������������ϵ��Ӧ������ת��   总被引：3，自引：2，他引：1  

刘序俨  黄声明  梁全强 《大地测量与地球动力学》2008,28(2):71-76

????κ??????????????????е???????????????????????????????е???????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????ITRF??WGS84????????????????????????  相似文献   

天山地震带主要活动断层现今的滑动速率及其地震矩亏损     

朱爽  梁洪宝  魏文薪  李经纬 《地震地质》2021,43(1):249-261

文中收集了1999—2015年天山地震带及其周边地区的GNSS数据,计算得到了速度场结果,并利用弹性块体模型计算了研究区域内各块体的闭锁深度和主要断层的滑动速率.研究结果表明:南天山断裂带西段的迈丹断裂的缩短速率处于高值状态,达(-6.3±1.9)mm/a,高于南天山东段;北天山断裂带西段的缩短速率同样高于东段.利用主...  相似文献   

Three-dimensional discrete element method parallel computation of Cauchy stress distribution over granular materials     

Beichuan Yan  Richard A. Regueiro 《国际地质力学数值与分析法杂志》2019,43(5):974-1004

The paper presents Cauchy stress tensor computation over parallel grids of message passing interface (MPI) parallel three-dimensional (3D) discrete element method (DEM) simulations of granular materials, considering spherical and nonspherical particles. The stress tensor computation is studied for quasi-static and dynamic conditions, and its resulting symmetry or asymmetry is discussed within the context of classical continuum mechanics (CCM), granular materials mechanics (GMM), and micropolar continuum mechanics (MCM). The average Cauchy stress tensor computation follows Bagi's and Nicot's formulations and is verified within MPI parallel 3D DEM simulations involving dynamically adaptive compute grids. These grids allow calculation of temporal and spatial distributions of stress across granular materials under static and dynamic conditions. The vertical stress component in gravitationally deposited particle assemblies exhibits nonuniform spatial distributions under static equilibrium, and its zone of maximum value changes during the process of gravitational pluviation and collapse. These phenomena reveal a microstructural effect on stress distribution within granular materials that is attributed to their discrete particulate nature (particle size, shape, gradation, boundary conditions, etc).  相似文献   

In-situ IR measurements of OH species in quartz at high temperatures   总被引：1，自引：0，他引：1  

S. Suzuki  S. Nakashima 《Physics and Chemistry of Minerals》1999,26(3):217-225

The nature of OH species in natural clear quartz was investigated by means of in-situ IR measurements over the temperature range –185 to 1000 °C. Reversible thermal behavior of OH species was examined for a sample pre-heated to 1000 °C for 1 hour. At room temperature, the IR spectrum of the quartz sample examined includes an intense absorption peak at 3379 cm^–1 which has been assigned to an OH stretching vibration associated with Al substituting for Si (OH(Al)). The major spectral changes of the OH(Al) bond involve a systematic shift of its peak position and a decrease in its integral absorbance with temperature. A quasi-linear increase of the peak position from –185 to 400 °C is interpreted to be due to the change in the vibrational frequency of OH(Al) with hydrogen bond (H bond) distance. At higher temperatures, the IR frequency shows only a slight change, indicating a small influence of the H bond. On the other hand, the gradual decrease of the integral absorbance of OH(Al) with temperature indicates a decrease of this defect’s molar absorptivity without any reduction in defect concentration. This is interpreted to result from a decrease in dipole moment of OH(Al) with temperature. A sudden shift of the vibrational frequency from 3396 to 3386 cm^–1 between 550 and 560 °C and a constant value of the integral absorbance from 535 to 570 °C were considered to be related to the change in H bond distance during the structural transformation of α-quartz to its β-form. The local environment of OH(Al) begins to change at temperatures below 570 °C, where the crystallographic α–β transition occurs. Received: 18 February 1998/ Accepted: 10 July 1998  相似文献   

Large-scale in situ permeability tensor of rocks from induced microseismicity   总被引：10，自引：0，他引：10  

Sergee A. Shapiro  Pascal Audigane  & Jean-Jacques Royer 《Geophysical Journal International》1999,137(1):207-213

  相似文献   

The 1996 June 17 Flores Sea and 1994 March 9 Fiji–Tonga earthquakes: source processes and deep earthquake mechanisms     

R. Tibi  C. H. Estabrook  & G. Bock 《Geophysical Journal International》1999,138(3):625-642

  相似文献   

Marginal Notes On Magnetotellurics   总被引：2，自引：0，他引：2  

M.N. Berdichevsky 《Surveys in Geophysics》1999,20(3-4):341-375

The paper presents the brief notes on some questionable points of modern magnetotellurics. These controversial points are: (1) nature and structure of the magnetotelluric impedance tensor, (2) magnetotelluric dispersion relations, (3) the magnetotelluric eigenstate problem, (4) separation of local and regional effects (the local-regional decomposition), (5) sensitivity of the TM and TE modes of the two-dimensional field, (6) robustness of the TM and TE modes, (7) identification and correction of the static shift, and (8) strategy of the two-dimensional interpretation: unimodal or bimodal inversion? Consideration of all these topics gives a better insight into problems and potentialities of magnetotellurics.  相似文献   

地震矩张量反演在地震观测报告中的应用   总被引：3，自引：0，他引：3  

刘瑞丰  陈培善  任克新  党京平  李保昆 《地震地磁观测与研究》1999,20(4):1-6

针对我国地震工作的实际需要,从１９９５年起,《中国地震台网目录和地震矩张量解》刊登了国内较大地震和全球大震的地震矩张量解和震源机制解。同时在《中国地震年报》上也刊登国内及邻区较大地震的地震长张量解和震源机制解。为了方便用户使用,本文对有关参数进行了说明。  相似文献   

关于DSX体系下的广义相对论（1PN）流体力学问题的探讨     

戴玉蓉  吴雪君 《天文学报》1999,40(4):400-406

使用ＤＳＸ 体系对于广义相对论（１ＰＮ） 的一般流体和理想流体均作了初步的探讨,建立了一种既适用于局部坐标系又适用于整体坐标系的解决广义相对论流体力学的新方法．对于一般流体,利用Ｍａｐｌｅ 软件计算了精确到ｃ－ ４ 项的能量动量张量Ｔａｂ 的结构,经过化简整理代到描述流体运动的基本方程中,得到了ＤＳＸ 体系下一般流体的基本方程,这是在局部坐标系中的结果,通过局部坐标和整体坐标之间的变换关系,可得整体坐标下物体的运动状态．另外,还给出了ＤＳＸ 体系下的理想流体力学的表示形式,通过将理想流体力学中一般的量改写为该体系下的量,从而改写了理想流体的Ｅｕｌｅｒ 方程和能量方程  相似文献   

一种白浪覆盖率与风要素关系模式   总被引：2，自引：0，他引：2  

郑桂珍  刘学海  徐德伦 《中国海洋大学学报(自然科学版)》1999,(4)

采用Ｇｌａｚｍ ａｎ 提出的“微尺度平均”的方法,在合理选择平均尺度的基础上计算了ＪＯＮＳＷＡＰ谱的四阶矩,并将此结果与Ｓｎｙｄｅｒ提出的白浪覆盖率模式结合,从而建立起依赖于风速和风区两者的半经验、半理论的白浪覆盖率与风要素关系模式。此模式给出的结果与Ｍｏｎａｈａｎ 等汇集的海洋白浪覆盖率测量数据总体符合良好。  相似文献