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891.
Xu Shutong Jiang Laili Liu Yican Zhang Yong Institute of Geological Sciences of Anhui Province Hefei Anhui Sun Sheping 《《地质学报》英文版》1992,66(3):221-238
The Dabie Mountains are believed to be a collisional orogenic belt between the Yangtze amd Sino-Koreancontinental plates. It is composed of the foreland fold-thrust zone, the subducting cover and basement of theYangtze continental plate, the coesite- and diamond-bearing ultra-high pressure metamorphic zone and themeta-ophiolitic melange zone in the subducting basement, the fore-arc flysch nappe and the back thrust zoneoccurring respectively on the southern and northern margins of the Sino-Korean continental plate and the in-herited basin with molassic deposits on the northern margin. When the palaeo-Dabie oceanic plate subductednorthward in the Early Palaeozoic, volcanic arc and back arc basin probably formed on the southern margin ofthe Sino-Korean continental plate. The Sm / Nd isotopic dating of the strata and eclogite which were drawn in-to the foreland fold-thrust zone indicates that the intense collision of the two continental plates took place inthe Early Mesozoic. 相似文献
892.
信阳群的解体及其大地构造意义 总被引:26,自引:1,他引:26
通过对原信阳群标准地层剖面的深入研究,查明该岩石—地层单位实属变形十分复杂的构造地层体。古生物资料表明,原信阳群南湾组确属中—晚泥盆世地层;而同位素定年结果则显示,原信阳群龟山组纯系前泥盆纪变质杂岩组成的构造地层体。据此,笔者认为原信阳群应解体。本文着重从岩石、构造分析入手,对新解体出的不同地质体分别就其地层涵义、构造归属作了较系统的论述,并扼要阐明各自发展演化的大地构造意义。 相似文献
893.
TraveltimetomographyinversionandthedeepstructureofthesouthernTibetQING-TIANLU1)(吕庆田),MEI-JIANG1)(姜枚),KAI-YIMA1)(马开义),A.Hirn2... 相似文献
894.
He Daming Centre for Environmental Evolution Sustainable Development Yunnan Institute of Geography Kunming China Hsiang te Kung Memphis University TN USA 《地理学报(英文版)》1997,(4)
I.HydrogeographicalCharacteristicsTheLancangMekongRiveroriginatesfromasmallglacierof0.4km2inareaatanelevationof5167minLasaigongmaMountain(alsocalledZhaicuoMountain)atnorthernfootofTanggulaMountainRangewithinZaduoCounty,YushuTibetanAutonomousPrefecture,Qing… 相似文献
895.
A remarkable character of the Fangshan (房山) granodiorite isthe abundance of the large phenocrystic orthoclase perthite throughoutthe central part of the igenous body. They project on the weathered 相似文献
896.
A numerical model for shallow water flow has been developed based on the unsteady Reynolds-averaged Navier-Stokes equations with the hydrodynamic pressure instead of hydrostatic pressure assumption. The equations arc transformed into the a-coordinate system and the eddy viscosity is calculated with the standard k -ε turbulence model. The control volume method is used to discrete the equations, and the boundary conditions at the bed for shallow water models only include vertical diffusion terms expressed with wall functions. And the semi-implicit methed for pressure linked equation arithmetic is adopted to solve the equations. The model is applied to the 2D vertical plane flow of a current over two steep-sided trenches for which experiment data are available for comparison and good agreement is obtained. And the model is used to predicting the flow in a channel with a steep-sided submerged breakwater at the bottom, and the streamline is drawn. 相似文献
897.
898.
Mao Fangguan Lu Shunchang Luo Ruiren
Senior Engineer Naval Medical Research Institute P. L. A. of China Shanghai Senior Engineer Navigation Guarantee 《中国海洋工程》1995,(4)
The Diver Gas Recovery Installation (DGRI) was evaluated at 80 msw saturation - 100 msw excursion diving on HeO2 in the Naval Medical Research Institute (NMRI) of China in April, 1995. The diving depth, lockout time, breathing gas flow rate and consumption, inspired oxygen partial pressure (PO2) and carbon dioxide partial pressure (PCO2) were monitored. The results indicated that PO2 was controlled to fluctuate from 64.3 to 84.0 kPa and PCO2 went up from 0.01 kPa up to O.I kPa during 4 hours excursion diving; recovery of breathing gas reached 95%; three divers felt well and breathed comfortably during simulating heavy work. The test showed that it met desired performance goals. The DGRI is a kind of important equipment for long duration deep dive. It enables the gases exhaled by the divers to be re-cycled, and therefore it has great social, military and economic significance for diving operation and submarine rescue. 相似文献
899.
Based on the second-order random wave solutions of water wave equations in tinite water depth, statistical distributions of the depth-integrated local horizontal momentum components are derived by use of the characteristic function expansion method. The parameters involved in the distributions can be all detemained by the water depth and the wavenumber spectrum of ocean waves. As an illustrative example, a fully developed wind-generated sea is considered and the parameters are calculated for typical wind speeds and water depths by means of the Donelan and Pierson spectrum. The effects of nonlinearity and water depth on the distributions are also investigated. 相似文献
900.
南海海面温度的年际模态及其与季风强迫的关系 总被引:1,自引:0,他引:1
通过对COADS和OISST海洋气象资料的分析,以南海的海面温度异常(SSTA)为指示因子,在研究年际尺度上的南海与大尺度ENSO关系的基础上,进一步探讨了季风强迫下Ekman抽吸对SSTA年际变化的贡献。研究发现,南海SSTA滞后5个月时与:Nifio 3的SSTA相关系数最大,且其年际变化依方差贡献大小,分别有42.7月、25.6月及36.6个月的周期,这3个年际模态基本上能够描述海面温度的年际变异,为南海在大尺度ENSO背景下存在区域响应提供了重要的证据;应用Krause—Turner混合层温度方程对南海异常暖事件的研究表明,除了经向风应力异常,Ekman抽吸也是影响SSTA年际变异的主要因素,在某些异常年份甚至是主导因素,为南海SSTA年际变化的研究提供了重要的补充。 相似文献