Inversion of roughness parameters of self-affine surfaces from backscattered waves     

Stéphanie Gautier  Dominique Gibert 《Geophysical Journal International》2005,160(3):797-803

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Clustering of Earthquake Events in the Himalaya - Its Relevance to Regional Tectonic Set-up   总被引：1，自引：0，他引：1  

Basab Mukhopadhyay  Sabyasachi Dasgupta  Sujit Dasgupta 《Gondwana Research》2004,7(4):1242-1247

The earthquake events of Himalaya of magnitude ≥5.0 from the time window 1905–2000 are statistically analysed. The inter-event time between earthquakes shows Hurst phenomena of temporal clustering which are spatially located in five distinct domains along the Himalayan fold-thrust belt. Out of these, two domains, one around Uttaranchal-Nepal border and the other around Nepal-Sikkim border reveal maximum number of temporal clusters and thus considered as seismically most potential zones of the Himalaya. Both these zones are located at the interface of the orthogonally disposed major tectonic discontinuities of the Peninsular Shield and Himalayan fold-thrust belt. Such zones are geologically most favourable locales for strain accumulation during later-tectonic movement. Statistical analysis points towards a probability of recurrence of seismic events in near future in these two zones. However, validity of such statistical results can be ascertained by detailed geological and geophysical modelling of the terrain.  相似文献   

Rescaled range ( R/S ) analysis on seismic activity parameters     

Li Juan  Chen Yong 《地震学报(英文版)》2001,14(2):148-155

The rescaled range (R/S) analysis, proposed by Hurst, is a new statistical method. Being different from traditional statistical method, R/S analysis can provide the information of maximum fluctuation (range) of statistical parameters. At present paper, several modern instrumental earthquake catalogues in different spatial scale, temporal scale, and with different seismic activity background are studied, and R/S method is used to analyze the variation of range of seismic parameters such as earthquake frequency, and earthquake time interval. For different seismic parameters, the ratio of range to standard deviation — R/S is a power law function of the length of time, and the exponent H of power law is always greater than 0.5. As we know, H=0.5 is the characteristics of all ideal random processes. Our results indicate that earthquake series is not an ideal Poisson process, on the contrary, the earthquake as a phenomenon bears dual characteristics of randomicity and regularity, and the greater H departs from 0.5, the more regularity the time series will show, and vice versa. With time scale changing, one can give the conservative estimate of the fluctuation, which might occur in a relatively long time scale, only by using the limited and known time records. Foundation item: State Natural Science Foundation of China (40074023).  相似文献   

计算条件对Hurst指数稳定性影响分析          下载免费PDF全文

赵翠萍  王海涛 《地震工程学报》2002,24(1):34-41

基于随机poisson分布模型和Gutenberg Richter关系 ,构造出 2 0年尺度内 8组样本量从 1 0 0 0到 1 50 0 0的模拟地震目录数据 ,以讨论样本量条件、最大拟合窗长τmax 等计算条件对地震活动频次序列H值计算结果的影响 .结果表明 ,随着样本量的增加 ,H值整体精度及稳定性增大 .当τmax =3 0 0时 ,表现尤为明显 .实际震例计算结果也表明 ,通过合理选取计算条件 ,可以较好地提取强震前H值的异常变化过程  相似文献   

地震频次的Hurst指数在地震预报中的应用   总被引：1，自引：0，他引：1  

郭德科 《华北地震科学》2002,20(3):44-50

引用Hurst指数，对华北地区18次中强地震前地震活动频次的Hurst指数进行了分析和研究，总结出了中强地震前地震活动频次的Hurst指数H值的异常主化特征，同时，把该方法应用到了河南及邻区中等地震预报研究中，制定了预报规则，进行了预测内符检验和预报评分，结果表明，该方法是一种有效的中短期地震预报方法，具有推广应用价值。  相似文献   

Application of the value of nonlinear parameters H and Δ H in strong earthquake prediction     

Pei-Yan Chen 《地震学报(英文版)》1997,10(2):181-191

In this paper, the relation that the curves of nonlinear parameter H and its difference ΔH bear with strong earthquakes in North China has been studied. First, the RSH algorithm has been applied to the North China region; the schemes of six quantitative prediction indexes have been studied in detail and then tested by tracing-back predictions. The result shows that all the six prediction schemes are of certain prediction efficiency and have passed the test. Among the six schemes, A and E are of the best effect, with correlation coefficients R of 0.47 and 0.48 respectively. We recommend these two schemes for practical use in prediction in the future. Furthermore, the relation between the curve of ΔH (the difference of H) and strong earthquake has been studied. Based on the above results, the RSΔH algorithm that uses the ΔH value to predict strong earthquake has been put forward and applied to predict strong earthquakes in North China. The correlation coefficient R of tracing-back prediction by this method is 0.45; this means that this method is also of better prediction efficiency. A combined application of these two algorithms has also been proposed. By the combined method, the time length spanned by false predictions can be shortened and thus the R value can be raised. Contribution No. 96A0033, Institute of Geophysics, SSB, China. This project sponsored by the Chinese Joint Seismological Science Foundation.  相似文献   

Application　of　the　value　of　nonlinear　parameters　H　and　ΔH　in　strong　earthquake　prediction     

陈佩燕 《地震学报(英文版)》1997,(2)

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基于Hurst系数的流域降雨时空变异分析方法   总被引：2，自引：0，他引：2  

谢平  雷红富  陈广才  李晶 《水文》2008,28(5)

基于Hurst系数能够反映水文序列长期相关性的原理,结合R/S分析方法和分数布朗运动理论,提出一种从整体上识别与检验时间序列变异及其变异程度的分析方法.该法将变异程度划分为4个等级:无变异(或弱变异)、中变异、强变异、巨变异;结合GIS空间分析方法,进而建立降雨量的时空变异分布图.应用该法对无定河流域年降雨序列进行时空变异分析,结果表明无定河流域大部分面积上的年降雨序列处于无变异或弱变异状态,但也有部分地区如高镇一带处于中变异状态,而且年降雨量有减少的趋势,该结论对于无定河流域的沙漠化治理、水土保持规划、水资源规划等具有重要的指导意义.  相似文献   

基于 EEMD 和 Husrt 指数的 GNSS 基准站的垂向速率估计     

彭葳  戴吾蛟 《测绘工程》2016,25(4):60-65

连续的全球卫星导航系统(GNSS)基准站的坐标时间序列中包含了复杂的噪声信号、非构造形变及其它因素的影响,尤其在垂直方向,对GNSS基准站在国际地球参考框架(ITRF)下的运动速率估计产生了较大的干扰。为进一步提高速率精度,文中采用整体模态分解(EEMD)方法对GNSS基准站的垂向观测时间序列进行分解,并根据各种信号的Hurst值进行分类及重构为噪声信号、季节性信号和长期趋势信号,采用最小二乘方法拟合长期趋势信号得到垂向速率。通过对中国大陆构造环境监测网络(CMONOC)的GNSS台站从2001—2013年近13a的垂向坐标时间序列的实例分析,采用基于EEMD和Husrt指数的最小二乘法能够准确地估计GNSS基准站的垂向速率。  相似文献   

地震活动性分析中余震的删除   总被引：13，自引：0，他引：13       下载免费PDF全文

陈凌  刘杰  陈颙  陈龙生 《地球物理学报》1998,41(Z1):244-252

介绍了几种删除余震的方法,并从地震断层的角度,提出了一种删除余震的新的震级相关时空窗法．采用这些方法,分别对4个具有不同时空尺度的地震目录删除了余震,并对原始目录及删除余震后的目录作了频度统计和R／S分析结果表明删除余震后,地震时间过程的平稳性明显提高,地震事件的独立性增强但仍存在着一定的非随机因素,主要表现在对地震时问过程的R／S分析中,Haret指数H＞0．5．在此基础上,进一步讨论了删除余震方法及其有效性的检验．  相似文献