertainspaceandduringacertaintimearoundthesourceareabeforeastrongearthquake.Mogi(1969)pointedoutthataringdistributiveareaofthestrengthenedearthquakeactivityoftenappearsaroundthesourcearea10to20yearsbeforegreatshock,whichcalledaringphenomenon(or"doughnut").Afterthat,otherscholarsreportedinsuccessionthatringdistributionofearthquakeactivityoccurredbeforeastrongertquakeorevenbefo… 相似文献
13.
年度地震危险区预测问题的几点初步思考 总被引：2，自引：0，他引：2
本文通过我国年度地震危险区预测对应情况的简要分析，认为年度地震危险区判定的时效定位和异常依据的选取等存在值得注意的问题。提出年尺度中期或中短期地震危险区预测应根据不同地区震情跟踪研究进行科学的动态判定。 相似文献
14.
华北地区的背景地震活动及区域未来强震危险性 总被引：3，自引：0，他引：3
华北地区的历史强震活动非常频繁。 然而, 自1998年张北MS6.2地震以来, 该地区已经经历了10多年的地震平静期, 中强震平静现象比较突出。 本文利用1970年至2009年的小震资料, 对华北地区的背景地震活动进行分析, 给出了地震活动性参数b值、 最大震级以及强震复发间隔和强震年平均发生概率的空间分布。 b值空间分布表明, 山西构造带的运城地区, 郯庐断裂带的宿迁地区以及太行山块体内部的石家庄地区的b值较低。 地震活动性参数的综合空间图像表明华北地区的地震活动主要受区域深部动力因素所控制。 相似文献
15.
为了及时、准确、可靠地发出地震预警信息,本文提出了一种基于贝叶斯理论的地震P波双参数预警方法。选取中国地震台网中心记录的四川地区的355条地震数据,统计P波触发后前3 s的P波平均周期τc和位移幅值Pd,结合贝叶斯理论建立震级和峰值加速度的预测模型,并以震级M4.5和峰值加速度为120 cm/s2为预警阈值,建立了地震危害性判别模型。与传统拟合方法进行对比仿真分析,并以汶川MS8.0地震为震例,进行地震危害性判别实验与分析。实验结果表明:本文提出的基于贝叶斯理论的地震 P 波双参数预警方法比传统拟合方法地震漏报率低 15.15%,可以快速、准确地估计震级与峰值加速度,并有效地评估地震的危害性,能够为地震监测预警提供数据支持和决策依据。 相似文献
16.
在对新疆1973年以来年度地震预测情况进行综合研究基础上,重点分析了乌恰-喀什周围地区年度预测的阶段性特点,并对这一地区1900年以来M≥6地震和1972-2008年M≥5.5地震活动特征进行了的研究.认为对该区域地震活动规律性特点认识不足,没有遵循本地区地震活动的基本规律对地震趋势进行客观判断,是造成地震危险区预测效果较差的主要原因.依据地震活跃与间歇的特点认为2008年底开始乌恰-喀什周围地区将进入一个新的活跃时段,这一地区可能仍将继续被划定为年度强地震危险区. 相似文献
17.
Jiang Zaisen Zhao Zhencai Wang Haitao Wang Jiying and Wang ShuangxuThe Second Crustal Deformation Monitoring Center SSB Xi'an China Seismological Bureau of Xinjiang Uygur Autonomous Region Urumqi China 《中国地震研究》1998,(4)
In this paper, the process of medium- and short-term prediction (submitted in special cards) of the Artux earthquake (MS=6.9) and the Usurian earthquake (MS=5.8) in Xinjiang area, is introduced. The imminent seismic risk regions are judged based on long- and medium-term seismic risk regions and annual seismic risk regions determined by national seismologic analysis, combined with large seismic situation analysis. We trace and analyze the seismic situation in large areas, and judge principal risk regions or belts of seismic activity in a year, by integrating the large area's seismicity with geodetic deformation evolutional characteristics. As much as possible using information, we study synthetically observational information for long-medium- and short-term (time domain) and large-medium -small dimensions (space domain), and approach the forecast region of forthcoming earthquakes from the large to small magnitude. A better effect has been obtained. Some questions about earthquake prediction are discussed. 相似文献
18.
图像信息方法是一种基于统计物理学的地震预测方法. 该方法通过严格的统计检验给出地震活动状态显著偏离平均状态的地区(即显著平静或显著活跃的地区), 称为“地震热点”. 以往研究结果表明该方法是一个预测效能较高的中长期地震预测方法. 本文利用中国地震台网中心提供的1970年以来的地震目录, 在剔除余震、 选取完备震级的基础上, 基于前期研究工作结果中预测效能较高的计算参数, 即网格尺度为2°×2°、 预测时间窗为9年, 分析2008年汶川MS8.0地震后到2013年芦山MS7.0地震前川滇地区的图像信息演化过程. 结果表明, 2009—2010年间芦山MS7.0地震震中附近的鲜水河断裂带、 龙门山断裂带和安宁河断裂带交汇区(29°—31°N, 101°—105°E)存在明显的地震热点, 2011—2012年该地震热点缩小至(29°—31°N, 101°—103°E)范围, 2012年以后消失, 继而于2013年发生芦山MS7.0地震. 本文还对比研究了网格尺度为1°×1°时的图像信息演化过程, 结果显示2009—2010年芦山地震附近的新津—成都—德阳断裂南部、 龙泉山西缘断裂南段、 马边—盐津断裂带、 峨边断裂带、 天全—萦经断裂带(29°—30°N, 103°—104°E)也出现过地震热点, 2011年以后该热点消失, 2013年发生芦山MS7.0地震. 本文讨论了计算参数对预测结果的影响, 并根据目前存在的地震热点分析了川滇及附近地区今后强震发生的可能地点. 相似文献
19.
利用川滇南部GPS站点速度资料,采用Kriging插值和有限单元中形函数(拉格朗日差值函数)求导原则,计算了川滇南部主应变速率.在此基础上,引入Kostrov地震矩率计算方法,由主应变速率求得了研究区的地震矩率,进而借助于Ward地震平均复发间隔公式计算了研究区地震(MS≥6.5)平均复发间隔.计算结果表明,川滇南部不同震级档地震复发间隔空间分布总体上与区内主要活动断裂展布基本吻合;地震复发间隔低值区主要分布在地震活动水平和滑动速率较高的安宁河—则木河—小江断裂带、丽江—小金河断裂西南段、红河断裂西北段.所得的结果与利用历史地震资料获得的结果基本一致.该方法对于历史地震资料缺乏或不完整地区和活动断层定量研究程度较低的地区有着潜在的应用价值. 相似文献
20.
中国大陆及邻区地震活动周期及显著性检验 总被引：1，自引：0，他引：1
本文针对中国大陆及邻区和中国大陆地区的不同起始震级的地震资料的不同时间段、 不同数据预处理的地震应变能(贝尼奥夫应变)进行小波分析, 研究不同区域的地震活动周期谱及其显著性水平(即置信度), 结果表明: ① 在中国大陆及邻区的地震活动周期谱中, 23年左右周期的置信度超过95%; 45年和90年左右周期的置信度为90%左右。 ② 中国大陆地区存在明显的25年左右周期, 置信度超过95%, 而其它周期并不明显。 ③ 无论是中国大陆地区还是中国大陆及邻区, 同一个周期的置信度随计算资料的起始震级减小而降低。 特别是中国大陆地区和大陆及邻区都存在置信度超过95%的23～25年周期对于地震的活跃与平静预测具有现实意义。 而中国大陆及邻区地震活动的数十年或百年尺度的周期在地震趋势估计中是不应该被忽视的因素。 相似文献