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991.
In this paper, we take occurrence process of early strong aftershocks of a main-after shock type′s earthquake sequence as a complex grey system, and introduce predicting method for its stronger aftershocks by grey predicting theory. Through inspection prediction for 1998 Zhangbei MS=6.2 earthquake sequence, it shows that the grey predicting method maybe has active significance for the investigation of quick response prediction problems of stronger aftershocks of an earthquake sequence. 相似文献
992.
A personal computer processing system for simulation of earthquake seismogeny, occurrence and development is given in this paper. It can automatically process the discontinuous events such as earthquake occurrence during computation. The program can be paused when you want to display the computation results. After you analyze these graphical results the simulation process can be continued. 相似文献
993.
WEN-ZHENG YANG 《地震学报(英文版)》1999,12(1):35-45
With the theory of subcritical crack growth, we can deduce the fundamental equation of regional seismicity acceleration model. Applying this model to intraplate earthquake regions, we select three earthquake subplates: North China Subplate, Chuan-Dian Block and Xinjiang Subplate, and divide the three subplates into seven researched regions by the difference of seismicity and tectonic conditions. With the modified equation given by Sornette and Sammis (1995), we analysis the seismicity of each region. To those strong earthquakes already occurred in these region, the model can give close fitting of magnitude and occurrence time, and the result in this article indicates that the seismicity acceleration model can also be used for describing the seismicity of intraplate. In the article, we give the magnitude and occurrence time of possible strong earthquakes in Shanxi, Ordos, Bole-Tuokexun, Ayinke-Wuqia earthquake regions. In the same subplate or block, the earthquake periods for each earthquake region are similar in time interval. The constant αin model can be used to describe the intensity of regional seismicity, and for the Chinese Mainland, α is 0.4 generally. To the seismicity in Taiwan and other regions with complex tectonic conditions, the model does not fit well at present. 相似文献
994.
By means of the hypocenter distribution and focal mechanism of Wuding MS=6.5 earthquake sequence occurred in 1995, the space orientation and activity characteristics of focal fault of Wuding earthquake have been studied from the three-dimensional space-time process. The results indicate that the focal fault of Wuding earthquake is a subsurface, NWW-trending, upright and right-lateral strike slip fault which is consistent with the intensity distribution in the meizoseismal region. Although the large-scale NS-trending Tanglang-Yimen active fault passes through the earthquake region, it is irrelevant to the MS=6.5 Wuding main earthquake. Since the relationship between the strong earthquake and the shallow geological active fault can not be determined, the crustal deep structure should be studied. The method proposed in the paper can be used to distinguish the focal fault in the deep crust. 相似文献
995.
IntroductionOnApril26,1990,anMs=7.0strongewthquakeoccurrednearTanggannofarminnerGonghebasin,QinghaiProvince.Aftertheevent,theSecondCrustalDeformationMonitoringCented,ChinaSeismologicalBureau,immediatelyconductedarelevelingsurveyalongthetwolinesacrosstheearthquakeregioninMayandJuneof1990,thereweretotally27levelingpoilltsreoccupied.Alongwiththelastpre-earthquakelevelingsurveyin1978,abigupliftwiththemaximum345mmatDH20aswellasasmallsubsidencewiththemaximum45.1mmatDH16havebeendetected(Figur… 相似文献
996.
IntroductionI.thasbeenpayingattentiontotheanomalousphenomenonbyseismologiststhattheearthquakeactivityoftenstrengthensinacertainspaceandduringacertaintimearoundthesourceareabeforeastrongearthquake.Mogi(1969)pointedoutthataringdistributiveareaofthestrengthenedearthquakeactivityoftenappearsaroundthesourcearea10to20yearsbeforegreatshock,whichcalledaringphenomenon(or"doughnut").Afterthat,otherscholarsreportedinsuccessionthatringdistributionofearthquakeactivityoccurredbeforeastrongertquakeorevenbefo… 相似文献
997.
IntroductionEarthquakesshowanon-homogeneousdistributionontheEarth'ssurface;inmostregions,therearenoorfeweanhquakestooccur.Mosteanhquakesconcentrateinsomenarrowandlonghugeseismicbelts,forexample,thecircum-Pacificseismicbelt,Alpine-Himalnyanseismicbeltandmid-oceanridgeseismicbelt.Themid-oceanridgeseismicbelttraversesthePacific,Indian,AtlanticandArcticOceanstoformaunifiedandinterconnectedmid-oceanridgeseismicbelt;itisalsoconnectedwiththecircum-Pacific,Alpine-Himalayanseismicbelts.Therefore,t… 相似文献
998.
GUI-PING LIU 《地震学报(英文版)》1999,12(3):277-284
The time and spatial feature of the regional seismicity triggered by the Hyogo-Ken Nanbu, Japan, M=7.2 earthquake on January 17,1995, was studied. The concerned region is about several hundred kilometers in length and breadth surrounding the epicenter (33°~37°N, 133°~138°E). It is divided into 16 subregions. The seismicity of these subregions from January of 1976 to June of 1996 has been analyzed. It is showed that,① there were significant seismicity changes in 10 subregions triggered by the Hyogo-Ken Nanbu, Japan, M=7.2 earthquake on January 17, 1995. These changes passed a Z statistic test exceeding 0.95 confidence level and the greatest epicenter distance of these subregions was 280 km;②seismicity changes were triggered within 1~5 days in three subregions near the main shock while in other subregions the seismicity changes were triggered within several ten days after the main shock;③ the greatest triggered event is 5.4, which is about the same size as the greatest aftershock;④the regional stress change resulted from the main shock may be the triggered mechanism of the regional seismicity. 相似文献
999.
台湾海峡7.3级地震水震波特征研究 总被引:2,自引:2,他引:0
台湾海峡7.3级地震是90年代地震活跃期在我国的一个标志地震。根据全国81口一观测井水震波资料,对其水位振荡、水位阶变、记震距离等方面作了分析。研究结果表明,本次地震显示水位振荡快衰减也快以及水位阶变多、幅度大和不存在最佳记震距离等主要特征,水震小存着丰富的地球信息内涵,这对地震孕育、发生信息的提取有其意义。 相似文献
1000.