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为探讨玉树地震是否为超剪切破裂事件,利用Yagi的方法重新进行了此次地震震源破裂过程的反演。通过给定不同的破裂速度进行对比,发现当破裂速度为4.7km/s时,理论与实际观测结果拟合残差最小,且反演结果更符合实际。另据P波高频辐射能量包络反演,破裂传播速度在4.7~5.8km/s范围内,而该地区的剪切波速度则为3.0~3.6km/s,从而证明了此次地震超剪切破裂现象的存在。反演结果表明,此次地震在玉树段的NW和SE段形成了19和31km的地表破裂,而震中所在的中段由于隆宝湖拉分盆地的存在,造成了15km的未破裂区。超剪切破裂是造成SE段玉树县城遭受严重破坏的原因之一。 相似文献
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中国居民收入与旅游消费关系的协整分析 总被引:1,自引:0,他引:1
利用协整理论、误差修整模型和Granger因果检验理论,对中国国内旅游消费与居民收入水平之间的关系进行了实证研究,并对城镇和农村居民收入水平与旅游消费之间关系进行了对比分析.结果表明,旅游消费和居民收入之间是长期均衡关系,农村居民收入对旅游消费的促进作用更加明显于城镇居民. 相似文献
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On 16th September 2013, an M5.1 earthquake occurred in Badong County, Hubei Province, which is the biggest one since the first water impounding in 2003 in the head region of the Three Gorges Reservoir area. The crustal velocity information is needed to determine the earthquake location and focal mechanism. By comparison, the 1-D velocity structure model from Zhao was adopted in this study. Double difference location method was applied to determine the precise locations of the M5.1 earthquake sequence. Relocation results show that the dominant distribution of this sequence is along NEE direction. In order to understand its seismogenic structure, focal depth profiles were made. Profile AA' was along the sequence distribution, and the earthquake sequence extended about 12km. Focal depth of mainshock is deeper than that of aftershocks, and earthquake rupture propagated laterally southwestward. The seismic profile BB' and CC' were perpendicular to profile AA', which represent the dip direction. Both profiles show that the focal depth becomes deeper toward southeast, and dip angle is about 50°. It means that the possible seismogenic fault strikes NEE and dips southeast. Focal mechanism could provide more information for judging the seismogenic structures. Many methods could obtain the focal mechanism, such as P-wave first motion method, CAP method, and some other moment tensor methods. In this paper, moment tensor inversion program made by Yagi Y is adopted. 12 regional seismic stations ranging from 100~400km are picked up, and before the inversion, we removed the mean and trend. The seismic waveforms were band pass filtered between 0.05 and 0.2Hz, and then integrated into displacement. Green's functions were calculated using the discrete wavenumber method developed by Kohketsu. The focal mechanism of the M5.1 mainshock manifests that the NEE-striking fault plane probably is the possible seismogenic fault, which is consistent with the analysis of focal depth profiles. The focal mechanisms of the ML≥2.0 aftershocks are retrieved by P-wave first motion method, and the nodal plane I is in accordance with the earthquake sequence distribution and the fault plane of the mainshock. FMSI program was adopted to inverse the stress field in the earthquake area, and the results show that the earthquake sequence is under the control of the regional stress field. The earthquake sequence occurred on the stage of slow water unloading, and ETAS model was introduced to testify the influences of water level fluctuations on earthquakes. The results denote that the reservoir played a triggering role in the earthquake, however, the NEE-striking seismogenic fault is the controlling factor. 相似文献
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通过对周口店岩体地球化学特征和构造环境及其与埃达克岩对比的分析,发现该岩体具有C型埃达克岩的地球化学特征。^143Nd/^144Nd-^87Sr/^86Sr图解发现该岩体的锶、钕同位素投影点均落在EMI型富集地幔区域内,表明其物质来源与EMI型富集地幔有关。而εNd(t)-ISr图解中,其投影点正好落在汉诺坝二辉麻粒岩包体范围内(汉诺坝二辉麻粒岩包体是幔源基性岩浆在晚古生代-中生代底侵到下地壳底部构成的年轻下地壳的一部分)。由此推测认为,周口店岩体是中生代新增生的华北克拉通下地壳的部分熔融的产物。 相似文献
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半参数模型估计的正则核方法 总被引:3,自引:0,他引:3
针对测量数据处理中系统误差对参数估计的影响,提出了半参数估计的正则核方法.这种方法可以在不知道系统误差具体形式的情况下有效地分离系统误差的影响,并且对系统误差进行估计.由于正则项的引入,有效地避免了对非参数部分的过拟合现象,同时对于小样本的观测值也能取得较好效果.最后通过两个算例证明了该方法的有效性. 相似文献
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湖北省巴东县木竹坪滑坡失稳成因分析 总被引:1,自引:0,他引:1
木竹坪滑坡发生于2007年5月10日,总方量约800×104m^3,是水布垭库岸的重大滑坡灾害之一。根据实地调查资料,阐述了滑坡区基本地质条件及滑坡基本地质地貌特征。结合滑坡稳定性计算分析了滑坡的成因机制,认为木竹坪滑坡的发生是内外因共同作用的结果,初步推断认为属于牵引型滑坡。 相似文献
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