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981.
本文在活断层研究和地震宏观调查的基础上,从现代地壳运动特征及活动断层几何学,运动特征等方面研究了1932年麻城Ms6.0级地震的蕴育环境条件,为预测该区强震的地点和强度提供依据。 相似文献
982.
1IntroductionWestern Linyi of Shandong Province is one of the most important gold ore mineralization concen-tration areas. Tongjing skarn type gold copper de-posit, Jinchang skarn type gold copper deposit and Duijinshan porphyry type gold deposit were found in 1960's (Edited committee, 1996). Following the discovery of Guilaizhuang gold ore deposit related to alkaline rocks in 1988, the western Linyi region becomes one of the extensively studied areas of gold deposits in China (Lin etal.,… 相似文献
983.
本文采用R矩阵传播方法,通过求解CS近似下的耦合方程,计算了星际分子云条件下正-NH3分子和He碰撞的超精细跃迁碰撞截面和速率系数,为研究天体的信息提供需用的基础数据。 相似文献
984.
In this paper, the coupling schemes of atmosphere-ocean climate models are discussed with one-dimensional advection equations.
The convergence and stability for synchronous and asynchronous schemes are demonstrated and compared.
Conclusions inferred from the analysis are given below. The synchronous scheme as well as the asynchronous-implicit scheme
in this model are stable for arbitrary integrating time intervals. The asynchronous explicit scheme is unstable under certain
conditions, which depend upon advection velocities and heat exchange parameters in the atmosphere and oceans. With both synchronous
and asynchronous stable schemes the discrete solutions converge to their unique exact ones. Advections in the atmosphere and
ocean accelerate the rate of convergence of the asynchronous-implicit scheme. It is suggusted that the asynchronous-implicit
coupling scheme is a stable and efficient method for most climatic simulations. 相似文献
985.
本文主要介绍沙赫(Shan,P.M.)公式,对二维任意倾斜地层的层速度计算的应用效果。依据实际地层剖面Φ、V、Z参数的可能变化,设计18个较为复杂的地层模型进行了大量试算,并与Dix公式计算结果作了对比,表明对任意倾斜地层应采用沙赫公式提取层速度才是适宜的。 相似文献
986.
In this paper, the atmosphere is divided into two regions which are governed by different equations. Furthermore, multiple-scale
method is used to obtain the Benjamin-Ono equation satisfied by the nonlinear Rossby wave in weak shear zonal flow. The equation
has algebraic solitary wave solution, and the stationary streamfunction fields in-ithe atmosphere are calculated by using
numerical method, and the results demonstrate that the stationary solution is antisymmetric dipoles with the anticyclone north
of the cyclone, and the structure is similar to the equivalent modon obtained by Mcwilliams (1980). Because the modon obtained
here is an algebraic solitary wave, the modon may be called “algebraic modon”, and the stationary algebraic modon is consistent
with observations of blocking pattern in the atmosphere. 相似文献
987.
988.
A new integrated measuring system with eight force-balance accelerometers is proposed to obtain a direct measurement of six degree-of freedom (DOF) ground motions, including three rotational and three actual translational acceleration components without gyroscopes. In the proposed measuring system, the relationship between the output from eight force-balance accelerometer and the six DOF motion of the measuring system under an earthquake are described by differential equations. These equations are derived from the positions and directions of the eight force-balance accelerometers in the measuring system. The third-order Runge-Kutta algorithm is used to guarantee the accuracy of the numerical calculation. All the algorithms used to compute the six DOF components of the ground motion are implemented in a real-time in Digital Signal Processor (DSP). The distortion of the measured results caused by position and direction errors of the accelerometers in the measuring system are reduced by multiplying a compensation coefficient C to the output and subtracting static zero drift from the measured results, respectively. 相似文献
989.
Strongly peraluminous granites of Mesozoic in Eastern Nanling Range,southern China: Petrogenesis and implications for tectonics 总被引:17,自引:5,他引:12
SUN Tao ZHOU Xinmin CHEN Peirong LI Huimin ZHOU Hongying WANG Zhicheng & SHEN Weizhou Department of Earth Sciences Nanjing University Nanjing China Tianjin Institute of Geology Mineral Resources China Geological Survey Tianjin China 《中国科学D辑(英文版)》2005,48(2):165-174
The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite±tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the 相似文献
990.