汾渭地震带时间序列的最大熵谱分析及未来中强震发震概率的最大熵原理估计   总被引：1，自引：0，他引：1  

许俊奇 《地震研究》1992,(1)

本文应用最大熵谱分析的方法和最大熵原理的方法,对汾渭地震带1200年以来发生的Ms≥5.0级地震的时间序列资料进行了分析,结果表明,汾渭地震带历史上Ms≥5.0级的地震存在着250±10年的卓越周期以及今后50年内,发生5.0≦6.0和6.0≦Ms<7.0级地震的概率分别为0.979和0.604,发生Ms>7.0级地震的概率较低,仅为0.199。而5级、6级地震的复发周期分别为12.9年和53.9年等。  相似文献   

中国大陆的特征地震活动及其中—长期预测研究（二）     

闻学泽  罗灼礼 《中国地震》1994,10(3):206-216

在中国大陆，中国震源区过去多次特征地震之间时间间隔的变异系数一般大于０．３５，且在不同的震源区各不相同，以特征地震轮回的ｉ－ｆ－ｊ模式（闻学泽等，１９９４）为基础，将特征地震复发时间Ｔ表示成同一轮回事件ｉ至事件ｆ１的时间差Ｔｉｆ的函数，并发展了估计“当前”轮回平均复发时间的方法，对任一震源区而言，用该方法估计的平均复发时间与过去特征地震时间间隔的表现行为无关，进一步得到Ｔ近似服从于对数正态分布ＬＮ  相似文献   

熵与不确定度区间     

孙海燕 《武汉大学学报(信息科学版)》1994,(1)

测量平差问题中，讨论观测量和参数估值时引入熵及熵意义上不确定度区间的概念，并论证了不确定度区间作为评定精度的指标的可行性，进而提出以不确定度区间作为假设检验的置信区间，避免了选取显著性水平α时的非客观因素的影响。给出了ｔ分布，ｘ２分布、Ｆ分布不确定度区间的计算公式及相应的数表。  相似文献   

Estimation of non-ergodic variograms and their sampling variance by design-based sampling strategies     

D. J. Brus  J. J. de Gruijter 《Mathematical Geology》1994,26(4):437-454

Design-based sampling strategies based on classical sampling theory offer unprecedented potentials for estimation of non-ergodic variograms. Unbiased and uncorrelated estimates of the semivariance at the selected lags and of its sampling variance can be simply obtained. These estimates are robust against deviations from an assumed spatial autocorrelation model. The same holds for the variogram model parameters and their sampling (co)variances. Moreover, an objective measure for lack of fit of the fitted model can simply be derived. The estimators for two basic sampling designs, simple random sampling and stratified simple random sampling of pairs of points, are presented. The first has been tested in real world for estimating the non-ergodic variograms of three soil properties. The parameters of variogram models and their sampling (co)variances were estimated with 72 pairs of points distributed over six lags.  相似文献   

后效严重型强震重复时间讨论   总被引：1，自引：0，他引：1  

秦保燕  刘江峰 《内陆地震》1990,4(2):116-125

本文根据中国七个地区的古地震重复时间统计以及某些大震区的低电阻特性,建立了震源热模型并进行了定量计算。给出了后效严重型的大震(M≥7)的重复时间。  相似文献   

SEISMOTECTONIC BACKGROUND AND RECURRENCE INTERVAL OF GREAT EARTHQUAKES IN 1679 SANHE- PINGGU M = 8 EARTHQUAKE AREA   总被引：2，自引：3，他引：2       下载免费PDF全文

Xiang Hong-fa  Fang Zhong-jing  Xu Jie  Li Ru-cheng Jia San-fa  Hao Shu-jian  Wang Jing-bo  and Zhang Wan-xia 《地震地质》1988,10(1):29

Basined on comprehensive prospecting and investigation, the authors have ascertained that the 1679 San-he-Pinggu M = 8 earthquake occurred in the intersection region of active faults having deep-seated structural background. The NE-trending New Xiadian Fault, which was characterized by dextrall tensile-shear dislocation, was the seismogenic fault of the 1679 M = 8 earthquake. It is suggested that the macroscopic epicenter of the earthquake should be located in Pangezhuang area, where the vertical displacement of seismic faul' was up to 3.16m. According to the average seismic slip rate in this area, and the displacement value of earthequake with a certain magnitude, the recurrence interval of M = 7.5, M=7.0 and M = 8.5 earthquakes in the magistoseismic area of 1679 M = 8 earthquake on Xiadian Fault Zone have been estimated to be 3800,1750, and 800 years (the lower limit), respectively  相似文献   

Slope failures in the Ochil Hills,Scotland, November 1984     

A. Jenkins  P. J. Ashworth  R. I. Ferguson  I. C. Grieve  P. Rowling  T. A. Stott 《地球表面变化过程与地形》1988,13(1):69-76

Intense rainfall in November 1984 caused several slope failures on the steep slopes of the Ochil Hills. Each failure was of soil and till, no more than 2 m thick over bedrock, in a steep bowl. From 30–350 m³ of sediment was removed. Failure seems to have been by shallow sliding triggered by saturation, but each slide became a debris flow, the largest one (Menstrie) filling a house with mud which was at twice the liquid limit two days after the event. The storm which caused the failures had an estimated recurrence interval of 50 years but the frequency of heavy rain is increasing and similar failures occurred nearby the following year.  相似文献   

多滞后区间系数非线性大系统的鲁棒镇定     

李海燕  高存臣  赵有星 《中国海洋大学学报(自然科学版)》2006,36(4):581-584,580

研究一类多时滞非线性大系统的鲁棒镇定问题。利用大系统的分解法将多时滞非线性大系统分解后,首先讨论了无时间滞后情形关联子系统指数镇定的条件，然后考虑多时滞情形，最终给出了多时滞非线性大系统的指数镇定的充分条件；给出了区间长度范围的计算公式和时间滞后的估计公式；通过对比看出。对参数选取加权的方法是有意义的。  相似文献   

2001年永胜6 级地震的地表破裂与程海断裂   总被引：4，自引：0，他引：4  

俞维贤  张建国  周光全  王晋南  曾祥凤 《地震研究》2005,28(2):125-128

综合研究结果表明程海断裂晚更新世晚期以来大地震活动的时间间隔在1500a以上,因此未来一定时间段内,程海断裂还主要以6级左右的中强震为主。  相似文献   

矿井瞬态瑞雷波勘探中若干问题的讨论     

张建军  魏修成 《煤田地质与勘探》2002,30(1):54-57

针对煤矿井下具有地质条件复杂、干扰大的特点,对井下瞬态瑞雷波勘探资料采集和解释若干问题进行了研究。经过大量的现场实验给出了合适的采集参数。通过对记录进行零漂校正、F-K滤波、切除等预处理方法,提高了瞬态瑞雷波勘探的精度和深度。   相似文献