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141.
地震属性分析已广泛应用于河流相砂体预测并取得良好效果.地震属性分析技术主要包括属性提取、属性优选与属性融合,总结了河流相砂体预测中常见的地震属性提取方式、优选及融合方法,分析了由围岩干扰、地震分辨率限制导致的属性提取与分析误区,阐述了不同属性优选与融合方法的优缺点、适用条件与发展前景.总体而言,基于线性模型的地震属性融合提升效果较差,适用于少井区域;基于非线性模型的属性融合效果较好,但仅适用于钻井较多的地区,如油气开发阶段;无监督智能属性融合可应用于无井或少井区域,是未来无井或少井条件下属性融合的重要发展趋势之一.同时,重点阐述了新提出的分频属性融合与降低围岩干扰的属性融合方法. 相似文献
142.
鄂尔多斯盆地陇东地区长7段重力流砂体规模巨大、油气资源丰富,但不同层系不同地区砂体的形态、规模及叠置关系差异巨大,砂体构型特征及发育规律认识程度低,制约了其油气滚动勘探和开发效率。在岩心观察基础上,基于单井砂体构型界面识别和区域性连井砂体对比,结合砂体沉积微相类型开展了砂体构型划分和发育特征研究。研究认为陇东地区长7段重力流砂体规模较大,主要发育西南物源体系,其次为东北物源。发育典型的重力流水道—湖底扇沉积,可细分为侵蚀型水道、过渡型水道、沉积型水道、溢岸、沟道化朵叶体、板状朵叶体和浊积席状砂7种沉积微相。自三角洲前缘斜坡至深湖沉积中心,除砂体形态从条带状向扇形转换外,砂体规模、垂向叠置关系、横向迁移方式等构型特征亦呈现规律性变化,平面上呈现良好的分带性。在靠近三角洲前缘斜坡的近岸半深湖区,单砂体厚度小,呈孤立条带状分布,叠置关系以薄互层或单层型为主;向盆地内部,单砂体厚度增大,横向连通性增强,砂体叠置导致垂向连通性增强,逐渐向连续叠加型转化;靠近沉积中心地区,单砂体厚度略有减小,但横向连通性显著增强,连片性明显,呈间隔叠加型。综合分析认为,该区重力流砂体构型受控于重力流沉积微相、基准面旋回变化以及物源供给速率。 相似文献
143.
Yun-Ming Dong Lan-Wei Jia Xiao-Hong Zhao Yunnan Astronomical Observatory/National Astronomical Observatories Chinese Academy of Sciences Kunming Graduate University of Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2006,6(1):69-76
We investigated physical quantities including the spectrum,emission lines and pulse profiles expected from a uniform jet,a spherical fireball and the 1/Γ region (the portion of the spherical fireball with opening angle 1/Γ)in the prompt emission phase,after taking into consideration of the Doppler effect under the fireball frame- work.Our study shows that:a)for these physical quantities the spherical fireball and the uniform jets do not present obvious differences,so we cannot use these to distinguish a spherical fireball from a uniform jet;b)for the spherical fireball and a uniform jet,the observed quantities mainly come from the 1/Г region,so we can simply use the 1/Г region in approximate calculations;c)broadening of emission lines is a general phenomena,which mainly comes from the curvature effect;d)the 1/Γ region plays different roles in different frequency ranges,and the radiation from the 1/Γ region is greater in the higher than in the lower frequencies. 相似文献
144.
Xi-Liang Zhang Xiao-Bin Wang Li-Yun Zhang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming Graduate School of Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2006,6(6):729-732
We measured the light-curve of the asteroid (147) Protogeneia in November 2004, with a CCD detector attached to the 1-meter telescope at the Yunnan Observatory, China. The synodic period and maximum amplitude of (147) at this apparition are 7.852 hours and 0.25 mag, respectively. The value of a/b for (147), from a preliminary estimation, is not less than 1.26:1. 相似文献
145.
Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming Graduate School of Chinese Academy of sciences Beijing 《中国天文和天体物理学报》2006,6(6):680-688
Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrody-namic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory (WENO) scheme to fifth order accuracy in space. HLLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing (TVD) Runge-Kutta scheme. Extensive testing and comparison with schemes that require characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics. 相似文献
146.
Zhong-Quan Qu Shuai Wang Cheng-Lin Xu XiaoYu Zhang Ming-Guo Sun Chun-Lan Jin National Astronomical Observatories/Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming zqqu@vip.km.net Graduate School of the Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2005,5(4):426-432
We analyze the spectral line broadening of those magneto-sensitive lines in solar magnetized atmospheres. The broadening at the line wings is due to the increase of the effective width of energy levels involved in Zeeman splitting, and the broadening at the line core also originated in Zeeman splitting under the condition that the Zeeman components are mixed. Therefore, the magnetoinduced or Zeeman broadening take effects on the whole line. The observed Stokes parameter data in a sunspot and outside it acquired by Solar Stokes Spectrum Telescope (S3T) are analyzed for the demonstration of this mechanism, and the Zeeman broadening rates are calculated for FeI6302.5 under some assumptions. Our result shows that the broadening is increased as the magnetic field strength becomes stronger, but the rate of increase at the line core is decreased as the field strength increases, while the rate at the wing does not show such an obvious regularity. The broadening is more effective in the line core than in the wings. 相似文献
147.
本文运用区位、层位和生态经济理论,阐述平山县的发展战略目标、重点、布局及对策。 相似文献
148.
149.
The precise time step integration method proposed for linear time-invariant homogeneous dynamic systems can provide precise numerical results that approach an exact solution at the integration points. However, difficulty arises when the algorithm is used for non-homogeneous dynamic systems, due to the inverse matrix calculation and the simulation accuracy of the applied loading. By combining the Gaussian quadrature method and state space theory with the calculation technique of matrix exponential function in the precise time step integration method, a new modified precise time step integration method (e.g., an algorithm with an arbitrary order of accuracy) is proposed. In the new method, no inverse matrix calculation or simulation of the applied loading is needed, and the computing efficiency is improved. In particular, the proposed method is independent of the quality of the matrix H. If the matrix H is singular or nearly singular, the advantage of the method is remarkable. The numerical stability of the proposed algorithm is discussed and a numerical example is given to demonstrate the validity and efficiency of the algorithm. 相似文献
150.
KANG Dujuan & WANG Huijun . NZC/LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China . Environmental Fluid Mechanics Laboratory Stanford University Stanford CA USA 《中国科学D辑(英文版)》2005,48(12):2260-2266
Dust storm is a disastrous weather that can cause serious environmental consequences and hazards. It causes excessive soil mass and nutrient loss in source areas, and air pollution in deposition area, which result in bad influence on agriculture, industry, traffic, and peoples’ daily life[1-4]. Dust storm can also affect the thermal balance of planetary radiation and then lead to meso- to macroscale climatic modification[5-7]. North- west China and North China are two high-frequency centers … 相似文献