The MT inversion for conductivity anisotropy and EDA precursor, stress field and deformation band in the Earth’s deep crust

The conductivity anisotropy behaviour is described for certain environment in the Earth’s crust and the MT inversion method for a layered symmetrically anisotropic model is presented. The inversion interpretations of the anisotropic model from the observational data are helpful to identify the earthquake precusors as indicated by the deep conductivity anisotropic variations, and also provide some useful information to investigate the stress states and deformation bands in the deep crust of the Earth. This project is sponsored by the Chinese Joint Seismological Science Foundation.     

三分量地震波场的近似解析离散模拟技术

首先将二维各向异性介质中地震波动二阶偏微分方程组降为关于时间ｔ的一组一阶偏微分波动方程组，然后利用Ｔａｙｌｏｒ展式和插值逼近的方法构制了一种与有限元法、反射率法、射线追踪法、有限差分法等传统方法不同的近似解析离散方法（ＮＡＤＭ）．对双层各向同性介质以及横向各向同性介质中的三分量地震波场进行了模拟，并与传统的有限差分法作了比较，结果表明ＮＡＤＭ算法可行．     

桩贯入地基过程的动画仿真

本文通过三维显式有限元计算结果，对混凝土桩打基的过程进行了三堆动力反应分析，褡完成了此过程的动画仿真研究，研制成可携带的录相带工匠仿真动画，形象，生动，直观地再现了桩贯入地基过程中撞击波在桩体，地基中的传播，桩体与地基间的相对接触，滑移及桩锤与桩头部间的接触撞击过程。     

地电阻率各向异性度前兆特征与地震流体动态响应

以唐山地震为例，研究分析了孕震过程中地电阻率各向异性度Ｓ的变化及其特征，同时用“流体－地电”的观战对Ｓ的变化进行了物理解释。结果表明，地电阻率各赂异性度有可能成为一种新的地震地电前兆因子。     

计算层状介质中轴对称柱面瑞利面波频散函数的δ矩阵法

笔者将δ矩阵法应用于计算层状介质中轴对称柱面瑞利面波的频散函数,得到了六阶δ矩阵法、五阶δ矩阵法、快速δ矩阵法3种方法,很好地解决了高频数值精度丢失问题以及高频数值溢出问题,并提高了计算速度,数值计算及工程应用验证了上述方法的有效性,且表明了这些方法也完全适用于平面瑞利面波频散曲线的求取问题。     

Plastic deformation of wadsleyite: III. Interpretation of dislocations and slip systems

 Linear anisotropic elasticity has been applied to interpret the dislocation stability and ease of slip in wadsleyite. It is shown that wadsleyite is very isotropic from the elastic point of view. The influence of crystal chemistry and bonding on the choice of the slip plane is discussed. It is shown that slip is predominantly achieved on planes that do not shear Si–O bonds. It is suggested that dissociation of dislocations is essential in determining the ease of slip among the various slip systems. Received: 15 July 2002 / Accepted: 14 February 2003 Acknowledgements High-pressure experiments were performed at the Bayerisches Geoinstitut under the EU IHP – Access to Research Infrastructures Programme (Contract no. HPRI-1999-CT-00004 to D.C. Rubie). Enlightening discussions with A. Coujou and J. Rabier are gratefully acknowledged.