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1.
绝对地磁测量预报地震   总被引:3,自引:0,他引:3  
介绍一种称为地磁等变线预报法的地磁绝对测量预报地震的新的处理方法。该方法既可将全国分散的地磁台站联系起来,使原来不能发挥作用的台站起到应有的作用,也可避免校正长期变差异的麻烦,达到大台距台站之间可直接作差值图的目的。这样,可能为地磁绝对测量预报地震开辟一个新的途径,为该手段在预报地震中起到更大的作用创造一定的条件。  相似文献   

2.
介绍了利用Logistic回归进行地震危险性概率预测方法,对以新西兰地区相同时间段内地震活动性b值和等地震个数所覆盖空间区域的半径r为例,讨论了地震活动性参数的变化和强震发生的概率关系。研究表明,该地区强震发生的概率总体上与强震发生前一年半时间窗内的地震活动性资料计算的b值呈正相关关系,与r值呈负相关关系。该方法可以推广应用于研究其他异常分布和强震的概率统计关系。  相似文献   

3.
对南京地震台、新沂地震台和郫县地震台地电阻率观测资料变化特征及邻区4次MS 5.0以上地震反应进行研究,发现:同一台站、不同测向地电阻率的测值大小可能存在较大差异,测值大的测道地电阻率年变化较规则,往往具有更强的映震能力。  相似文献   

4.
Anapproachondynamicearthquakepredic┐tionbygeoresistivitymeasurementsHONG-KUIZHANG1))(张洪魁),QI-XINGSHEN2)(沈启兴),WEIWU1)(吴卫)YU-L...  相似文献   

5.
用文献(贺仲雄,1983)提出的一种模糊综合评判方法,对内蒙布特哈旗一带进行了地震年度预报研究。利用1971~1988年共18年观测资料作为样本资料,对后17年进行预报检验,取得了较好的结果。  相似文献   

6.
地震记录处理的一种新方法   总被引:1,自引:0,他引:1  
介绍了M icrosoftV isual C (VC )和M atlab相结合开发地震记录处理软件的一种新方法。VC 和M atlab相结合开发地震记录处理软件,减轻了编程人员的工作量,提高了软件的开发效率和处理能力,为此类软件的开发提供了一种方便灵活的实现方法。通过一简单地震记录处理程序的三种不同实现途径,详细讲述了VC 和M atlab的编译环境。三种不同实现途径分别是:(1)VC 中直接调用M atlab C 数学图形函数库生成独立可执行程序;(2)VC 调用M程序生成的C/C 代码生成独立可执行程序;(3)VC 调用M文件转换成的DLL(动态链接库)生成可执行程序。文章还对三种实现途径进行了优缺点的比较,为开发人员在具体开发时提供参考。  相似文献   

7.
Considering the fact that there is only one pair of fixed potential poles in one direction used to monitor the resistivity changes under the observatory station which may indicate process of earthquake preparation, based on the precondition that the resistivity structure is 1-dimensional under the observatory station, and by way of equivalent model put forward by the authors, this paper suggests a kind of method trying to separate the resistivity changes in deep layers from that of the shallow layer. Analysis shows that, to obtain the same measured data with the same array, any a multi-layered geo-electrical structure can be equivalently taken as a two-layered one, we call it equivalent model. In this paper, the resistivity and thickness of the upper layer of the equivalent model are equal to that of the first layer of the original one, the resistivity of the lower layer of the equivalent model is obtained with calculation according to the requirement of equivalence, its value is relevant with the resistivities and thicknesses of all layer of the original model except for the first one, so the resistivity change of the equivalent layer can indicate the synthetic effect of variation of all layers of the original model except for the first one. The primary research results show that this method can work well. Foundation item: Chinese Joint Seismological Science Foundation (100146).  相似文献   

8.
The acoustic Doppler velocimeter (ADV) measures three‐dimensional velocities in a small, remote sampling volume at high frequencies, however, these measurements incorporate errors that are intrinsic to the measurement technique. This paper demonstrates a new method for calculating the total measurement errors, including sampling errors, Doppler noise and errors due to velocity shear in the sampling volume associated with single‐point ADV measurements. This procedure incorporates both the effects of instrument configuration and the distribution of errors between velocity components for any probe orientation. It is shown that the ADV can characterize turbulent velocity fluctuations at frequencies up to the maximum sampling rate and that Reynolds shear stress errors are very small. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

9.
利用地震观测波形直达纵横波能量的差异,在时间域创建标志地震事件震源性质的新参量a,计算182个台站记录的24个地震事件的a值,并用以分析2017年9月3日敏感地区发生的地震事件性质。结果表明,判据a具有良好的震源性质依附效应,从而为地震与爆炸的识别引进了一种新方法。  相似文献   

10.
城市建构筑物地震损失预测研究   总被引:12,自引:0,他引:12  
本文提出了预测城市建构筑物在不同烈度下地震灾害损失的简易方法。首先分析了影响城市建构筑物抗震能力的3个因素——抗震设防情况、建筑年代和结构类型;然后提出了建构筑物抗震能力指数的概念,并确定了将上述3因素综合成建构筑物抗震能力指数的方法;最后利用“九五”期间所做的大中城市的震害预测结果统计回归出房屋抗震能力指数与地震灾害损失——人员伤亡、经济损失和震后恢复时间的关系。由此可以得到建构筑物在不同烈度下地震灾害损失的简易计算方法。  相似文献   

11.
A new method for dynamic inversion of anisotropic equations   总被引:1,自引:0,他引:1  
AnewmethodfordynamicinversionofanisotropicequationsDING-HUIYANG1)(杨顶辉)JI-WENTENG2)(滕吉文)ZHONG-JIEZHANG2)(张中杰)1)DepartmentofGe...  相似文献   

12.
基于已有震害矩阵模拟的群体震害预测方法研究   总被引:1,自引:6,他引:1  
本文提出了一种群体震害预测方法,根据已有建筑物震害预测结果或震害统计分析结果,按照影响建筑物抗震能力的主要因素,由普查资料统计出的建筑物各影响因素的建筑面积比例得出模拟震害矩阵与已知矩阵的贴近度,最后进行加权平均,建立具体预测对象群体建筑物的震害矩阵。  相似文献   

13.
ResearchonTSIPmethodformedium-termearthquakepredictionDe-YuHUANG(黄德瑜);Yuan-QingZHU(朱元清);YongCHEN(陈颙)andYingJI(季颖)(CentreforAn...  相似文献   

14.
A method for simultaneous determination of mixed model parameters,which have different physical dimensions or different responses to data,is presented.Mixed parameter estimation from observed data within a single model space shows instabilities and trade-offs of the solutions. We separate the model space into N-subspaces based on their physical properties or computational convenience and solve the N-subspaces systems by damped least-squares and singular-value decomposition. Since the condition number of each subsystem is smaller than that of the single global system,the approach can greatly increase the stability of the inversion. We also introduce different damping factors into the subsystems to reduce the tradeoffs between the different parameters. The damping factors depend on the conditioning of the subsystems and may be adequately chosen in a range from 0.1 % to 10 % of the largest singular value. We illustrate the method with an example of simultaneous determination of source history,source geometry,and hypocentral location from regional seismograms,although it is applicable to any geophysical inversion.  相似文献   

15.
The method of prediction of earthquake by using seismisity (MPES) is to make use of the message of earthquakes (including large, middle, small) in pre-period to predict large earthquake in post-period. Some better methods are presented in this paper which are selected among many means used in our country recent years. These methods are classified into six sets: 1. Method of spatial pattern; 2. Method of time process; 3. Method of seismic sequence; 4. Method of earthquake correlation; 5. Method of parameters of seismic source and medium; 6. Comprehensive method. Prediction effects of each method are evaluated with unique score. The value of each method, scoreR, are generally in a range between 0.3 and 0.6. This value only represents internal consistency, however, the ability of actual prediction belongs to the extensional effect, which is generally lower than the value of internal consistency. If the ability of actual prediction could be evaluated withR = 0.3, the ability of prediction of earthquake by seismicity will be stated as following: If most of earthquakes must be predicted, the warning time needs to take seventy percent of whole time period of prediction; If half earthquakes must be predicted, the warning time needs to take twenty percent of whole time period of prediction. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,15, 239–252, 1993.  相似文献   

16.
岩石物理的理论模拟和数值实验新方法   总被引:12,自引:13,他引:12       下载免费PDF全文
当代物理实验科学和计算机科学技术的巨大进步为岩石物理的理论和实验研究开辟了新的领域.在细胞自动机基础上发展起来的格子气自动机和格子玻尔滋曼方法就是这种技术进步的产物.本文讨论了格子气自动机的发展及其应用于研究多孔岩石微观孔隙结构对宏观导电特性影响的新方法. 我们开发的模拟多孔岩石导电特性的数值实验新方法,提供了一种可深入到从微观孔隙结构这个尺度上来考察具有复杂孔隙结构的,孔隙度小于10%的低孔、低渗岩石的宏观导电特性及其影响因素.研究表明:Archie 系数m,n并不是传统上的意义,研究各种不同条件下F-、I-Sw关系,结果显示非阿尔奇现象与孔隙介质中孔隙、骨架和流体的混合导电网络有关,得出新的饱和度计算公式.同时还研究了泥质含量和分布、电阻率各向异性对宏观导电特性的影响,提出适用于电阻率各向异性地层的F-、I-Sw的关系.本文最后探讨了应用格子气自动机和格子玻尔滋曼方法进行岩心渗流和核磁共振数值实验的新方法及其发展前景.  相似文献   

17.
核磁共振多回波串联合反演方法   总被引:4,自引:1,他引:4       下载免费PDF全文
提出一种核磁共振多回波串数据联合反演方法,分别对核磁共振孔隙度测量的两组回波串数据、变等待时间多回波串数据以及变回波间隔多回波串数据进行了处理.结果表明,这样处理得到的一维核磁共振T2分布不但连续,而且能够揭示短横向弛豫组分的细微特征,提高了核磁共振孔隙度的精度.处理变等待时间或变回波间隔下的多回波串数据,可以得到孔隙流体的 (T2, T1)或(T2, D) 二维核磁共振分布图.与一维核磁共振T2分布相比,二维核磁共振提高了识别流体的效果.  相似文献   

18.
接收函数方法及其新的进展   总被引:7,自引:2,他引:7  
远震P波波形数据中包含了大量地震台站下方地壳和上地幔速度间断面所产生的PS转换波及其多次反射波的信息,由此提取的接收函数是了解地壳上地幔速度细结构的重要步骤手段之一.最近几年,接收函数和面波联合反演方法获得了较大的成功,两种分别对两种波形进行拟合,对反演的速度结构提供了有效的约束.地震勘探中的一些成熟技术被引进接收函数的数据处理,使其可用于地壳和上地幔主要速度界面的侧向变化研究.为增强接收函数的信噪比,将不同事件提取的接收函数进行分类,按方位角进行叠加,可以反应一些速度界面的横向变化.接收函数方法可用于PS转换震相的剪切波分裂研究.泊松比是推测地球内部物质构成的有效参数之一.接收函数方法分离出的转换波为获取泊松比提供了一条行之有效的便捷途径,单一的地震台远震记录中转换波可以估计点位下面地壳Vp/Vs值.另一方面,一些最新的反演技术被引入接收函数的反演.例如,格子收索方法力图解决接收函数反演中的不稳定性和非唯一性问题,格子搜索设计比较容易地结合先验约束并保证搜索是全空间的,避免了使用任何初始模型.该方法能保证在格子的间隔和参数的限度内获得全局最小,该方法被用于中东、南美及临近地区的深部结构.相邻算法是基于计算几何的概念而构建的一种非线性反演方法.该方法避免了此前一些方法(遗传算法、模拟退火)的一些缺陷,如大量样本的舍弃、过多参数的引进等,该算法对我国的五大连池和腾冲火山区的深部结构的反演,以及滇西地区的深部动力学研究获得了良好的效果.  相似文献   

19.
A new method for spatio-temporal prediction of rainfall-induced landslide   总被引:4,自引:0,他引:4  
1 Introduction The landslides influences on the human society have become an environment difficult problem not able to be neglected, and according to the priority of harms, harms of landslides are only smaller than those from earthquakes in all sorts of natural hazards[1]. Landslide is part of rock mass, soil mass or their compound mass slides downward along a certain slid- ing surface under the actions of inner and external dy- namics, and it is one severe instability phenomenon of rock and s…  相似文献   

20.
A method for simultaneous determination of mixed model parameters, which have different physical dimensions or different responses to data, is presented. Mixed parameter estimation from observed data within a single model space shows instabilities and trade-offs of the solutions. We separate the model space into N-subspaces based on their physical properties or computational convenience and solve the N-subspaces systems by damped least-squares and singular-value decomposition. Since the condition number of each subsystem is smaller than that of the single global system, the approach can greatly increase the stability of the inversion. We also introduce different damping factors into the subsystems to reduce the trade-offs between the different parameters. The damping factors depend on the conditioning of the subsystems and may be adequately chosen in a range from 0.1 % to 10 % of the largest singular value. We illustrate the method with an example of simultaneous determination of source history, source geometry, and hypocentral location from regional seismograms, although it is applicable to any geophysical inversion.  相似文献   

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