Abrupt uplift of Tibetan Plateau at the end of early Pleistocene and Australasian impact event     

REN Shoumai  LIU Yongjiang  GE Xiaohong . Strategic Research Center of Oil & Gas Resources  Ministry of L  & Resources  Beijing  China . College of Earth Sciences  Jilin University  Changchun  China 《东北亚地学研究》2009,(3):145-155

The latest sharp uplift of the Tibetan Plateau and adjacent mountains occurred at the end of the early Pleistocene. The uplift of the Plateau resulted from Late Mesozoic-Cenozoic compressional structure due to the subduction of the Indian Plate beneath the Asian continent. This event definitively effected the formation of basin-mountain relief, Cenozoic basin deformation, large scale aridity and desertification of western China. The Australasian meteorites impact event happened ca. 0.8 Ma ago, located in the triangle area of the Indian Ocean ridge （20°S/67°E）. The impact may have resulted in an acceleration of speeding of the Indian Ocean ridge pushing the Indian Plate to subduct rapidly northward. Thus, the impact event can give reasonable explanation for the dynamic background of the latest rapid uplift of the Tibetan Plateau and the continental deformation of western China and even of the Middle Asia.  相似文献   

Dynamic Modeling and Investigation of Maneuver Characteristics of A Deep-Sea Manned Submarine Vehicle     

谢俊元  须文波  张华  徐鹏飞  崔维成 《中国海洋工程》2009,23(3):505-516

A deep-sea Manned Submarine Vehicle (MSV) is usually required to move at a low forward speed and a low rotational speed when it executes investigation tasks. In this condition, the motion is in large drift angles, and the maneuverability hydrodynamic forces cannot be expressed properly in the conventional mathematical model of submersible motion. In this paper, firstly, a general equation of MSV with six-freedom motion is presented, and the numerical simulation of descent/ascent motion and helix motion is c...  相似文献   

Distribution of Time-Averaged Suspended Sediment Concentration Due to Waves     

严冰  张庆河 《中国海洋工程》2009,23(1)

According to the mechanism of sediment suspension under waves,namely,the main reason of sediment suspension changes from the turbulent mixing in the bottom boundary layer to the periodic motion of the water particle near the free water surface,a three-hyer model d sediment concentration distribution due to waves is presented along the whole water depth based on the concept of the finite mixing |ength.The determination of the parameters in the model is discussed and an empirical formula is suggested.Comparisons between the calculated results and the measurements indicate that the resuits of the model agree well with the data from both the large and small scale flume experiments.  相似文献   

Fatigue Behaviour of Tubular Joints Made of China-Made Platform Steel     

Wang Gnanghai  Chen Bozhen Senior Research Engineer  China Ship Scientific Research Center 《中国海洋工程》1992,(1)

In China, a nationwide research program on fatigue behaviour of tubular joints made of China-made platform steel was carried out from 1983 to 1990, which was set by the Tubular Joint Research Committee for Offshore Structures (TJCOS) of China. This paper gives an outline of the basic properties of the China-made platform steel and fatigue test of tubular joints, including test specimens, test particulars and test results. A p-S-N curve based on the test results was established which reveals that the fatigue strength of tubular joints is fairly good. The thickness effect and effect of corrosion on fatigue strength in sea water are briefly discussed.  相似文献   

Analysis of groundwater recoverable resource by numerical method in Linfen Basin of Shanxi, North China     

Liping BAI    Yeyao WANG  Jinsheng WANG . Chinese Research Academy of Environmental Sciences  Beijing  China. College of Water Sciences  Beijing Normal University  Beijing  China 《东北亚地学研究》2008,11(3):168-173

Calculation of the groundwater recoverable resource is the main part of groundwater resource evaluation. The three-dimensional groundwater flow model in Linfen Basin was established by GMS software. Then the numerical model was calibrated by observed groundwater level from February to December in 2 000. Based on the calibrated model, the groundwater recoverable resource is calculated. The simulation result shows that under the given value of the groundwater recoverable resource, the groundwater level would decrease significantly in the first 1 000 days, while the water level would drop slowly in 1 000 to 2 000 days, and the water level change tend to be stable after 2000 days.  相似文献   

Application of ultrasonic CT method in nondestructive detection of interior defects in large scale concrete structural member of bridge     

Xiaopei ZHANG  Jianhui QIU  Jianjun NIU  Lizhi DU  Xuege WANG .College of Construction Engineering  Jilin university  Changchun  China.China Northeast Municipal Engineering Design  Research Institute  Changchun  China 《东北亚地学研究》2008,11(4):218-221

The ultrasonic computed tomography （USCT） method is derived from the basic principles of X-ray section scanning. This method records the arriving times of ultrasonic wave between the probes and the sources to ealculate the elastic wave velocity values in the section using the arrival times. Through analyzed the distribution Of elastic wave velocity in aim area, the information of the strength and the homogeneity of the investigated zone could be got indirectly. The authors introduced the operational principle of USCT and a practical case of using this method to detect the interior defects in large scale concrete structural member. Compared with other exploration methods, this method is more efficient and accurate.  相似文献   

Structural feature and tectonic evolution of Awati——Bachu area in Tarim Basin     

Zhihong LIU  Defeng ZHU  Junyi GAO  Xiangmei WUDongcheng LIN  Liguo ZHANG . Collage of Earth Sciences  Jilin University  Changchun  China. Exploration  Development Research Institute of Daqing Oilfield Company Ltd.  Daqing  Heilongjiang  China 《东北亚地学研究》2008,11(1):19-24

The research area is situated in the western part of Tarim basin, which includes Awati depression and Bachu uplifted block. It underwent three times processes of compression in a large scale and a near term extension since Cambrian. The first compression occurred during Middle Cambrian to Devonian, which formed fault band folds in NW axial direction. They were ＂under-water uplift＂ and distributed all over the research area. The second compression occurred in Late Permian and formed fault band folds and a few fault propagation folds in NS axial direction. They are developed near Tumuxiuke fault belt and the northern research area. The western anticline is bigger than the eastern one in extent and size. The third compression occurred during Palaeogene to Quaternary and formed tumuxiuke fault belt and fault propagation folds in NW direction. They are distributed over the south part of the research area. Tumuxiuke fault belt is a big scale dextral reversed strike-slip fault belt; it transformed or destroyed the fold structure of the research area. A short-term extension occurred during Early Permian. Tarim Basin is in the rift forming stage of craton, and there exist widespread basic vol- canic rocks, basic intrusive bodies and dikes.  相似文献   

Application of TSD tunnel seismic prediction system in karst area     

Lizhi DU  Xiaopei ZHANG  Jianjun NIU  Xuege WANG .College of Construction Engineering  Jilin University  Changchun  China.China Northeast Municipal Engineering Design  Research Institute  Changchun  China 《东北亚地学研究》2008,11(4):246-250

TSD is one of the classical methods of tunnel seismic prediction based on higher accuracy multi-wave multi-component seismology. The working principle of the TSD and an application example of the TSD on tunnel prediction in Chongqing are introduced in this paper. This system has two ports for speed signal and acceleration signal, and the equipment is more portable and easy to use. According to the application results we can conclude that the TSD prediction system is accurate and it has the wide application prospect in tunnel seismic detection.  相似文献   

青海省花岗岩类岩石谱系单位的划分方案     

刘恒福  金玉声  郝维杰 《青海国土经略》2000,(1)

依据同源岩浆演化理论和花岗岩类岩石等级体制的划分,将青海省侵入岩划分为13个构造岩石区;划分了108个超单位、117个(命名)单元(含7个独立单元)、255个岩性单元及数十个类型的年代加岩性侵入体。全省侵入岩成因初步分为幔源型、壳幔混合型、壳源深部型、壳源浅部型和浅壳源型;其分别形成于裂谷、深部裂冲、板块俯冲、板内挤压、板块碰撞及造山期后抬升环境。  相似文献   

Effects of salinity, light and temperature on growth rates of two species of Gracilaria (Rhodophyta)     

徐永健  韦玮  方建光 《中国海洋湖沼学报》2009,27(2)

Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32～C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24℃, 20 and 200 μmol/(m2.s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30℃, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38℃, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively.  相似文献