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1.
传统的单机判读服务系统,存在着判读标准不一、功能单一、插件依赖性高、系统集成性差等问题。在全面分析各类地理空间目标要素构成、地图表示方法和系统功能特点的基础上,对典型判读特征进行了归纳,完成了目标的分类、特征数据库的建立、平台总体架构的设计。基于HTML5和Web GL技术,构建了网络环境下多源、多尺度、多分辨率地理空间目标的三维判读一体化服务平台,实现了面向地理空间目标的判读、检索、三维显示及测试评定于一体的实用判读训练系统,为地理空间目标的网络判读提供了一定参考和借鉴。  相似文献   

2.
梁传坤 《海洋地质前沿》2005,21(11):28-29,37
这是一个地震勘探实例。针对黄土塬复杂地形区、逆冲推覆构造带的复杂性,在冲沟区弯线数据采集方法、非纵测线数据采集技术方面,资料处理中的二维滤波、自动剩余静校正、静校基准面的选取等环节,以及地震资料的综合解释、重一震联合反演技术上,都获得了明显进展。这对中国复杂区的高分辨率地震勘探工作,具有一定的参考价值。  相似文献   

3.
Detailed structural interpretation of the recently acquired deep seismic multichannel profiles along the Iberian Atlantic Margins (IAM Project) provides new results on the geodynamic evolution of the eastern part of the Azores-Gibraltar plate boundary. Thrusting and folding of the oceanic basement and of Mesozoic and Cenozoic sedimentary cover of the Gorringe Bank region are consistent with the N–S convergence of Iberia and Africa. Compressive structures in the Gorringe Bank region are spread over a wide area. Deformation under compression took place mainly in Tertiary times, as is evidenced by a basal unconformity and several discontinuities in Tertiary sediments, although some deformation has also been recorded in Quaternary sediments. The compressive structures in the Gulf of Cadiz are E–W oriented thrusts, folds and related diapiric structures. N–S oriented transpressive deformation is likely to occur in the western Portuguese platform. There is no continuity of structures from the oceanic to the continental domain, suggesting that deformation transfers from one side to the other through a transcurrent fault zone. The fault contact between the two domains is located in the ocean-continent transition zone.  相似文献   

4.
针对不同时相遥感影像中特定目标的变化,研究了基于特征提取的目标变化检测方法。该方法首先根据目标的几何特征进行检测与提取,然后对提取出的两目标影像进行比较,得到特定目标的变化。实验结果表明该方法对特定目标的变化检测有较好的效果。  相似文献   

5.
X-ray images of sediment core allow recognition of fine-scaled sedimentary structures which traditional epoxy casts or lacquer peels are unable to resolve. The X-ray imaging system SCOPIX has the additional advantage of acquiring high-resolution digital pictures suitable for further analysis by advanced image processing techniques. Because of the frequent presence of both physical and biogenic sedimentary structures in undisturbed sediment cores, two image analysis procedures have been established which simplify the information contained in the images (in term of structures and facies), and allow a quantitative characterization of the observed structures. This form of parametrization of the image structure constitutes an additional source of information for a better interpretation of the physical processes responsible for the generation of the sedimentary structures.  相似文献   

6.
在工程设计中,通常采用模块化方式制造超大型浮式结构物,将巨大的单体结构分割成多个较小模块,后期通过合适的连接器拼装形成。为了明确多模块超大浮体在波浪作用下的水弹性响应,以两个相邻层合浮体(高刚度面板和低密度芯材)为研究对象,建立波浪作用下铰接层合浮体水弹性响应的高阶势流模型。采用匹配特征函数展开法求解流体运动的速度势,探讨了铰接处弹簧刚度对浮体的反射系数、透射系数、挠度、弯矩和剪力的影响规律。研究结果表明:迎浪侧浮体的存在可以有效降低背浪侧浮体的挠度、弯矩和剪力幅值;与垂直弹簧相比,扭转弹簧刚度的增加可以更加有效抑制铰接层合浮体的水弹性响应;当扭转弹簧刚度大于一定值时,继续增大弹簧刚度对浮体的动力响应不产生影响。  相似文献   

7.
The summertime phytoplankton bloom near the Kerguelen Plateau is in marked contrast to the low-chlorophyll conditions typical of the Southern Ocean and is thought to arise from natural iron fertilisation. The mechanisms of iron supply to the euphotic zone in this region are poorly understood, and numerical studies of iron transport have until now omitted fine-scale (sub-mesoscale) dynamics which have been shown to significantly increase vertical transport in other parts of the ocean.We present the first sub-mesoscale-resolving study of the flow and vertical transport in this region. The modelled transport and flow structure agree well with observations. We find that an increase in horizontal resolution from mesoscale-resolving (1/20°) to 1/80° resolves sub-mesoscale filamentary frontal structures in which vertical velocities are dramatically higher and are consistent with available observations. Lagrangian tracking shows that water is advected to the surface from much greater depth in the sub-mesoscale-resolving experiment, and that vertical exchange is far more rapid and frequent. This study of sub-mesoscale vertical velocities sets the foundation for subsequent investigation of iron transport in this environment.  相似文献   

8.
In this paper, residual and regional gravity and magnetic anomalies of Saros Bay are separated using wavelet method. Wavelet is one of the modern, stochastic image approaches processing technique in electronics. The vertical, horizontal and diagonal components of wavelet output are evaluated simultaneously and an underground model is obtained by suitable cross-sections. Thus the geological and tectonic properties of Saros Bay are extracted. Our proposed model is confirmed by deep and shallow seismic researches of Turkish Petroleum Cooperation (TPAO). The South-East region of Saros Graben is formed by strike slip Ganos Fault and Anafartalar reverse Fault that lies on the east of Ganos Fault. On the Northwest region, there is strike slip component fault resulting in the Enez Graben. Here we detected two new oval type geological structure, both of them starting from the Eastern direction of Canakkale Dardanelles and but one of them continuing through Gelibolu Peninsuls, while the other tending to the Enez Graben. We think that these structures are the ruins of a very old sea in this region. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

9.
The importance of geomagnetic studies in the World Ocean for deep structure research and fore-casting of mineral resources is noted. A combined method for development of a marine nuclear magnetometer is adduced. The physical background of operation of nuclear magnetometers is analyzed in order to optimize the measurements of the magnetic field. The results of the experiments on detecting nuclear precession signals against the background of ship noises are considered and the elaboration of an MM-1 nuclear magnetometer at the Shirshov Institute of Oceanology is described. A technique for magnetic survey and comprehensive geological interpretation of the anomalies and Z and H field components are presented. Examples of geomagnetic studies performed in the World Ocean with the MM-Inuclear magnetometer are assessed: for the first time in Russia, linear magnetic anomalies were identified and sea-floor spreading rates were calculated (the northern part of the Indian Ocean); a regional geomagnetic survey was carried out in the region of Iceland, which proved the spreading origin of the seafloor in this vast region. A systematic analysis of geomagnetic data obtained with the MM-1 magnetometer in the World Ocean provided the creation and development of the methodology for their tectonic and geodynamical interpretation. On the basis of the geomagnetic data obtained, new fundamental conclusions about the deep structure, kinematics and paleogeodynanics of the World Ocean floor were made.  相似文献   

10.
We present the results of an integrated analogue and numerical modeling study with a focus on structural, stratigraphic and thermal differences between symmetric and asymmetric grabens. These models enable fault interpretation and subsidence analyses in studies of active rifting and graben migration. We imported the surface topography and crustal thinning factors from the analogue models into tectono-stratigraphic forward models which allowed an assessment of the relative importance of sediment stacking in the generation of symmetric and asymmetric grabens. Effects on source-rock maturation zones were calculated through 1D-thermal modeling for different graben types. Combined analogue-numerical modeling appears to be a useful method to simulate natural examples, as shown in this study of the southern Viking Graben in the northern North Sea. This area was formed by Early Permian-Late Jurassic extension, with rifting most intense during the Late Jurassic. The thermal structure of the model, constrained by lithospheric and sedimentary parameters for this region, compares well with actual source-rock maturation data on the southern Viking Graben.  相似文献   

11.
We show the magnetic model of the Selli-Vavilov region. The Selli Line is known as the northwestern edge of the southern Tyrrhenian Basin. The tectonic evolution of the Tyrrhenian Basin is dominated by a Tortonian-Quaternary extension through the eastward movement of the Apennine subduction system. This migration has generated a diffuse stretching of the continental crust with the emplacement of new oceanic material. This latter occurred in several localized zones where the eastward retreating of the Ionian subduction system produced a strong depletion of the crust with formation of basins and correlated spreading. Nowadays the presence of oceanic crust is confirmed through direct drilling investigation but a complete mapping of the oceanic crustal distribution is still lacking. The Selli-Vavilov region shows a differentiated crustal setting where seamount structures, the oceanic basement portions and continental crust blocks are superimposed. To this aim, a 2D inversion of the magnetic data of this region was conducted to define buried structures. The magnetic susceptibility pattern was computed by solving the least squares problem of the misfit between the predicted and real data for separated wavebands. This method produced two 2D models of the high and low frequency fields of the Selli-Vavilov region. The two apparent susceptibility maps provide different information for distinct ranges of depth. The results of the inversions were also combined with seismic data of the Selli region highlighting the position of the highly magnetized buried bodies. The results confirm a role for the Selli Line as a deep crustal boundary dividing the Sardinian passive domain from the easternmost active region where different oceanic structures are located. The Selli Line has worked as a detachment fault system which has moved eastward. Finally, the Selli-Vavilov region may be interpreted as a tectonic result due to a passive asymmetrical rift occurred between the Tortonian and Pliocene.  相似文献   

12.
黄河三角洲刺穿体分布在废弃三角洲叶瓣水下斜坡的下部,成因与密西西比三角洲有很大差别,其形成与软弱层变形(内因)和海洋侵蚀(外因)密切相关。高分辨率黄河三角洲典型的地震地层和解释地层剖面、浅地层剖面和钻孔资料联合解释表明,海底刺穿的发源层来自于河口沙坝下部的前三角洲相软弱层变形。三角洲特有的地层结构造成软弱层上覆的物质压力分布不均,普遍存在一个沿三角洲斜坡下部分布的低压异常带,三角洲堆积过程中,软弱层在低压异常带中的变形已经存在,形成前三角洲上部的凸出地形。黄河口摆动后,海底快速冲刷,在最大冲刷中心也是最大压力释放中心刺穿体形成,随着海洋侵蚀速率减缓,刺穿作用将逐渐减弱,最终将被冲刷消亡。软弱层变形及刺穿对海洋工程设施危害极大。类似这种三角洲特有的地层压力结构在平原海岸地区广泛存在,深入研究软弱层变形机理,对近海工程意义重大。  相似文献   

13.
14.
重力异常平面图的区域划分是地球物理场及地质构造解释的重要参考,但对于大范围数据一直缺少自动化辅助划分方法。基于凝聚层次聚类算法,开展重力异常网格数据的自动化区域划分研究,以空间邻近性为限制条件,分析不同连接方法对模拟重力异常数据的聚类效果,最终选取以Ward法为连接方式的凝聚聚类法,对菲律宾海盆区域的简单布格重力异常数据进行应用实验,并与已有板块划分理论进行对比分析。结果表明:凝聚聚类算法能够根据重力异常数据的空间位置及其数值的大小进行较为合理的自动划分;对菲律宾海盆重力异常的聚类分析结果与已有的板块区划较为接近,能够反映出许多局部细节上的信息,有利于解释工作的开展。因此,聚类分析是研究地球物理场特征的有效辅助工具。  相似文献   

15.
We discuss the possibility of detecting deep convection in the Lofoten Basin of the Norwegian Sea based on the eddy structures revealed from the satellite data. Satellite altimetry, SAR imagery, and MODIS satellite spectral radiometer sea-surface temperature (SST) data are used in the analysis, along with the data of oceanographic Argo floats. It is shown that the eddies identified from the satellite data correspond to the convective cells in the same region according to the data of the Argo floats. We consider several examples of the summer eddy and one winter eddy and the corresponding structures in the ocean measured by the Argo floats when they were located close to the identified eddies. As this method develops and improves, it can be used for the analysis of the dynamic of oceanic eddies in the region of the Lofoten Basin, and possibly in other regions with active deep convection.  相似文献   

16.
《Ocean & Coastal Management》1999,42(10-11):891-908
The paper explores the nebulous concept of heritage in order to highlight issues relevant to the revitalisation and management of historic naval waterfronts. A model separating supply and demand sides, and further subdividing each side into political, social and economic structures, is used as a framework for analysis. The whole is set within a perceptual filter, and interpretation is subsumed within social structure. The model is applied to heritage concepts at Portsmouth Dockyard and to the legacy of naval defence in the neighbouring coastal zone. From the review of all three structures it is shown that economic considerations are increasingly powerful on both the supply and demand sides, as sovereignity passes to customers who are less interested in authenticity and architectural quality than in securing value for money. Issues and implications arising from this trend, and relevant to naval heritage planning and management, are identified.  相似文献   

17.
- Usually, the action of sea ice on offshore engineering structures is one of the controlling loads in cold waters engineering structure design. The reasonable selection of environmental condition and the physical mechanical properties of ice in the region are directly related to the structure design, operation and safety. In this paper, the sea ice force acting on the structure, the physical mechanical properties of ice and the selection of parameters in calculation are discussed. Some suggestions are proposed as to the calculation of various kinds of ice loads acting on the structure.  相似文献   

18.
This study presents the modelling of 2-D and 3-D wide-angle seismic data acquired on the complex, volcanic passive margin of the Vøring Plateau, off Norway. Three wide-angle seismic profiles were shot and recorded simultaneously by 21 Ocean Bottom Seismometers, yielding a comprehensive 3-D data set, in addition to the three in-line profiles. Coincident multi-channel seismic profiles are used to better constrain the modelling, but the Mesozoic and deeper structures are poorly imaged due to the presence of flood basalts and sills. Velocity modelling reveals an unexpectedly large 30 km basement high hidden below the flood basalt. When interpreted as a 2-D structure, this basement high produces a modelled gravity anomaly in disagreement with the observed gravity. However, both the gravity and the seismic data suggest that the structure varies in all three directions. The modelling of the entire 3-D set of travel times leads to a coherent velocity structure that confirms the basement high; it also shows that the abrupt transition to the slower Cretaceous basin coincides in position and orientation with the fault system forming the Rån Ridge. The positive gravity anomaly over the Rån Ridge originates from the focussed and coincident elevation of the high velocity lower crust and pre-Cretaceous basement. Although the Moho is not constrained by the seismic data, the gravity modelled from the 3-D velocity model shows a better fit along the profiles. This study illustrates the interest of a 3-D acquisition of wide-angle seismic over complex structures and the benefit of the subsequent integrated interpretation of the seismic and gravity data.  相似文献   

19.
胶州湾口海区磁力异常特征及构造解释   总被引:1,自引:0,他引:1  
通过对胶州湾湾口海区磁力异常进行的定性和定量解释,并结合其它地质地球物理资料的综合分析认为,测区内存在1条NW向断裂、2条WNW向断裂及3条NE向断裂。其中NW向断裂(F3断裂)是1条新发现的断裂,属右旋断裂构造,并被多种中基性岩脉所填充。根据区内断裂构造的组合交切关系推定,F3断裂比沧口断裂活动时代要早,为非全新世活动断层。  相似文献   

20.
In this paper, we demonstrate the effectiveness of steerable filters as a method of delineating the boundaries of subsurface geological structures. Steerable filters, generally used for edge detection on 2-D images, have the properties of band pass filters with certain directions and are applied to many image processing problems. We first tested the method on synthetic data and then applied it to the aeromagnetic data of İskenderun Basin and adjacent areas.İskenderun Basin is located in the Northeastern Mediterranean where African–Arabian and Anatolian plates are actively interacting. The basin fill records a complex tectonic evolution since the Early Miocene, involving ophiolite emplacement, diachronous collision of Eurasian and Arabian plates and subsequent tectonic escape related structures and associated basin formation. Geophysical investigations of the tectonic framework of İskenderun Basin of Turkey provide important insights on the regional tectonics of the Eastern Mediterranean and Middle East. In this study we show geological structures, which are responsible for the magnetic anomalies in İskenderun Basin and enlighten the structural setting of the Northeastern Mediterranean triple junction using steerable filters. We obtained a magnetic anomaly map of the region from the General Directorate of Mineral Research and Exploration as raw data and then evaluated this by steerable filters. We determined the magnetic anomaly boundaries for İskenderun Basin by using various types of steerable filters and correlated these to drilling data and seismic profiles from the Turkish Petroleum Corporation. The result of the steerable filter analysis was a clarified aeromagnetic anomaly map of İskenderun Basin. The tectonic structure of İskenderun Basin is divided into regions by an N–S trending oblique-slip fault defined by the steerable filter outputs. We propose a new tectonic structure model of İskenderun Basin and modify the direction of the East Anatolian Fault Zone. In our model, East Anatolian Fault Zone cross-cuts the basin as a narrow fault zone and continues towards the Cyprus arc.  相似文献   

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