The equivalence of predictions from universal kriging and intrinsic random-function kriging

A proof is provided that the predictions obtained from kriging based on intrinsic random functions of orderk are identical to those obtained from anappropriate universal kriging model. This is a theoretical result based on known variability measures. It does not imply that people performing traditional universal kriging will get the same predictions as those using intrinsic random functions, because traditionally these methods differ in how variability is modeled. For intrinsic random functions, the same proof shows that predictions do not depend on the specific choice of the generalized covariance function. It is argued that the choice between these methods is really one of modeling and estimating the variability in the data.     

Conditioning of coefficient matrices of Ordinary Kriging

The solution of a set of linear equations is central to Ordinary Kriging. Computers are commonly applied because of the amount of data and work involved. There has, until recently, been little attention devoted toward the conditioning of kriging matrices. This article considers implications of conditioning upon numerical stability, instead of on robustness which has been the main focus of past work. The effect of properties of the stationary covariance matrix on the conditioning of the kriging matrix is discussed. The relationship between the covariance and autocorrelation functions allows some conclusions about the conditioning of covariance matrices, based on past work in deconvolution. The conditioning of some coefficient matrices of stationary kriging, defined in terms of either the semivariogram or the covariance, is examined.     

线性连续变化非弹性介质中地震波射线轨迹与走时研究

地球内部非弹性介质广泛存在,垂向线性连续变化非弹性介质模型具有重要理论与实际意义,本文利用复速度概念推导得到了复速度随深度线性连续变化的非弹性介质中地震波射线轨迹与等时线方程.理论结果表明:在线性连续变化非弹性介质中,射线轨迹呈圆形,等时面的形状为椭圆.最后对射线轨迹与等时线方程的适用性条件进行了讨论.     

甚高频时岩石介电常数的测试方法和特性

本文讨论20-200MHz频率范围内平行板电容法测量岩石介电常数和电导率的方法,指出常用的静电场公式的局限性,给出较精确的似稳场动态公式,并讨论20-50MHz频率范围内的岩石介电特性。     

长江三峡狮子口地区重力滑动构造研究

长江三峡工程坝址西南约１０ｋｍ的狮子口地区，发育一个长约８ｋｍ、宽约３ｋｍ的重力滑动构造系统。它由下伏系统、滑动系统和前缘推挤带构成，是一个典型的多层次滑褶型重力滑动构造。它形成时的温、压条件为１３０．５～１９３．７℃和１８０～２３０ＭＰａ；ｌ；形成深度约５～１０ｋｍ；总体岩层收缩量３２．２％；总滑移距离１０６０ｍ；活动时间上限１２７．６５士３８．２９万年。它是燕山运动期间南北向挤压体制下，在黄陵背斜东、西两侧应力屏蔽区内派生的近东西向拉伸构造应力场的产物。     

大同地震序列的震源机制解

使用ＣＤＳＮ长周期地震波形记录，利用Ｈｅｌｍｂｅｒｇｅｒ（１９６８）的广义地震射线理论得到的线性反演地震矩张量的方法，对１９８９年１０月１８日－１９９１年３月２５日发生在大同的４个Ｍｓ＞５．０的地震进行了反演，计算了这些地震矩张量和断层面解。     

结构平稳随机地震反应时域分析:方法

给出了三种常用的随机地震地面运动过程模型,即理想白噪声模型、金井清模型、改进金井清模型的相关函数表达式.引入状态向量,在状态空间中建立地震地面运动激励下的结构振动方程,并求解出结构的复模态特性和复模态反应.利用复模态叠加法推导出线性时不变多自由度体系在这三种随机地震动激励下的平稳协方差反应的解析式,可在时域内直接计算结构随机反应的统计特征.该方法物理概念清晰,结论简便明确,可作为实际工程结构平稳随机地震反应的实用分析方法.     

昆仑山口西8.1级地震地表破裂参数相互关系的新认识

地震地表破裂带调查表明,昆仑山口西 8. 1级地震的破裂长度为 426km,最大水平位移6m左右,地震破裂位移的分布明显地受断层活动段控制。该次地震的破裂长度远大于统计值,文中应用地壳极限线应变的概念,通过比较中国大陆内部几次走滑型强震的地震破裂最大位移与破裂长度的关系,论述了昆仑山口西 8. 1级地震中各次级段破裂的相对独立特征,认为该次强震不是一次整体性破裂事件,而是由连续触发的几次地震组成