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本文着重讨论了用空间大地测量(VLBI和SLR)实测数据解算现时板块运动参数的方法,推导了有关公式。根据作者的实践,阐述了应用中应注意的问题。 相似文献
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基于NNR-NUVEL-1A地球板块运动模型和ITRF2000地球参考架的三维VLBI站速度矢量,采用实测的VLBI基线长度变化率作为约束,重新估计了部分国际VLBI站的局部或区域性地壳的垂直形变,并与国际地球参考架ITRFs解和VLBI全球解GLB2003,VTRF2003和VTRF2005的结果进行了比较。结果表明,欧亚板块的URUMQI站和太平洋板块的KWAJAL26站,南极OHIGGINS站的垂直形变率、ITRFs解和VLBI全球解存在6-15mm/a的差异,北美YUMA站可能有15-31mm/a 的垂直形变率,而美国西部太平洋板块的San Francisco(PRESIDIO)站的垂直形变率还有待进一步的研究。此外,SC-VLBA,CRIMEA和EFLSBERG站的垂直形变率、ITRFs解和VLBI全球解的差约为1-6mm/a。用不同方法得到的VLBI站的水平形变率解有较好的一致性。 相似文献
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对2004年苏门答腊-安达曼岛地震的测地学机制讨论 总被引:1,自引:0,他引:1
采用GPS测地学观测资料,基于NUVEL-1A板块运动模型,分别估计和讨论了INDI板块与Burma微板块之间、AUST板块与Burma/SE EURA板块之间的聚敛率,以及INDI与AUST板块间的相对速率。结果显示,沿苏门答腊-尼科巴群岛和沿安达曼群岛两个阶段的地壳破裂分别与AUST板块和Burma板块间、INDI板块和Burma板块间的聚敛率密切相关,从板块运动学角度提供了解释整个苏门答腊-安达曼群岛地壳破裂带上板块间耦合由南向北递减观测结论的佐证;在NUVEL-1A板块运动模型的背景下,2004年苏门答腊-安达曼岛主震应当为AUST板块相对于Burma/SE EURA板块以近60 mm/a,方向NE 30°~35°的运动所致,而非INDI板块或印-澳(INDI-AUST)板块运动所致;根据2004年苏门答腊-安达曼岛地壳破裂特征并结合其余震的分布,进一步肯定了AUST板块西北边界带的地质位置分布。 相似文献
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差分像运动视宁度测量实验 总被引:1,自引:0,他引:1
本文首先阐明了Fried参数(大气相干长度)r0的物理含义及为什么选取r0作为表征大气视宁度的参数;然后介绍了一种优良的测量r0的方法-差分像运动法,总结了该方法的六个特点,最后给出了在云南天文台用该方法的六个特点,最后给出了在云南天文台用该方法两次实测大气视宁度的实验结果及实验参数,并对结果进行了分析。 相似文献
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印、澳板块边界分布与GPS资料用于对2004年Sumatra-Andaman岛地壳破裂测地学机制的再讨论 总被引:1,自引:0,他引:1
杨志根 《中国科学院上海天文台年刊》2007,(1):30-36
基于作者此前对印度尼西亚苏门答腊-安达曼岛地震测地学机制的讨论,进一步根据McCloskey等人应用的INDI板块与AUST板块之间大致呈SW(≈S5)-NE(≈N2)走向的板块边界划分模型,利用GPS站速度资料,估计了沿整个苏门答腊-尼科巴岛地壳破裂带INDI板块与Burma/SEEURA板块之间的板块聚敛率,并与基于NUVEL-1A模型的INDI、AUST板块边界的分布所估计的AUST板块与Burma/SEEURA板块问聚敛率结果作了比较;根据2004年印尼苏门答腊-安达曼岛地壳破裂特征,对该地壳破裂的测地学机制作了进一步讨论,认为基于NUVEL-1A模型的INDI、AUST板块边界分布条件下地壳破裂的测地学机制讨论和2004年主震由AUST板块运动触发的结论可能更符合2004年地壳破裂事件的观测结论。目前的Burma微板块的欧拉旋转参数可能不适合用于对该次地壳破裂事件的测地学估计和机制的讨论;INDI、AUST板块间的相对运动是这两者板块间造山带的主要动力源。 相似文献
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基于ITRF2000的全球板块运动模型 总被引:3,自引:0,他引:3
利用最新国际地球自转服务 (IERS)发表的国际地球参考架ITRF2 0 0 0速度场 ,建立一个完全基于现代空间大地测量实测结果的现今全球板块运动模型ITRF2 0 0 0VEL。板块的总角动量 |L| =0 .12 7sr M·a-1,即ITRF2 0 0 0不满足无整体旋转的要求 ,与协议地球参考架CTRF定义不符 ,存在整体性旋转 相似文献
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完全基于空间大地测量数据,得出全球活动构造板块边缘相对运动速度、板块间运动类型、南半球膨胀、北半球压缩以及GPS垂向运动季节性变化振幅和相位随纬度的分布等,由此得出全球构造分布定量特征;全球构造在空间位置和几何形态上相互对称,而构造特征性质相反-即全球构造非对称性。 相似文献
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The study of the possible shapes of orbits of globular clusters of stars is closely connected with problems of studying the processes of formation and evolution of stars. The main difficulty in studying the orbits of these objects is the incompleteness of the information about the initial conditions of the motion, in particular the nearly complete absence of observational material on the proper motions of globular clusters. For that reason the study of the motion of these objects by direct dynamic methods has not yet succeeded. In such conditions it is necessary to resort to statistical methods developed by Edmondson and Von Hoerner, which make it possible to draw certain conclusions about the possible shapes of orbits of globular clusters on the basis of the Newtonian point-mass model.The purpose of this paper is to test the results of investigations of other authors against the latest observational data on globular clusters of stars and to develop the method itself further.Translated fromAstrofizika, Vol. 37, No. 4, 1994. 相似文献
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V. A. Shefer 《Solar System Research》2010,44(2):152-165
We propose a new method for the determination of the preliminary orbit of a small celestial body using three pairs of its
angular coordinates in three moments of time. The method is based on the use of the intermediate orbit we constructed earlier
using three position vectors and the corresponding time moments. This intermediate orbit accounts for the main part of the
perturbations of the motion of the body under study. We compare the results obtained by the classical Lagrange-Gauss method,
Herrick-Gibbs method, generalized Herrick-Gibbs method, and the new method by the examples of the determination of the orbit
of the small planet 1566 Icarus. The comparison showed that the new method is a highly efficient tool for the study of perturbed
motion. It is especially efficient when applied to high-precision observational data covering short arcs of the orbit. 相似文献
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We study the unsteady free-convection flow near a moving infinite flat plate in a totating medium by imposing a time-dependent perturbation on a constant plate temperature. The temperatures involved are assumed to be very large so that radiative heat transfer is significant, which renders the problem very nonlinear even on the assumption of a differential approximation for the radiative flux. When the perturbation is small, the transient flow is tackled by the Laplace transform technique. Complete first-order solutions are deduced for an impulsive motion. 相似文献
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We perform a study to describe motion of charged particles under the influence of electromagnetic and gravitational fields of a slowly rotating wormhole with nonvanishing magnetic moment. We present analytic expression for potentials of electromagnetic field for an axially symmetric slowly rotating magnetized wormholes. While addressing important issues regarding the subject, we compare our results of motion around black holes and wormholes in terms of the ratio of radii of event horizons of a black hole and of the throat of a wormhole. It is shown that both radial and circular motions of test bodies in the vicinity of a magnetized wormhole could give rise to a peculiar observational astrophysical phenomenon. 相似文献
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The free-convection flow of an incompressible viscous fluid past an infinite, vertical plate for impulsive as well as uniformly accelerated motion of the plate is discussed when the plate temperatuve varies as the square root of time. The Laplace transform technique is used to obtain the expressions for velocity and skin-friction. The influence of the various parameters, entering into problem, on the velocity field and skin-friction is extensively discussed. 相似文献
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Motion of the interplanetary dust particle under the action of collisions with much smaller interplanetary dust particles is investigated. The equation of motion is derived. Perturbation equations of celestial mechanics are also discussed. The results are compared with the Poynting-Robertson effect and the effect of solar wind on the motion of the interplanetary dust particles, from the point of view of observational data. 相似文献
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Empiric models of the Earth’s free core nutation 总被引:1,自引:0,他引:1
Z. M. Malkin 《Solar System Research》2007,41(6):492-497
Free core nutation (FCN) is the main factor that limits the accuracy of the modeling of the motion of Earth’s rotational axis in the celestial coordinate system. Several FCN models have been proposed. A comparative analysis is made of the known models including the model proposed by the author. The use of the FCN model is shown to substantially increase the accuracy of the modeling of Earth’s rotation. Furthermore, the FCN component extracted from the observed motion of Earth’s rotational axis is an important source for the study of the shape and rotation of the Earth’s core. A comparison of different FCN models has shown that the proposed model is better than other models if used to extract the geophysical signal (the amplitude and phase of FCN) from observational data. 相似文献
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Basant Kumar Jha 《Astrophysics and Space Science》1991,175(2):283-289
The effect of a uniform transverse magnetic field on the free-convection and mass-transform flow of an electrically-conducting fluid past an infinite vertical plate for uniformly accelerated motion of the plate through a porous medium is discussed. The magnetic lines of force are assumed to be fixed relative to the plate. Expression for the velocity field and skin-friction are obtained by the Laplace transform technique. The influence of the various parameters, entering into the problem, on the velocity field and skin-friction is extensively discussed. 相似文献
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Astrometric CCD observations of stars with large proper motions were carried out during 2008–2014 using telescopes of the Nikolaev Astronomical Observatory. A catalog of positions and proper motion of 1596 fast stars with proper motions exceeding 150 mas/yr has been compiled based on observation results. The catalog covers the declination zone from 0° to 65°. The standard error of derived proper motion is 1…10 mas/yr for both coordinates depending on the observational history of the star. Data from eight different star catalogs and surveys have been used to derive proper motion. The comparison results of proper motion with data from modern catalogs and results of the statistical test for the detection of possible invisible components are given. 相似文献