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141.
LIU Hailing SUN Yan GUO Lingzhi SHU Liangshu YANG Shukang ZHOU Di ZHANG YixiangEarth Science Department Nanjing University Nanjing Open Lab of Geology Palaeoenvironment of Marginal Seas South China Sea Institute of Oceanology Academia Sini Guangzhou 《《地质学报》英文版》1999,73(4):452-463
The Nansha ultra-crust layer-block is confined by ultra-crustal boundary faults of distinctive features, bordering the Kangtai-Shuangzi-Xiongnan extensional faulted zone on the north, the Baxian-Baram-Yoca-Cuyo nappe faulted zone on the south, the Wan'an-Natuna strike-slip tensional faulted zone on the west and the Mondoro-Panay strike-slip compressive faulted zone on the east. These faults take the top of the Nansha asthenosphere as their common detachmental surface. The Cenozoic dynamic process of the ultra-crust layer-block can be divided into four stages: K2-E21, during which the northern boundary faults extended, this ultra-crust layer-block was separated from the South China-Indosinian continental margin, the Palaeo-South China Sea subducted southwards and the Sibu accretion wedge was formed; E22-E31, during which the Southwest sub-sea basin extended and orogeny was active due to the collision of the Sibu accretion wedge; E32-N11, during which the central sub-sea basin extended, the Miri accretion 相似文献
142.
143.
ZHANG Xingnong YANG Hong SUN Bo
Senior Engineer River Harbour Engineering Department Nanjing Hydraulic Research Institute Nanjing P. R. China
Engineer River Harbour Engineering Department Nanjing Hydraulic Research Institute Nanjing P. R. China 《中国海洋工程》1999,(3)
Silt deposition occurs in the downstream approach,channel of the tidal lock as in a closed channelor excavated dock basin.It is often difficult to calculate or predict siltation because of complex flow and sedi-ment conditions and many other affecting factors.In this paper,the characteristics of flow movement in theapproach channel(including its mouth)of the tidal lock are analyzed,the basic laws of sediment movementand siltation mechanism are investigated,the conditions for three types of siltation(circumfluence siltation,density flow siltation and slow flow siltation)are discussed,and corresponding calculating formulas are pro-posed.A practical example shows that the difference between measured and calculated results is small,indi-cating that the present calculating methods could be used in design and management of practical engineeringprojects. 相似文献
144.
I.Tumwikirize 《中国地震研究》1999,(1)
For earthquake-prone countries of the world, it is crucial to develop countermeasures and to share experiences in seismic hazard mitigation. The measures for seismic hazard mitigation are related to many factors, e.g., social, economic, and political. Research focused on modern science and technology paves the way for a better understanding of the earthquake phenomenon and helps to plan against its effects in seismically active areas.In this paper, we consider some of the events that occurred in earthquake-prone countries, both developing and developed, which caused devastation to the society and economy. These are mainly major events that have affected a considerable portion of the gross domestic product of these economies.Measures to mitigate seismic hazard are stressed and suggested. In addition, experiences in seismic hazard mitigation in Uganda and the rest of the world are discussed in general terms. Attention is given to geotectonic settings as well as the work of seismic hazard and disaster mana 相似文献
145.
我国水资源开发利用业绩与前景 总被引:6,自引:0,他引:6
新中国成立以来,我国水利事业得到迅速发展,有效地促进了社会的进步与经济的繁荣。我国是世界上人均水资源贫乏的国家之一,如何实现水资源与社会,经济、环境的协调发展,实现水资源的可持续开发利用,仍将是我国可持续发展的关键问题之一。回顾了新中国成立以来水资源开发利用发展的阶段与过程,简要介绍了在水资源开发利用与保护方面的主要成就,较为系统地回顾和总结了我国水资源管理方面的主要工作,并对21世纪我国水资源可 相似文献
146.
ZHOU Liqing YANG Shengliang LEI YixinExploration Development Department East China Petroleum Bureau CNSPC South Rehe Rd. Xiaguan District Nanjing Jiangsu 《《地质学报》英文版》2000,74(3):674-679
In the Northern Jiangsu basin there are high pure CO2 gas pools, low condensed oil-containing CO2 gas pools, high condensed oil-containing CO2 gas pools and He-containing natural gas pools, with the δ13Cco2 (PDB) values ranging from -2.87‰ to -6.50‰, 3He/4He 3.71×10-6 to 6.42×10-6, R/Ra 2.64 to 4.5, 40Ar/36Ar 705 to 734, belonging to typical mantle source inorganic gas pools which are related to young magmatic activity. The gas layers occur in two major reservoir-caprock systems, the terrestrial Meso-Cenozoic clastic rock system and the marine Meso-Palaeozoic carbonate rock-clastic rock system. Controlled by the difference in the scale of traps in the two reservoir-caprock systems, large and medium-scale inorganic gas pools are formed in the marine Meso-Palaeozoic Group and only small ones are formed in the terrestrial Meso-Cenozoic strata. Inorganic gas pools in this basin are distributed along the two deep lithospheric faults on the west and south boundaries of the basin. Gas pools are developed 相似文献
147.
Bing Dong De-Qing Ren Xi Zhang Physics & Astronomy Department California State University Northridge CA - USA National Astronomical Observatories/Nanjing Institute of Astronomical Optics & Technology Chinese Academy of Sciences Nanjing China 《中国天文和天体物理学报》2011,(8)
An adaptive optics(AO) system based on a stochastic parallel gradient descent(SPGD) algorithm is proposed to reduce the speckle noises in the optical system of a stellar coronagraph in order to further improve the contrast. The principle of the SPGD algorithm is described briey and a metric suitable for point source imaging optimization is given. The feasibility and good performance of the SPGD algorithm is demonstrated by an experimental system featured with a 140-actuator deformable mirror and a Hartmann-... 相似文献
148.
Cambro-Ordovician rocks occur widely in Hsishan. In the westernenvirons of Peking some of the best exposures of these rocks can be observedin the Northern limb of the Chiulungshan (九山龙) syncline, which extends 相似文献
149.
下扬子地区沿江前陆盆地形成的构造控制 总被引:25,自引:0,他引:25
华北板块与扬子板块沿大别-胶南造山带的陆-陆碰撞使造 山带侧的扬子板块成为前陆变形带,并在其上发育了沿江前陆盆地。沿江前陆盆地初始继承性发育于下扬子区海退末期残留的陷区,随后于黄马青期受北界滁河断裂与南界江南断裂的对冲控制而成为双向压隐型盆地。 相似文献
150.
PAN Shaohua XIAQiyi LIN Shiqing XU Lunhuan
Professor Dept. of Coastal Engineering College of Harbour Waterway Coastal Engineering Hohai University Nanjing P. R. China.
Senior Engineer Dept. of Coastal Engineering College of Harbour Waterway Coastal Engineering Hohai University Nanjing P. R. China.
Senior Engineer Fujian Province Ports Shipping Administration Bureau Fuzhou P. R. China. 《中国海洋工程》1999,(2)
Test studies on the wave pressure on a breakwater pier show that the influence of transmissivewave pressure on the outside wall of the breakwater pier is considerable,when the width of the pier is notvery large.The variations of transmissive wave pressure on the breakwater pier with different widths arecompared and the relationship is obtained between relative transmitting distance b/L and wave pressurereduction factor K,which may be used in the design of similar breakwater piers. 相似文献