临危不乱终脱险——记“大庆236”轮沉船事故

1983年10月6日18点30分,＂大庆236轮＂自秦皇岛满载15449吨原油驶往黄埔港,11日6点20分,该轮正航行在广东汕头附近海面上,此时,该海域正刮着6级大风,海面上海浪滔天。＂大庆236轮＂的驾驶员注意到了在＂大庆236＂后面偏左方向,有两艘船正在驶近，其中一艘集装箱船很快就超过“大庆236”轮驶遗了，另一艘船名为“克拉巴特山”的印度尼西亚货轮9点35分驶到“大庆236”轮左舷正横0．3海里处。     

SJT-5观察型潜水器冰下作业

无人遥控潜水器即ROV。本文的作者用简易的观察型ROV对大庆输油管线嫩江穿越管段的淤埋情况进行了冰下观察。本文对此次作业的方法、过程以及怎样保证ROV在高寒地区作业安全的措施作了介绍。这些有益的尝试和成功的经验,为严寒地区ROV的操作者提供了借鉴。     

大庆葡南地区AVO烃类检测应用研究

AVO(Amplitude Versus Offset)技术是利用叠前CDP道集,分析振幅随偏移距的变化规律,估算界面泊松比,推断地层岩性和含油气情况的一门物探新技术。以大庆的葡萄花地区为例,采用AVO技术对烃类进行检测,对天然气分布进行预测。     

海岸带地区可持续发展对策研究

一、海岸带特点和现状分析海岸带是海陆交互作用的特殊地带。海岸地区是人类生存和发展的摇篮。海岸带地区在人文、自然等方面都有其自身的特点，海岸带的现状是人类活动和自然演变共同作用的产物。在全球范围内，尤其是发展中国家，海岸带的特点和现状主要表现在以下几个方面。１海岸带的重要性海岸带地区在人类社会发展和文明进步的过程中具有特别重要的意义，海岸带的重要性体现在其对整个人类社会的生存和发展的极其重要的支撑作用。海岸带地区是人口密集、经济集中的发达地区，是人类生存和发展的精粹之地。近海岸带地区的沿海地带集…     

费歇判别法识别大孔道

根据测井曲线,运用费歇准则导出了识别砂岩油层大孔道的判别函数,判别函数是测井曲线的线性组合。利用此判别函数实现了在微机上用费歇方法识别大孔道的问题。针对大庆某地区一模型,取得了令人满意的结果,正确率达85%以上,结果表明,费歇判别法是识别大孔道的行之有效的方法。     

环珠江口岸区地理基础数据库研建分析

珠江口是珠江三角洲发展最快、环境压力最大而又最敏感的地区。建立该地区岸区地是基础数据库，可为地区环境变迁及可持续发展，规划和决策提供重要数字信息，是未来数字经济时代的必要要求，也是未来海区应急计划的重要组成部分。文章阐述了岸区数据库的基本结构、数据源、并介绍了数据库建立方法：指出了该数据的主要特点和重要意义。     

长江口拦门沙地区的泥沙运动规律

依据１９８８年７月和１２月水文观测资料，通过流，盐，沙的综合分析，认识到长江口拦门沙地区的泥沙运动有与河口其他地区不同的特点，泥沙输移在水平面上和垂直面上存在着多种循环，潮流和盐水截留大量泥沙积聚的拦门沙地区，河口在盐淡水交锋地带，除了涨，落急时段外，发现在转流时期泥沙也可能产生再悬浮，从而形成一个潮周期中出现３次或４次再悬浮的特殊规律。     

珠海地区风暴潮灾害特点及防潮减灾措施分析

本文分析了珠海地区风暴潮的成因、特点及其危害，指出了珠海地区的风暴潮灾害与台风路径、地形、洪水等多种因素有关，并提出了相应的减灾对策。     

黄河源地区水文水资源及生态环境变化研究

本文通过实地查勘调查、依据多年积累的原型观测资料，在分析可源地区基本情况、水文气候特征的基础上，揭示了近年来黄河源地区水文水资源及生态环境变化的特点；解答了这种变化所产生的结果和影响；得出了在河源地区封山育林植草，涵养水源，防止水土流失的初步对策；提出了河源地区水资源开发利用纳入全河统一调度、开发、利用规划的建议；以期找出对付生态环境恶化的根本途径。     

我国油气资源战略选区调查喜获成果

从2010年1月16--17日国土资源部在北京组织召开的全国油气资源战略选区调查与评价项目评审验收会上获悉，我国在南海北部、南黄海、大庆盆地外围油气资源战略调查中取得一批新成果。     

宽带波浪载荷下海洋结构物内应力范围及疲劳损伤分析

研究短期海况中海洋结构物在宽带波浪载荷作用下交变应力过程中的应力范围的概率分布及结构疲劳损伤问题.首先从应力的功率谱密度出发,利用小波变换作为工具,对应力过程进行模拟.然后用雨流计数法识别出应力过程中对结构造成疲劳损伤的应力范围,并用Weibull分布对应力范围的分布进行了拟合;最后给出了应力范围服从Weibull分布时结构疲劳损伤的计算方法.     

Experimental Research on Boundary Shear Stress in Typical Meandering Channel

A novel instrument named Micro-Electro-Mechanical System (MEMS) flexible hot-film shear stress sensor was used to study the boundary shear stress distribution in the generalized natural meandering open channel, and the mean sidewall shear stress distribution along the meandering channel, and the lateral boundary shear stress distribution in the typical cross-section of the meandering channel was analysed. Based on the measurement of the boundary shear stress, a semi-empirical semi-theoretical computing approach of the boundary shear stress was derived including the effects of the secondary flow, sidewall roughness factor, eddy viscosity and the additional Reynolds stress, and more importantly, for the first time, it combined the effects of the cross-section central angle and the Reynolds number into the expressions. Afterwards, a comparison between the previous research and this study was developed. Following the result, we found that the semi-empirical semi-theoretical boundary shear stress distribution algorithm can predict the boundary shear stress distribution precisely. Finally, a single factor analysis was conducted on the relationship between the average sidewall shear stress on the convex and concave bank and the flow rate, water depth, slope ratio, or the cross-section central angle of the open channel bend. The functional relationship with each of the above factors was established, and then the distance from the location of the extreme sidewall shear stress to the bottom of the open channel was deduced based on the statistical theory.     

波浪作用下斜坡上护面块体内部应力分布数值模拟

基于3D FEMDEM方法建立三维原型尺度数值模型,模拟波浪荷载作用下斜坡上护面块体内部的应力分布。波浪作用下结构物的水动力荷载采用微幅波理论模拟,护面块体之间的运动、碰撞接触以及块体内部的应力变化采用3D FEMDEM方法模拟。块体之间的接触力采用基于势函数的罚函数法计算,有限元的变形采用中心差分的显式方法求解。应用该数值模型与ANSYS软件程序对自重作用下混凝土扭王字块的内部应力分布特性进行了比较分析,验证了数值模型应力计算的可行性和计算精度。通过数值模拟计算给出了波浪作用下斜坡上护面块体之间的相对运动和块体内部的应力分布及应力历时曲线,探讨了块体内部应力变化特性。     

Vertical Distribution of Tidal Flow Reynolds Stress in Shallow Sea

Based on the results of the tidal flow Reynolds stresses of the field observations,indoor experiments,and numerical models,the parabolic distribution of the tidal flow Reynolds stress is proposed and its coefficients are determined theoretically in this paper.Having been well verified with the field data and experimental data,the proposed distribution of Reynolds stress is also compared with numerical model results,and a good agreement is obtained,showing that this distribution can well reflect the basic features of Reynolds stress deviating from the linear distribution that is downward when the tidal flow is of acceleration,upward when the tidal flow is of deceleration.Its dynamics cause is also discussed preliminarily and the influence of the water depth is pointed out from the definition of Reynolds stress,turbulent generation,transmission,and so on.The established expression for the vertical distribution of the tidal flow Reynolds stress is not only simple and explicit,but can also well reflect the features of the tidal flow acceleration and deceleration for further study on the velocity profile of tidal flow.     

江苏近海潮流湍流切应力研究

潮流的流速分布和湍流切应力的分布密切相关。为了研究潮流湍流切应力的特征和变化规律,本文从潮流运动方程推导出随潮流呈周期性变化的湍流切应力随深度的分布表达式。从江苏近海现场实测流速剖面中计算得到一个潮周期内的湍流切应力的变化过程。通过将实测值与本文理论解的比较发现,计算值能很好地反映出实测值的变化特征,尤其是能正确地反映潮流在加速和减速过程中,湍流切应力偏离线性分布呈现上凹和下凹的现象,以及只有在加减速转换的时候切应力才呈现线性分布的特点。最后,通过分析湍流切应力振幅及相位沿水深的变化情况,认为反映潮流周期、涡粘性和水深之间关系的参数Ri是决定湍流切应力弯曲程度及分布形态的重要参数。对于近海潮流,水深是影响湍流切应力偏离线性程度的主要因素。     

Bottom friction beneath random waves

The effect of random waves on the bottom friction is studied by assuming that the wave motion is a stationary Gaussian narrow-band random process. The approach is also based on simple explicit friction coefficient formulas for sinusoidal waves. The probability distribution functions of the maximum bottom shear stress for laminar flow as well as smooth turbulent and rough turbulent flow are presented. The maximum bottom shear stress follows the Rayleigh distribution for laminar flow and the Weibull distribution for smooth turbulent and rough turbulent flow. Some characteristic statistical values of the maximum bottom shear stress for the three flow regimes are also given.     

Ocean-atmosphere momentum coupling in the Kuroshio Extension observed from space

Using a combination of Quick Scatterometer (QuikSCAT), Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E), and Lagrangian drifter measurements, we demonstrate that wind data alone are not sufficient to derive ocean surface stress (momentum flux) over mid-latitude ocean fronts, specifically the Kuroshio Extension. There was no continuous and large-scale stress measurement over ocean until the launch of the scatterometers. Stress had been derived from winds through a drag coefficient, and our concept of stress distribution may be largely influenced by our knowledge of wind distribution. QuikSCAT reveals that the variability of stress could be very different from wind. The spatial coherence between the magnitude of stress and sea surface temperature (SST), between the divergence of surface stress and the downwind SST gradient, and between the vorticity of stress and crosswind SST gradient, are the inherent characteristics of stress (turbulence production by buoyancy) that would exist even under a uniform wind field. The coherence between stress vorticity and SST gradient is masked by the rotation of ocean currents over the Kuroshio meanders. Surface stress rotates in the opposite direction to surface currents because stress is the vector difference between wind and current. The results are in agreement with a previous study of the Agulhas Extension and confirm the unique stress measuring capability of the scatterometer.     

Long-term distribution of seabed shear stresses beneath random waves

The long-term distribution of seabed shear stresses under random waves is presented. The approach combines short-term distribution of maximum bottom shear stresses with a joint frequency table of significant wave height and peak period. An example of application is given where the long-term probability of exceeding a given level of the maximum bottom shear stress in the central North Sea is presented. The example includes estimation of the return period of the critical shear stress for sheet flow conditions, as well as the bottom shear stresses associated with the 1, 10 and 100 years return periods.     

Numerical study of multi-period palaeotectonic stress fields in Lower Cambrian shale reservoirs and the prediction of fractures distribution: A case study of the Niutitang Formation in Feng'gang No. 3 block,South China

Fractures not only control the distribution of oil and gas reservoirs, but also are key points in the research of oil and gas reservoir development programmes. The tectonic fractures in the Lower Cambrian shale reservoirs in the Feng'gang No. 3 block are effective reservoir spaces for hydrocarbon accumulation, and these fractures are controlled by palaeotectonic stress fields. Therefore, quantitatively predicting the development and distribution of tectonic fractures in the Lower Cambrian shale reservoir is important for the exploration and exploitation of shale gas in the Feng'gang No. 3 block. In the present study, a reasonable geological, mechanical and mathematical model of the study area was established based on the faults systems interpreted from seismic data, fracture characteristics from drilling data, uniaxial and triaxial compression tests and experiments on the acoustic emissions (AE) of rocks. Then, a three-dimensional (3-D) finite element method is applied to simulate the palaeotectonic stress field with the superposition of the Yanshan and Himalayan movements and used to predict the fracture distribution. The simulation results indicate that the maximum principal stress value within the study area ranged from 269.97 MPa to 281.18 MPa, the minimum principal stress ranged from 58.29 MPa to 79.64 MPa, and the shear stress value ranged from 91.05 MPa to 106.21 MPa. The palaeotectonic stress field is controlled by the fault zone locations. The fracture development zones are mainly controlled by the tectonic stress fields and are located around the faults, at the end of the fault zones, at the inflection point and at the intersection of the fault zones.