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A. Ya. Sidorin 《Seismic Instruments》2010,46(4):351-355
A search for technogenic effects in the time series of earthquakes in Greece is carried out. The ine- quality of intra-week distributions of earthquakes including the events of M ≥ 3.7 is shown. Sharp changes in the pattern of Rayleigh-Schuster’s hodograph for the diurnal periodicity of earthquakes were revealed. They are located in the time vicinity of the moments of the equinox. The result supports the idea of the natural gen- esis of the diurnal periodicity of earthquakes and the important role of the Sun. 相似文献
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A. Ya. Sidorin 《Seismic Instruments》2010,46(4):377-382
A search for technogenic effects in the time series of earthquakes in Greece is carried out. The ine- quality of intra-week
distributions of earthquakes including the events of M ≥ 3.7 is shown. Sharp changes in the pattern of Rayleigh-Schuster’s
hodograph for the diurnal periodicity of earthquakes were revealed. They are located in the time vicinity of the moments of
the equinox. The result supports the idea of the natural gen- esis of the diurnal periodicity of earthquakes and the important
role of the Sun. 相似文献
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A. I. Lutikov E. A. Rogozhin G. Yu. Dontsova M. S. Kuchai 《Izvestiya Physics of the Solid Earth》2018,54(2):233-251
Based on the seismological, geodynamic, and seismotectonic data on the strongest series of earthquakes in 2009–2017 in Central Italy, which were collected by many researchers, mostly Italian, the tectonic position of these events is determined and the seismic history of the region over more than 2000 years of observations of seismic manifestations in Italy is traced in the context of the strong events of the beginning of the 21st century. The aftershock processes of these earthquakes are investigated and, as a result, the possibility of a series of strong aftershocks of the earthquake of October 30, 2016 (MW = 6.6) is predicted in advance of the actual occurrence of these events on January 18, 2017. 相似文献
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青藏高原是我国现代构造活动和地震活动最强烈的地区,自有地震记录以来,在高原内记录到多达18次8级以上巨大地震和100余次7~7.9级地震,它们均发生在喜马拉雅板块边界构造带和板内断块区及其次级断块的边界活动构造带上.自1900年有地震仪器记录以来,青藏高原曾经历了3次地震活动丛集高潮,即1920-1937年,1947-1976年和1995-现在.在每次地震活动丛集期都形成以8级地震为核心的7级以上地震活动系列,它们分别是20世纪20-30年代的海原-古浪地震系列、50-70年代察隅-当雄地震系列和20世纪末期以来昆仑-汶川地震系列.每一个地震系列都有自己的主体活动区,最新的昆仑-汶川地震系列的主体活动区为巴颜喀喇断块.青藏高原地震活动高潮与全球Mw≥8.0巨大地震活动高潮紧密相关,昆仑-汶川地震系列与自2001年至今的全球最新地震活动高潮相对应,它们反映了两者的动力学联系.经过详细对比研究认为,它们至今均仍在延续之中,全球板块边界构造带8~9级地震和板内大陆断块区的7~8级地震都仍在连续发生.研究了全球和区域地震活动的相关关系及青藏高原地震活动的时空分布特征,指出了该区当前地震活动的总体形势,评价了其近期地震危险性,提出了加强地震监测的建议. 相似文献
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Gennadiy V. Ryabinin Valeriy A. Gavrilov Yuriy S. Polyakov Serge F. Timashev 《Acta Geophysica》2012,60(3):874-893
We propose a new type of earthquake precursor based on the analysis of correlation dynamics between geophysical signals of
different nature. The precursor is found using a two-parameter cross-correlation function introduced within the framework
of flicker-noise spectroscopy, a general statistical physics approach to the analysis of time series. We consider an example
of cross-correlation analysis for water salinity time series, an integral characteristic of the chemical composition of groundwater,
and geoacoustic emissions recorded at the G-1 borehole on the Kamchatka peninsula in the time frame from 2001 to 2003, which
is characterized by a sequence of three groups of significant seismic events. We found that cross-correlation precursors took
place 27, 31, and 35 days ahead of the strongest earthquakes for each group of seismic events, respectively. At the same time,
precursory anomalies in the signals themselves were observed only in the geoacoustic emissions for one group of earthquakes. 相似文献
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We examined forecasting quiescence and activation models to obtain the conditional probability that a large earthquake will occur in a specific time period on different scales in Taiwan. The basic idea of the quiescence and activation models is to use earthquakes that have magnitudes larger than the completeness magnitude to compute the expected properties of large earthquakes. We calculated the probability time series for the whole Taiwan region and for three subareas of Taiwan—the western, eastern, and northeastern Taiwan regions—using 40 years of data from the Central Weather Bureau catalog. In the probability time series for the eastern and northeastern Taiwan regions, a high probability value is usually yielded in cluster events such as events with foreshocks and events that all occur in a short time period. In addition to the time series, we produced probability maps by calculating the conditional probability for every grid point at the time just before a large earthquake. The probability maps show that high probability values are yielded around the epicenter before a large earthquake. The receiver operating characteristic (ROC) curves of the probability maps demonstrate that the probability maps are not random forecasts, but also suggest that lowering the magnitude of a forecasted large earthquake may not improve the forecast method itself. From both the probability time series and probability maps, it can be observed that the probability obtained from the quiescence model increases before a large earthquake and the probability obtained from the activation model increases as the large earthquakes occur. The results lead us to conclude that the quiescence model has better forecast potential than the activation model. 相似文献
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地震活动图像特征与强震危险区经验性预测依据的初步研究 总被引：1，自引：0，他引：1
在研究近期（10年）强震危险性判定和总结四川地区1972--2002年强震预测经验的基础上，清理了中国大陆1920--2002年47次浅源大震事件前地震活动图像特征（M≥4．7），提炼出10个方面12项经验性预测依据：主体活动区、多发时段、关联序列、大陆及地区地震异常图像、地区（带）-地段（震源区）地震增强图像（含信号震、诱发地震、地震条带）、相关地震、窗口地震、复发间隔、大陆及地区缺震、地段缺震与地段强震一缺震转折等。它们在47次震例中的综合出现率≥0．58（即依据比7／12以上）占42例；≥0．66（即8／12以上）占34例。因此，强震（M≥4．7）活动图像经验性预测依据可以作为预测有较大可能发生大地震危险区的依据之一。 相似文献
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It is expected that episodic tremors and slips (ETS) as a type of slow earthquakes with periodic property will be detected using harmonic estimation techniques. The principal goal of this paper is the detection of these kinds of earthquakes using least squares harmonic estimation (LSHE). To accomplish this, the raw time series of 38 permanent GPS stations of the Pacific Northwest Geodetic Array have been analyzed. Previously, some independent techniques could confirm the occurrences of the aforementioned quakes at these stations. However, the current research intends to evaluate the spectrum of each of the de-trended time series using the LS-HE method. In each station, the period of the detected harmonic with the maximum power spectrum is equivalent to the average period previously reported for these events. According to the obtained results, the recurrence interval of these events ranges from 9 months to 3 years. In sum, the study confirms this method being efficient for investigating the occurrences of ETSs when the length of the GPS time series is sufficiently large. 相似文献
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长白山天池火山地震类型及火山活动性的初步研究 总被引：3，自引：0，他引：3
2002年以来，长白山天池火山区出现了地震活动增强、地形变加剧和多种地球化学异常等现象，火山口附近发生的多次有感地震在社会上产生了较大影响。本文利用2002年以来的流动地震观测资料，采用频谱分析、时频分析和多台站资料对比的方法，对火山区地震事件的类型进行了分析；对火山活动的危险性进行了初步研究。结果表明，目前天池火山区出现的大量地震活动仍然属于火山构造地震，少量台站地震记录中表现出的低频特征主要是由于局部介质影响造成的，排除了长周期地震引起的可能。尽管长白山天池火山地震活动明最增强，震群活动较为频繁，但仍属于岩浆活动的早期阶段，短期内发生火山喷发的危险性较小。 相似文献
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研究了14世纪以来中国的5大地震系列,5大地震系列在“山字型”构造格局上分布,并且依次以东→中→西→东→西顺序发生大地震系列。在1303—2005年约702年时间内发生的5大地震系列,为第一轮回。在此后者,则应为第二轮回。 相似文献
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A. M. Posadas F. Vidal J. Morales J. A. Pe a J. Iba ez F. Luzon 《Physics of the Earth and Planetary Interiors》1993,80(3-4):159-168
The three point method (TPM) has been successfully applied to several seismic series and has provided information about the spatial characteristics (azimuth and dip) of the fault planes activated in the rupture process. A new development of the TPM to determine temporal characteristics, is presented, to obtain the evolution of the fracturing process of an active fault system. For the analysis of the 158 microearthquakes and earthquakes that took place in the seismic series of Antequera in June 1989, the choice of a threshold magnitude (mu = 2.5) has permitted the events related to the most relevant fractures to be distinguished. Secondly, only the events between two concentric spheres (here named Spatial Crown) with respect to a given earthquake, have been used in order to avoid taking into account earthquakes that are too close to each other, together with the very distant events that have little relation to the event analysed. The Spatial Crown has permitted some clear results in the Antequera series, where we have found that the fracturing process began fundamentally with N 80° E planes and evolved to N 65° W planes. Finally, an error analysis enables an estimation of the uncertainty in the results to be obtained from the errors in the data. 相似文献
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自2008年汶川MS8.0地震发生以来,四川盆地内部及盆地边缘发生了一系列MS≥4.5地震,部分地震发生之后,四川及邻区又发生了MS≥6.0强震。2019年6月17日四川长宁MS6.0地震后,对四川盆地内部及盆地边缘MS≥4.5地震的预测意义进行了研究和疏理。通过给定不同的预测规则,对上述MS≥4.5地震的预测效能进行了统计检验,结果表明:仅四川盆地内部,以三台、梓潼等区域为代表的历史少震与弱震区MS≥4.5地震对四川及邻区未来半年内发生MS≥6.5地震具有显著的预测意义。 相似文献
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利用地基GPS观测数据研究与地震有关的电离层异常 总被引：3，自引：0，他引：3
利用中国大陆GPS连续站观测数据, 根据电离层单层模型, 计算得到中国大陆上空电离层电子总含量TEC(Total Electron Content)值的时间序列。 选取2001—2008年发生在中国大陆地区的11个MS≥6.0地震, 分析了这11个地震前后TEC值时间序列的变化特征。 分析结果显示, 地震活动期间距离震中700 km以外的GPS连续观测站上空TEC值的异常现象不明显, TEC值变化基本在0.5 TECU之内。 11个震例中有6个震例TEC值出现了负异常现象, 主要表现在震前1～5 d, 并且观测站距离震中越近, TEC值变化越明显, 少数震例在地震发生期间TEC值明显增加。 研究认为, 利用GPS连续观测数据研究与地震有关的电离层前兆是可能的。 相似文献
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1977——1984年,华北南部连续发生了溧阳、邢台、菏泽、南黄海四次六级左右地震。分析表明: 1)这些地震均位于华北块体南边界构造网络的节点上; 2)唐山大震的发生引起块体南边界断裂带的活动加剧,并伴随应力重新分布,导致上述地段应力加强和周围广大区域应力下降,形成了有利于这些地震孕育的应力场背景; 3)当网络上某一个薄弱点发生破裂后,会引起应力再分布,从而影响着下一次地震的发生,这种快速的应力调整过程,对于中强地震的能量积累和它们的成组发生起了重要作用。研究地震现象在时空上的相互作用过程,对于地震的中短期预报具有重要意义。 相似文献
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A Preliminary Study of the Types of Volcanic Earthquakes and Volcanic Activity at the Changbaishan Tianchi Volcano 总被引：1，自引：0，他引：1
Ming Yuehong 《中国地震研究》2006,20(3):286-294
INTRODUCTIONThe Changbaishan volcano is located in Jilin Province , along the border of China and NorthKorea .It isthelargest nature reservein China .Changbaishan belongstothe northeastern Asian activebelt in the eastern margin of the Euro-Asia plate . The Changbaishan volcano is a gigantic ,polygenetic ,central volcano,and has been active since Holocene .The early eruption started in thePliocene andformedthe basaltic shield. Duringthe middle and late Pleistocene ,the volcanic cone … 相似文献
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We develop stochastic approaches to determine the potential for tsunami generation from earthquakes by combining two interrelated
time series, one for the earthquake events, and another for the tsunami events. Conditional probabilities for the occurrence
of tsunamis as a function of time are calculated by assuming that the inter-arrival times of the past events are lognormally
distributed and by taking into account the time of occurrence of the last event in the time series. An alternative approach
is based on the total probabilitiy theorem. Then, the probability for the tsunami occurrence equals the product of the ratio,
r (= tsunami generating earthquakes/total number of earthquakes) by the conditional probability for the occurrence of the next
earthquake in the zone. The probabilities obtained by the total probability theorem are bounded upwards by the ratio r and, therefore, they are not comparable with the conditional probabilities. The two methods were successfully tested in three
characteristic seismic zones of the Pacific Ocean: South America, Kuril-Kamchatka and Japan. For time intervals of about 20
years and over the probabilities exceed 0.50 in the three zones. It has been found that the results depend on the approach
applied. In fact, the conditional probabilities of tsunami occurrence in Japan are slightly higher than in the South America
region and in Kuril-Kamchatka they are clearly lower than in South America. Probabilities calculated by the total probability
theorem are systematically higher in South America than in Japan while in Kuril-Kamchatka they are significantly lower than
in Japan. The stochastic techniques tested in this paper are promising for the tsunami potential assessment in other tsunamigenic
regions of the world. 相似文献