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1.
高分辨率遥感技术在厦门海湾生态环境调查中的应用   总被引:5,自引:0,他引:5  
林桂兰  孙飒梅  曾良杰  庄世坚 《台湾海峡》2003,22(2):242-247,T003
对于局部区域研究,高分辨率卫星遥感及其影像的智能化处理技术是获取信息的新手段.本文以IKONOS遥感影像在厦门海湾的应用为例,探讨高分辨率遥感卫星影像应用于海湾生态环境调查与分析的应用技术.通过分析高分辨率影像地物特征,提出高分辨率遥感影像的重要处理技术:采用不同缩放尺度进行分类和利用空间特征及纹理结构进行专题信息提取。  相似文献   
2.
We present a new approach that incorporates two models to estimate the underwater light field from remote sensing of ocean color. The first employs a series of analytical, semi-analytical, and empirical algorithms to retrieve the spectrum of inherent optical properties (IOPs), including the absorption and the backscatter coefficients, from the spectrum of remote sensing reflectance. The second model computes the profile of photosynthetically available radiation E 0,PAR (z) for a vertically homogeneous water column using the information of the retrieved IOPs and the ambient optical environment. This computation is based on an improved look-up table technology that possesses high accuracy, comparable with the full solution of the radiative transfer equation, and meets the computational requirement of remote sensing application. This new approach was validated by in situ measurements and an extensive model-to-model comparison with a wide range of IOPs. We successfully mapped the compensation depth by applying this new approach to process the SeaWiFS imagery. This research suggests that E 0,PAR (z) can be obtained routinely from ocean-color data and may have significant implications for the estimation of global heat and carbon budget.  相似文献   
3.
This paper investigates the characteristics of bending moments, shear forces and stresses at unit connections of very large floating structures (VLFS) under wave loads. The responses of VLFS are calculated by solving multi-body motion equation considering hydroelasticity and connection stiffness. Hydroelastic responses are calculated by the direct method. Higher-order boundary element method (HOBEM) is used for fluid analysis and finite element method (FEM) is introduced for structural analysis. The equation of motion is modified to describe the unit connections by employing spring elements. Bending moments and shear forces at the connections are obtained from the dynamic equilibrium condition for pressures and inertia forces. Two types of VLFS units such as tandem arranged units and side-by-side arranged units are considered in the numerical examples. The influences of connection stiffness, wave frequency and heading angle on responses of VLFS are investigated through the numerical examples. Rigid body analysis along with hydroelastic analysis is also carried out in the numerical analysis and comparison of those two approaches is discussed.  相似文献   
4.
地质符号的计算机图形学定义   总被引:2,自引:2,他引:2  
地质符号一般均有其特定的图形特征和表示意义,用以表达地质制图中所涉及的具体或抽象的地质对象。本文对地质符号(尤其是岩性符号)的有关计算机图形学方法进行了分析和比较,并在对各种地质符号的分析研究基础上提出了一种地质符号(岩性符号)的计算机图形学定义的新的综合性方法—图元组合法及其分区编码方案  相似文献   
5.
白云岩成岩收缩晶间孔、洞、缝与构造网状缝相互沟通可以组成良好的油气储层,但是这种复杂裂缝—孔隙型储层分布随机性强、发育程度和差异性大,储层预测难度大。本文以中国西部酒泉盆地青西油田下白垩统下沟组湖相白云岩裂缝—孔隙型储层为例,提出地球物理综合预测碳酸盐岩裂缝的方法。本文描述了综合地球物理方法预测碳酸盐岩裂缝储层的实施和应用效果。  相似文献   
6.
位于青藏高原东北缘的西宁、贵德盆地的新生代沉积序列较完整的记录了盆地周围物源区构造变形过程。重矿物是碎屑物质的重要组成部分,是最直观、有效揭示源区母岩、构造-沉积过程的重要手段。通过重矿物的系统分析,结合沉积-构造变形,揭示出始新世-上新世末西宁-贵得盆地及其源区经历了几个构造活动阶段:古新世-始新世早期的隆升阶段、始新世中期-渐新世晚期的构造稳定阶段、渐新世末-中新世初的构造隆升阶段、中中新世构造稳定阶段和晚中新世以来的强烈隆升阶段。并结合特征矿物(绿泥石)及古水流分析,推断古近纪西宁-贵德盆地是东昆仑山前一个统一盆地。中新世早期青藏高原的扩张导致了拉脊山开始隆起,使原型盆地解体;约8.5 Ma以来拉脊山强烈隆升,两侧盆地逐渐转变为山间盆地。这为正确理解青藏高原东北缘盆山格局的形成和演化提供了重要依据。  相似文献   
7.
前人针对珠江口盆地前新生代开展过大量研究,但对盆地的原始构造格局仍缺乏统一认识。在高精度三维地震资料的基础上,笔者采用“定性+定量”先存断裂综合识别技术,识别出珠江口盆地惠州凹陷和番禺4洼前新生代基底发育的先存断裂583条。按照断裂是否断穿Tg和断裂倾角大小,将先存断裂分为4类:高角度节理、低角度节理、高角度活化断层和低角度活化断层;按断裂走向划分,将先存断裂分为NW-NWW向和NE-NEE向2组。燕山期晚侏罗—早白垩世,古太平洋板块对华南板块沿NW向正向俯冲,形成NE-NEE向逆冲断裂;燕山期晚白垩世,古太平洋板块对华南板块斜向俯冲产生左旋挤压应力场导致NW-NWW向逆冲断裂形成。这些先存断裂从源头上控制了珠江口盆地的构造格局,为研究盆地后续演化提供了重要支撑。  相似文献   
8.
The Baluti Formation is exposed succession of the Rhaetian age (Upper Triassic). These strata are interpreted herein for the first time to redeposit in a deep marine setting (distally steepened carbonate ramp/medial to distal slope) on the northwestern margin of the Neo-Tethys. The Galley Derash section is apparently continuous with no evidence for either subaerial exposure or submarine erosion. The absence of erosional scours in the study area confirms emplacement of these strata below both fair-weather and storm wave base. Event beds, particularly those resulting from sediment gravity flows, dominate the Rhaetian interval. The Upper Rhaetian strata are primarily assigned to the Galley Derash Valley. It records an upward transition from moderate-scale, olistolith-bearing debris flow deposits (debrite) to medium-/thin-bedded turbidites remobilized as sediment slumps/slides. The succession is dominated by medium- to thin-bedded calcareous turbidites and hemipelagic suspension deposits. Very low fossil assemblages, particularly stromatolite fragments, and planktonic bivalves occur within some intervals in the section. Rapid and relatively continuous sedimentation is attested to by the thickness of the section, the abundance of calcareous turbidites, and the thin nature of the intercalated hemipelagic beds. Low content of badly preserved fossils and evidence of continuous and rapid sedimentation refer to alteration by tectonic disturbances or diagenesis. This makes the Baluti Beds as a supplementary section for the Rhaetian successions in Iraq.  相似文献   
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10.
In this study, soil radon levels have been measured for the first time across the Ganos fault (GF), which is known as the western part of the North Anatolian Fault Zone. LR 115 Type 2 Solid State Nuclear Track Detectors (time integrated) have been applied to determine soil gas radon levels, and the survey was performed in 16 stations along the fault line. The results showed that soil gas radon concentrations and variation of concentration levels are comparable high along the fault line. It is also observed that in the middle of the Ganos Fault, fairly elevated radon levels were detected. These can be related to the activity of the fault lines. It is confirmed that the study area has a very active tectonic structure and is great location for analyzing radon variations.  相似文献   
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