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71.
东海陆架盆地位于欧亚板块的东南缘和西太平洋活动大陆边缘,本文选取了东海陆架盆地主要凹陷的17条地震剖面,采用平衡剖面技术,计算了主要凹陷新生代不同演化阶段的伸展率和压缩率。分析表明,东海陆架盆地构造演化总体由西向东跃迁。晚白垩世至晚古新世东海陆架盆地裂陷中心在西部坳陷带,始新世东迁至东部坳陷带,上新世东迁至东海陆架盆地东侧的冲绳海槽盆地。古新世中后期东海陆架盆地西部坳陷带北侧昆山凹陷反转; 中新世东部坳陷带的西湖凹陷反转。东海陆架盆地西部坳陷带与东部坳陷带构造演化不同,证明了东海陆架盆地的东西分带。西部坳陷带北部的长江坳陷和南部的台北坳陷构造演化不同,东部坳陷带北部的西湖凹陷和南部的钓北凹陷构造演化不同,证明了东海陆架盆地的南北分块. 相似文献
72.
The Uplift of the Longmenshan Thrust Belt and Subsidence of the West Sichuan Foreland Basin 总被引:8,自引:0,他引:8
Liu Shugen Luo Zhili Dai Sulan Changlu Institute of Technology Chengdu Sichuan ChinaDennis Arne Dalhousie U niversity Canadaand C.J.L. Wilson Melbourne U niversity Australia Jiang M inxi 《《地质学报》英文版》1996,70(1):16-26
Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded that (l)the Songpan-Garze fold belt has uplifted at least by 3-4 km with an uplift rate of no less than 0.3-0.4 mm/a since 10 Ma B.P.; (2) the Longmenshan thrust nappe belt has uplifted at least by 5-6 km with an uplift rate of more than 0.5- 0.6 mm /a since 10 Ma B.P.; (3) the Longmenshan detachment belt has uplifted by 1 - 2 km at a rate of 0.016-0.032 mm/a since 60 Ma B.P.; (4) the West Sichuan foreland basin has uplifted by 1.7-3 km at a rate of 0.028-0.05 mm/a since 60 Ma B.P.; (5) the uplift rate of the area on the west side of the Beichuan-Yingxiu-Xiaoguanzi fault for the last 10 Ma is 40 times as much as that on its east side; (6) the uplifting of the the Songpan - Garze fold belt and the subsidence of the West Sichuan foreland basin 60 Ma ago exhibit a mirro-image correlation, i.e 相似文献
73.
彩色全息显示中液晶空间光调制器位相调制偏差的矫正方法 总被引:2,自引:0,他引:2
采用三基色激光照明并结合时分复用或空间复用技术,可实现基于液晶空间光调制器(LC-SLM)的彩色全息显示. 但由于在不同激光波长入射条件下LC-SLM的位相调制特性曲线不同,难以同时满足多波长入射条件下2π线性位相调制的要求,致使彩色全息再现结果受到共轭像和零级斑的干扰. 针对该问题,本文通过实验测试获得LC-SLM在不同波长入射时的位相调制特性曲线,并分析了RGB激光器各分量的位相调制特性曲线非线性偏差和调制幅度偏差对多阶位相型傅里叶变换相息图再现效果的影响. 根据"查表法"建立了各波长入射条件下满足2 相似文献
74.
Guang-Zhong Xie Luo-En Chen Huai-Zhen Li Li-Sheng Mao Hong Dai Zhao-Hua Xie Li Ma Shu-Bai Zhou National Astronomical Observatories Yunnan Observatory Chinese Academy of Science Kunming Yunnan Astrophysics Center Yunnan University Kunming Physics Department Yunnan Normal University Kunming Physics Department Yuxi Normal College Yuxi Graduate University of Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2005,5(5):463-470
Black hole mass is one of the fundamental physical parameters of active galactic nuclei (AGNs), for which many methods of estimation have been proposed. One set of methods assumes that the broad-line region (BLR) is gravitationally bound by the central black hole potential, so the black hole mass can be estimated from the orbital radius and the Doppler velocity. Another set of methods assumes the observed variability timescale is determined by the orbital timescale near the innermost stable orbit around the Schwarzschild black hole or the Kerr black hole, or by the characteristic timescale of the accretion disk. We collect a sample of 21 AGNs, for which the minimum variability timescales have been obtained and their black hole masses (Mσ) have been well estimated from the stellar velocity dispersion or the BLR size-luminosity relation. Using the minimum variability timescales we estimated the black hole masses for 21 objects by the three different methods, the results are denoted by Ms, Mk and Md, respectively. We compared each of them with Mσindividually and found that: (1) using the minimum variability timescale with the Kerr black hole theory leads to small differences between Mσand Mk, none exceeding one order of magnitude, and the mean difference between them is about 0.53 dex; (2) using the minimum variability timescale with the Schwarzschild black hole theory leads to somewhat larger difference between Mσand Ms: larger than one order of magnitude for 6 of the 21 sources, and the mean difference is 0.74 dex; (3) using the minimum variability timescale with the accretion disk theory leads to much larger differences between Mσand Md, for 13 of the 21 sources the differences are larger than two orders of magnitude; and the mean difference is as high as about 2.01 dex. 相似文献
75.
76.
青岛胶州湾地区重大工程建设项目设计的地质基础 总被引:3,自引:0,他引:3
本文以青岛胶州湾地区的基本地质条件为基础,分析研究了该地区地质基础对重大工程建设项目设计的影响,提出了青岛市重大工程项目设计的基本原则和对城市整体规划的具体建议。 相似文献
77.
78.
现代水下技术在我国水运工程建设中的应用与前景 总被引:1,自引:0,他引:1
自本世纪80年代中期以来,世界水下工程技术随着各国科学水平的提高而得以迅速发展。本文从水下工程技术的专业范畴及特征着手,分析了现代水下技术在水运工程建设中的应用;介绍了国外现代水下技术的基本进展及趋势;评价了国内水下工程技术及装备水平,同时展示了我院近十年来在现代水下技术与装备和开发、应用方面所做的工作与实力;最后分析了国内水运工程建设发展对水下技术的挑战,以及发展我国现代水下技术装备开发研究所面 相似文献
79.
80.
The multi-band data covering optical, X-ray and γ-ray energy regions of 130 Fermi blazars in the First LAT AGN Catalog (1LAC) were collected to investigate the broadband spectral properties. The composite spectral indices show that HBLs have convex optical-to-X-ray continua and concave X-ray-to-γ-ray continua, α γX γ >0 and α XOX ?<?0, while FSRQs and LBLs have α γX γ ?<?0. The α XOX distribution of FSRQs and LBLs extends from negative to positive values. We suggest α γX γ ?>?0 and α XOX ?<?0 could be considered as a criterion for HBLs. Moreover, HBLs have narrow distribution of peak interval of $\log\nu_{\rm p}^{\rm ic}-\log\nu_{\rm p}^{\rm syn}$ , and FSRQs have significant anti-correlation between $\log\nu_{\rm p}^{\rm ic}-\log\nu_{\rm p}^{\rm syn}$ and $\log\nu_{\rm p}^{\rm syn}$ . This indicates that SSC model is responsible for high energy emission of HBLs, while EC for FSRQs. Our results also indicate that FSRQs with larger break energy of electrons have smaller bulk Lorentz factor of dissipation region. 相似文献