Structures of the Bohai Petroliferous Area, Bohai Bay Basin   总被引：3，自引：0，他引：3  

CAI Dongsheng  LUO Yuhui  YAO Changhu  Research Institute of the Bohai Corporation of CNOOC  Tianjin HE Jiankun  HU Shengbiao  Institute of Geology  Geophysics  Chinese Academy of Sciences  Beijing LU Huafu  WANG Liangshu Department of Earth Sciences  Nanjing University  Nanjing  Jiangsu 《《地质学报》英文版》2000,74(3):641-650

This paper, for the first time, deals with a more systematic study of the structures in the Bohaipetroliferous area that covers nearly one third of the Bohai Bay basin. The study mainly involves the effects of preexisting basement faults on the basin formation, the characteristics of basin geometry and kinetics, the modelling of the tectonic-thermal history, the polycyclicity and heterogeneity in the structural evolution and the natural seismic tomographic images of the crust and upper mantle. The authors analyze the features of the dynamic evolution of the basin in the paper and point out that the basin in the Bohai petroliferous area is an extensional pull-apart basin.  相似文献   

Non-linear density evolution from an improved spherical collapse model     

Sunu Engineer  Nissim Kanekar  T. Padmanabhan 《Monthly notices of the Royal Astronomical Society》2000,314(2):279-289

We investigate the evolution of non-linear density perturbations by taking into account the effects of deviations from spherical symmetry of a system. Starting from the standard spherical top hat model in which these effects are ignored, we introduce a physically motivated closure condition which specifies the dependence of the additional terms on the density contrast, δ . The modified equation can be used to model the behaviour of an overdense region over a sufficiently large range of δ . The key new idea is a Taylor series expansion in (1/ δ ) to model the non-linear epoch. We show that the modified equations quite generically lead to the formation of stable structures in which the gravitational collapse is halted at around the virial radius. The analysis also allows us to connect up the behaviour of individual overdense regions with the non-linear scaling relations satisfied by the two-point correlation function.  相似文献   

地下水位对定点形变观测干扰的抽水实验   总被引：3，自引：2，他引：3  

陈鹏  李正媛  刘妙龙  董洪军  陈嵩 《大地测量与地球动力学》2004,24(3):79-83

抽水所造成的地下水位的变化会即时在局部范围内造成地表的形变，干扰定点地壳形变观测。在蓟县地震台进行的抽水实验表明：这种干扰的幅度与抽水水井到形变监测仪器的距离有关，也和抽水水井水位的最大降深有关。根据实验数据得到了抽水对定点形变观测的影响范围的经验公式。  相似文献   

MODELING SEDIMENT PROCESSES ON SMALL WATERSHEDS:A CONCEPTUAL FRAMEWORK Ⅰ. BROAD SHALLOW FLOW PROCESSE     

Vicente L. LOPES Assistant Professor  School of Renewable Natural Resources  The University of Arizona  Tucson  Arizona  Peter F. FFOLLIOTT Professor  School of Renewable Natural Resources  The University of Arizona 《国际泥沙研究》1992,(3)

A conceptual modeling framework for developing process-based mathematical models of sediment generation, transport, and deposition on broad shallow flow areas is presented. The governing equations relevant to process-based modeling of broad shallow flow sediment processes on small watersheds are presented and the effects of space and time averaging on the predictive equations are described. Starting from the most general one-dimensional, unsteady model of sediment processes, simpler model structures are obtained and the successive simplifications made on the governing equations in order to obtain simpler and less detailed formulations are described. Specific model formulations are given for illustrative purposes and applications of these models to erosion and sediment yield prediction from broad shallow flow areas are shown using sediment data from rainfall simulator plots. In spite of some progress made in the development of process-based erosion and sediment yield models from broad shallow flow areas, further developmental modeling efforts must be based on a clear separation between hydrologic and hydraulic processes, and the soil properties which are significant for each.  相似文献   

Manned Testing of the Diver Gas Recovery Installation     

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   

Underwater Explosion Treatment of Marine Soft Foundation   总被引：11，自引：0，他引：11  

Zheng Zhemin  Yang Zhengsheng Jin Liu Professor  Academician of Chinese Academy of Sciences  Director of Mechanics Institute of Chinese Academy of Sciences  Beijing Professor  Mechanics Institute of Chinese Academy of Sciences  Beijing Senior Engineer  Lianyungang Harbor Construction Command Post  Lianyungang  Province of Jiangsu 《中国海洋工程》1991,(2)

The consolidation of soft foundation is a problem that commonly appears in harbor construction engineering on muddy coast. Introduced in this paper is the experimental study on underwater explosion treatment of soft foundation, including the regulations of explosion hollow development and medium movement, the law of similarity of densification and settlement of filled stone mass by shock wave pressure and explosion energy and their construction technologies, etc. A number of projects have been completed by applying this new technique, and the technique itself has been proved practicable.  相似文献   

Safety Level and Reliability Index for Bank Slope Stability     

Mai Yuanjian Senior Engineer  the th Harbour Engineering Bureau  The Ministry of Communications of P. R. China  Guangzhou 《中国海洋工程》1997,(2)

Based on statistics and analysis of the safety factor of unstable bank slopes,the relation be-tween safety level and reliability index of stability is studied and discussed,and then the elementary cali-brating calculation is carried out to the levels of safety and reliability for bank slope stability in the rangeof safety factors stipulated in existing China Technical Specifications for Port Engineering—FoundationPart(1987)and to those reached by some stable bank slopes already built.The results show that the relia-bility index β in the effective stress method is able to reach a high value of 2.4～4.1(mid-value 3.25),while the value of β in other three kinds of total stress method can just reach a lower value of 0.5～2.8(mid-value 1.65),which are in conformity with the engineering experience in China,and thus acceptable.Some suggestions are also given in this paper to the adoption of the value of β_0—objective reliability indexfor bank slope stability.  相似文献   

Water Wave Refraction and Diffraction over Frictional Topography     

Zuo Qihua  Yao Guoquan Ding Bingcan Senior Engineer  Nanjing Hydraulic Research Institute  Nanjing Engineer  Nanjing Hydraulic Research Institute  Nanjing 《中国海洋工程》1993,(1)

- This paper considers the effects of wave energy dissipation induced by sea-bottom friction on the computational results of water wave refraction and diffraction with the parabolic equation method. The presented results show that the friction factor formula adopted in this paper is of higher numerical accuracy than that introduced by Dalrymphe (1984), and it can be used to compute wave propagation over large open areas.  相似文献   

Reliability Index of Caisson Breakwaters for Load Variables Correlated   总被引：1，自引：0，他引：1  

郄禄文  李炎保 《中国海洋工程》2004,18(4):577-584

In order to suit the condition that the wave uplift is correlated with the horizontal wave load acting on a vertical breakwater, a generally used method for determining the reliability index β of the breakwater, i.e. the Hasofer-Lind method, is extended in a generalized stochastic space for correlative variables. The computational results for a caisson breakwater indicate that the value of β for the case of correlated variables is obviously smaller than that for the case of independent variables.  相似文献   

Numerical Study on the Probability of Fatigue Failure of a Semi-Submerged Platform Structure     

Yu Jianxing  Hu Yunchang  Wang Yehong  YuHongjie Associate Professor  Tianjin University  Tianjin  Professor  Tianjin University  Tianjin  Postgraduate for Master Degree  Tianjin University  Tianjin 《中国海洋工程》1994,(4)

On the basis of Miner's linear cumulative damage theorem, random variables are introduced to evaluate objectively the fatigue damage of a semi-submerged platform structure and a method is presented to analyze the fatigue reliability of the structure in its design life. The reliability of the method is verified through numerical examples and some conclusions are drawn, which have certain guiding and reference value for design and inspection.  相似文献