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Statistical learning theory is for small-sample statistics. And support vector machine is a new machine learning method based on the statistical learning theory. The support vector machine not only has solved certain problems in many learning methods, such as small sample, over fitting, high dimension and local minimum, but also has a higher generalization (forecasting) ability than that of artificial neural networks. The strong earthquakes in Chinese mainland are related to a certain extent to the intensive seismicity along the main plate boundaries in the world, however, the relation is nonlinear. In the paper, we have studied this unclear relation by the support vector machine method for the purpose of forecasting strong earthquakes in Chinese mainland. 相似文献
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Introduction Through studying ″foreshock″ and sequence features of strong earthquakes with focal mechanism of strike-slip or thrust occurred in the shallow subduction zone or in the continental thrust belt respectively, Reasenberg (1999) suggested that precursory representation and the se- quence features are related tightly to the rupture mechanism of the mainshock. This implies that the rupture pattern of the mainshock is probably one of the important factors affecting the features of afte… 相似文献
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Statistical features of aftershock distribution size for moderate and large earthquakes in Chinese mainland 总被引:1,自引:0,他引:1
Based on data of earthquake sequences with MS≥5.0 in Chinese mainland from 1970 to 2004,for different se-quence types and different rupture modes of the main shock,the relationship between aftershock distribution size Rand the magnitude of the main shock M0 has been studied statistically.Considering the rupture mode of the mainshock,we give the quantitative statistical relationships between R and M0 under 95%confidence level for differentsequence types.Qualitatively,lgR,the logarithm of the aftershock distribution size,is positively correlative to theM0,but the data distribution is dispersed.Viewing from different sequence types,the correlation between R and M0is very weak for isolated earthquake type(IET)sequence,R distributes in the range from 5 to 60 km;For main-shock-aftershock type(MAT),lgR is positively correlative to M0;For multiple main shock type(MMT),the core-lation between lgR and M0 is not very obvious when M0≤6.2 and R distributes in the range from 5 to 70 km,whileit shows a linear correlation when M0≥6.3.The statistical results also show that the occupational ratios of differentsequence types for strike-slip and oblique slip are almost the same.But for dip-slip(mostly are thrust mechanisms),the ratio of MAT is higher than that of IET and MMT.Comparing with previous results,it indicates that,when M0is large enough,R is mainly determined by M0 and there is almost no relationship with the rupture mode of themain shock. 相似文献
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General characteristics of the recent horizontal crustal movement in Chinese mainland 总被引:5,自引:0,他引:5
1 Introduction of GPS observation dataThe Crustal Movement Observation Network of China (CMONOC) is a major scientific project in China organized by China Seismological Bureau and paticipated by the Bureau of Surveying and Mapping of the General Staff, the Chinese Academy of Sciences and the National Bureau of Surveying and Mapping. Based on the observation data of 25 fiducial stations and 56 basic stations in CMONOC (Figure 1 and Table 1), collected from August 26 to September… 相似文献
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IntroductionThe study on earthquake nucleation is widely concerned by seismologists in the world. The experimental and theoretical studies indicate that earthquakes should be preceded by quasi-static slip within a nucleation zone (Ohnaka, 1992; Dodge, Beroza, 1995; Dodge, et al, 1996; Ohnaka, Kuwahara, 1990; Yamashita, Ohnaka, 1991). The earthquake nucleation process means a transition from quasi-static to quasi-dynamic rupture process, and it itself is a short-term precursor. Immediate fo… 相似文献
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IntroductionAnisotropy is a universal phenomenon in the upper mantle. The mechanisms, which cause elastic anisotropy of in-situ rocks, include lattice preferred orientation of the minerals composing the rocks and preferred orientation of magma chambers. Lattice preferred orientation (LPO) of olivine is widely believed to be the dominant cause of the upper mantle anisotropy. The observational results of the upper mantle anisotropy can be explained by tectonic process relating to plate motion.… 相似文献
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IdentifyingtheactiveandinactiveperiodofearthquakesinChinesemainlandisofgreatimportanceforguid-ingmid-shortterm,especiallyshortterm,earthquakeforecast.Thisisanindispensablestepforstudyingearth-quakepredictioninourcountry.Nowanintegratedsetofconceptsandmethodsforgeneraltrendpredictionofearthquakeactivityhasbeendeveloped.BasedontheChineseearthquakedatasincethebeginningofthe20thcentury,somestatisticalmethodshavebeendevelopedtoanalyzeoccurrencefrequencyandenergyreleaseofearthquakes,distinguishacti… 相似文献
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EarthquakemigrationinEastAsiamainland(Ⅰ)──ThemigrationofhugeearthquakesandvolcanicactivityfromWestPacificTrenchtotheChinese m... 相似文献
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StudyoftheanomalyofseismicfractalspectrumbeforestrongearthquakesLINGRENZHU1)(朱令人)SHIYONGZHOU1)(周仕勇)MALINGYANG1)(杨马陵)HAIT... 相似文献
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Introduction In the last 20 years, with observation technique development in space monitoring to Earth, a large progress has been made in monitoring crustal movement. This makes it possible for us to study crustal movement and the present geodynamic. Continuous GPS observation conducted in Chinese mainland and its neighboring region provides us for studying the present strain field of crustal micro-behavior tectonic. Crustal micro-behavior tectonic means that we can study the dif-ference bet… 相似文献
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Recurrence behaviors of segment-rupturing earthquakes on active faults of the Chinese mainland 总被引:3,自引:0,他引:3
闻学泽 《地震学报(英文版)》1999,12(4):457-465
IntroductionStrongorlargeearthquakesoccurredalongaspecificsegmentofanactivefaultarecalledsegment-rupturingearthquakes.Suchearthquakesoccurrepeatedlyatpreviouslocations.Thecurrentrecurrencemodelsforearthquakesrepeatedatpreviouslocationswereproposedonlimiteddatafromcharacteristicearthquakesonplateboundaries,mainlyincludingthetime-predictableandslippredictablemodels(Shimazaki,Nakata,1980),thequasi-periodicmodel(Bakun,McEvilly,1984;Savage,Cockerham,1986),andthetime-andmagnitude-predictablemodel… 相似文献
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《地震研究进展(英文)》2023,3(1):100177
The long-term earthquake prediction from 2021 to 2030 is carried out by researching the active tectonic block boundary zones in the Chinese mainland. Based on the strong earthquake recurrence model, the cumulative probability of each target fault in the next 10 years is given by the recurrence period and elapsed time of each fault, which are adopted from relevant studies such as seismological geology, geodesy, and historical earthquake records. Based on the long-term predictions of large earthquakes throughout the world, this paper proposes a comprehensive judgment scheme based on the fault segments with the seismic gap, motion strongly locked, sparse small-moderate earthquakes, and apparent Coulomb stress increase. This paper presents a comprehensive analysis of the relative risk for strong earthquakes that may occur in the coming 10 years on the major faults in the active tectonic block boundary zones in the Chinese mainland. The present loading rate of each fault is first constrained by geodetic observations; the cumulative displacement of each fault is then estimated by the elapsed time since the most recent strong earthquake. 相似文献
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Distribution of empirical recurrence intervals for segment-rupturing earthquakes on active faults of the Chinese mainland 总被引:2,自引:0,他引:2
闻学泽 《地震学报(英文版)》1999,12(6):667-675
IntroductionInassessingtheprobabilitiesoftime-dependentandlong-termseismichazardsforsegmentsofactivefaults,itisnecessarytohavetheprobabilitydensity,f(O,fordescribingtherecurrenceintervaldistributionforsegment-rupturingearthquakes.Fromf(nandthefollowingequation,theconditionalprobability,pc,whichincreaseswiththetime,Te,elapsedsincethelatestearthquake,isabletobecalculated(Nishenko,Buland,1987,WorkingGrouponCaliforniaEarthquakeProbabilities,1995;Wen,1995,1998)fwhereATisthetimeintervalforthefor… 相似文献
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地震预测面临着地球内部的"不可入性"和大地震"非频发性"的问题,是极具挑战性且尚待解决的世界性科学难题之一(陈运泰,2009) .地震活动是断裂活动的直接体现,精定位的震源深度客观反映了断裂深部发生地震滑动变形的起始位置.断裂深部发生的慢滑动和重复地震等对揭示断裂深部行为具有重要的指示意义(Harris,2017).在... 相似文献
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中国大陆强震时空关联特征及应用 总被引:4,自引:0,他引:4
根据我国大陆强震成组活动的特征,以强震诱发和成组孕育理论为基础,对我国近30年以来的强震进行At值扫描,并对其作出了系统分析和R值评分,据此对我国地震大形势进行了一定程度的预测。 相似文献
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Introduction It is well known that China locates in the southeastern part of Eurasian Plate, which subjects to the action of westward subducting of Pacific Plate and Philippine Sea Plate, and northward col- lision of Indian Plate. So China is a country with strong seismicity. There are two kinds of earth-quake activities in China. In the Chinese mainland most of the earthquakes belong to the intraplate ones, and in Taiwan of China belong to interplate ones. According to the statistics 9… 相似文献
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中国陆区孕震环境具有“垂向分层,横向分块”的特征,活动地块边界带对中国陆区的强震具有控制作用,针对活动地块边界带主要断层开展10年尺度强震危险性定量研究对抗震设防工作有重要意义.本文综合不同区域断层离逝率样本建立了中国陆区通用强震复发模型,在此基础上,对各断层段强震概率进行预测.由于中国陆区幅员辽阔,不同断层的研究程度有较大差距,部分断层由于缺乏计算离逝率的资料而无法获得强震概率.因此本文使用不同方法对相关资料进行了补充.针对缺乏强震复发周期记录的断层段,通过统计断层运动速率与强震复发周期的经验关系,使用地震地质资料或大地测量资料给出的断层运动速率计算强震复发周期;针对缺乏强震离逝时间记录的断层段,根据地震目录完整时间给出强震离逝时间的分布.在此基础上,获得了中国陆区活动地块边界带主要断层的391个断层段未来10年的强震累积概率和条件概率.由于相对预测时长对条件概率的影响较大,而中国陆区不同断层段的强震复发周期有较大差别,本文主要依据累积概率分析强震危险性.结果表明,未来10年强震危险性较高的断层段主要集中于川滇菱形地块东边界、青藏高原东北缘、鄂尔多斯地块东边界与西北边界、天山地区和喜马拉雅弧等区域.
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