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1.
Kela 2 Gas Field, with high formation pressure (74.35MPa), high pressure coefficient (2.022) and difficulty of potential test and evaluation, is the largest integrated proved dry gas reservoir in China so far and the principal source for West-East Gas Development Project. In order to correctly evaluate the elastic-plastic deformation of rocks caused by the pressure decline during production, some researches, as the experiment on reservoir sensitivity to stress of gas filed with abnormal high pressure, are made. By testing the rock mechanic properties, porosities and permeabilities at different temperature and pressure of 342 core samples from 5 wells in this area, the variations of petro-physical properties at changing pressure are analyzed, and the applicable inspection relationship is concluded. The average productivity curve with the reservoir sensitivity to stress is plotted on the basis of the research, integrated with the field-wide productivity equation. The knowledge lays a foundation for the gas well productivity evaluation in the field and the gas field development plan, and provides effective techniques and measures for basic research on the development of similar gas fields.  相似文献   
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High buildings or architectural complex in urban areas remarkably distort the urban surface wind fields. As the air flow approaches,local strong wind may appear around the buildings. The strong wind makes the pedestrians on sidewalks, entrances and terrace very uncomfortable and causes the pedestrian level wind environment problem. In this studies, hot-wire wind measurement, wind scouring in wind tunnel and numerical computation were carried out to evaluate the wind environment of tall buildings in the prevailing flow conditions in Beijing areas. The results obtained by three techniques were compared and mutually verified. The conclusions drawn from three approaches agree with each other. Also the advantages and limitations of each method were analyzed. It is suggested that the combination of different techniques may produce better assessment of wind environment around high buildings.  相似文献   
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Structure‐from‐Motion (SfM) photogrammetry is now used widely to study a range of earth surface processes and landforms, and is fast becoming a core tool in fluvial geomorphology. SfM photogrammetry allows extraction of topographic information and orthophotos from aerial imagery. However, one field where it is not yet widely used is that of river restoration. The characterisation of physical habitat conditions pre‐ and post‐restoration is critical for assessing project success, and SfM can be used easily and effectively for this purpose. In this paper we outline a workflow model for the application of SfM photogrammetry to collect topographic data, develop surface models and assess geomorphic change resulting from river restoration actions. We illustrate the application of the model to a river restoration project in the NW of England, to show how SfM techniques have been used to assess whether the project is achieving its geomorphic objectives. We outline the details of each stage of the workflow, which extend from preliminary decision‐making related to the establishment of a ground control network, through fish‐eye lens camera testing and calibration, to final image analysis for the creation of facies maps, the extraction of point clouds, and the development of digital elevation models (DEMs) and channel roughness maps. The workflow enabled us to confidently identify geomorphic changes occurring in the river channel over time, as well as assess spatial variation in erosion and aggradation. Critical to the assessment of change was the high number of ground control points and the application of a minimum level of detection threshold used to assess uncertainties in the topographic models. We suggest that these two things are especially important for river restoration applications. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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In the central Aegean, the Cycladic island of Amorgos consists of two high‐pressure (HP) units, the marble‐rich Amorgos unit, which is correlated to the Mesozoic ‘cover’ sequence of the Menderes Massif, and the Cycladic Blueschist unit. New structural data show that the deformation history of the Amorgos HP‐rocks was principally governed by early Oligocene (or late Eocene)–early Miocene ductile to brittle thrusting (D1–D3) followed by middle–late Miocene oblique contractional movements (D4–D5). The D1 phase caused syn‐blueschist‐facies ductile thrusting of the Cycladic Blueschist unit over the Amorgos unit, with ambiguous kinematics. Progressive deformation under continuous NW–SE compression produced a sequence of imbricate NW‐directed thrusts (D2/3) characterized by a stratification of fault‐related rocks, with mylonitic zones (D2) giving way downwards to cataclastic zones (D3). Ductile D2 thrusting synchronous to greenschist‐facies retrogression, was accompanied by mega‐sheath folding during constrictional and general shear deformation. Brittle D3 thrusting was associated with NW‐verging F3 folds trending at a high‐angle to the transport direction. Orthogonal contraction gave way to transpression during which the compression orientation changed from NW–SE (D4) to NE–SW (D5). Back‐arc related NW–SE pure extension (D6) seems to have been established in post‐late Miocene times and related high‐angle normal faulting affected HP‐rocks only after they had already reached the uppermost crustal levels. Oligocene–early Miocene deformation history is interpreted to indicate syn‐compressional exhumation of HP‐rocks possibly in an extrusion wedge. In this case, Amorgos HP‐rocks should have occupied the base of the extrusion wedge. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
6.
讨论了以地理信息系统作为建模与仿真过程的空间信息支持 ,在高层体系结构 (HLA)提供的RTI服务基础上 ,运用多线程技术实现地理信息系统作为仿真成员的HLA接口的设计与实现。实验表明 ,能够满足仿真的需求  相似文献   
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  总被引:2,自引:0,他引:2  
To retrieve wind field from SAR images, the development for surface wind field retrieval from SAR images based on the improvement of new inversion model is present. Geophysical Model Functions(GMFs) have been widely applied for wind field retrieval from SAR images. Among them CMOD4 has a good performance under low and moderate wind conditions. Although CMOD5 is developed recently with a more fundamental basis, it has ambiguity of wind speed and a shape gradient of normalized radar cross section under low wind speed condition. This study proposes a method of wind field retrieval from SAR image by combining CMOD5 and CMOD4 Five VV-polarisation RADARSAT2 SAR images are implemented for validation and the retrieval results by a combination method(CMOD5 and CMOD4) together with CMOD4 GMF are compared with QuikSCAT wind data. The root-mean-square error(RMSE) of wind speed is 0.75 m s-1 with correlation coefficient 0.84 using the combination method and the RMSE of wind speed is 1.01 m s-1 with correlation coefficient 0.72 using CMOD4 GMF alone for those cases. The proposed method can be applied to SAR image for avoiding the internal defect in CMOD5 under low wind speed condition.  相似文献   
9.
建筑密集区高倾角三维地震勘探效果   总被引:2,自引:1,他引:2  
高倾角地区(地层倾角40~70°)一直是三维地震勘探的难题,特别是在地表建筑物极复杂区(占工区的95%)实施三维地震勘探,显得难度更大。本文从观测系统设计、炮点、检波器的特殊布设及特观设计上,论证了其可行性。对高倾角且建筑物密集区的三维地震勘探进行了探索,并取得了可喜的成果。  相似文献   
10.
1998年夏季ITCZ和副高异常特征的分析   总被引:1,自引:0,他引:1  
运用GMS的红外亮温和常规气象资料,分析了1998年6~8月ITCZ和副高活动的异常特征。结果指出:ITCZ显著偏弱,副高异常强大且位置偏南偏西,并且是造成台风活动异常偏少和长江流域大水的十分重要原因:ITCZ和副高这些特征的形成,与西南季风弱和中纬度地区冷空气频繁南下密切相关  相似文献   
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