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1.
基于ArcGIS的条带剖面提取方法在地貌分析中的应用 总被引：3，自引：0，他引：3
条带剖面提取方法是利用数理统计原理,获得垂直于剖面线方向上一定缓冲区范围的高程信息,计算最大、最小和平均高程以及地形起伏度,把地形剖面图对线状地形起伏特征的描述转化为对面状地形起伏特征的描述。该文基于ArcGIS 9.3对三峡地区SRTM-DEM数据进行了条带剖面提取方法研究,实现了基于ArcGIS的条带剖面提取技术流程。应用条带剖面对三峡地区地形地貌进行了定量分析,该方法可快速提取条带剖面,能准确获取高程属性的相关统计参数,对地形地貌信息提取和定量分析具有一定价值。 相似文献
2.
青藏高原北缘公格尔山地区地形梯度的剖析 总被引：2，自引：0，他引：2
本文以青藏高原北缘西昆仑山脉的公格尔山地区为试验区域,基于SRTM-DEM数据,采用线状地形剖面和带状地形剖面的研究方法,对试验区从公格尔山顶到塔里木盆地的地形梯度进行了研究,并探讨了地形梯度与隆升过程之间的关系。研究结果表明:(1)线状地形剖面清晰直观,操作简单;带状剖面法能较好地反映区域的地形起伏状况。若将两种方法联合起来共同进行区域地形研究,则会获得更好效果。(2)从塔里木盆地到公格尔山顶,地形抬升共分3个梯度:分别是从海拔高度2 000m左右上升到约4 500m,从约4 500m上升到将近6 000m,从将近6000m上升到约7500m。地形抬升的不同梯度可能对应着公格尔山晚新生代地貌形成过程的不同隆升过程;而每个抬升梯度的拐点,则对应着不同隆升过程形成海拔高度的分界点。 相似文献
3.
Oddvar Longva Heidi A. Olsen David J.W. Piper Leif Rise Terje Thorsnes 《Marine Geology》2008,251(1-2):110-123
The origin of acoustically transparent fan deposits overlying glacial till and ice-proximal sediments on the southern margin of the Norwegian Channel has been studied using high-resolution seismic-reflection profiles and multibeam bathymetry. The first deposits overlying glacigenic sediments are a series of stacked, acoustically transparent submarine fans. The lack of glaciomarine sediments below and between individual fans indicates that deposition was rapid and immediately followed the break up of the Late Weichselian ice cover. The fans are overlain by stratified glaciomarine sediments and Holocene mud. Because of the uniformity of this drape, the upper surface of the fan deposits is mimicked at the present seafloor, and the bathymetric images clearly show the spatial relationship of the fans to bedrock ridges and the presence of braided channel-levee systems on the surface of the youngest fans. The acoustically transparent character of the fan deposits indicates that they comprise silt and clay, and their lobate form and lack of internal stratification indicates that they were deposited by debris flows. The channel-levee morphology indicates deposition from more watery hyperconcentrated fluid flows. The fan sediments were either derived from 1) erosion of Mid Weichselian lake deposits in southern Skagerrak or 2) from Late glacial ice-margin lake deposits, ponded against the Norwegian Channel ice stream, which collapsed catastrophically when the lateral support was removed as the ice disintegrated. Fans composed almost exclusively of fine-grained sediment need not, therefore, rule out an origin in a deglacial setting relatively close to the former margins of glaciers and ice sheets. 相似文献
4.
A bottom longline fishery operated in the EEZ of New Caledonia from 1988 to 1991. Fishing focused on five seamounts with summits at depths ranging from 500 to 750 m. The target species was alfonsino, Beryx splendens. As the soundings available from marine charts were not detailed enough, the fishing masters had to make their own charts in order to set the gear in the right location. A series of 11 scientific cruises devoted to a research program on alfonsino was launched in late 1991. During the first scientific cruises, several days were spent mapping the seabed to improve the existing knowledge of the topography of three seamounts by coupling the EDO echosounder depth measurements to the GPS positions. As this procedure is slow, it is applicable to limited areas or, if a wider grid is used, to large zones to locate major structures such as ridges and seamounts. The emergence of the multibeam echosounder has greatly improved seabed mapping performance. This tool seems to fit the requirement of exploratory deep-bottom fishing particularly well, as it covers large areas while providing details of the bottom. The EM 12 was used to obtain bathymetry and imagery of the SE portion of the EEZ of New Caledonia, covering an approximate area of 70,000 km2 in two weeks. For depths ranging from 500 to 4,500 m, the results were impressive. They confirmed the known major features and provided greater topographical detail, revealing fine unknown structures. They also provided information on the type of substratum, information which might influence the fishing strategy. Finally, they made it possible to obtain an accurate estimate of the exploitable area which in turn led to new stock estimates. 相似文献
5.
海底勘查技术的最新发展 总被引：4，自引：0，他引：4
本文将介绍用于探测海底三维地质特征的海底勘查的最新发展。它主要包括海底地形测绘技术，海底形貌观测技术、海底地层声学探测技术等。 相似文献
6.
Deformation Patterns of an Accretionary Wedge in the Transition Zone from Subduction to Collision Offshore Southwestern Taiwan 总被引：1，自引：0，他引：1
Char-Shine Liu Benoit Deffontaines Chia-Yu Lu Serge Lallemand 《Marine Geophysical Researches》2004,25(1-2):123-137
Swath bathymetry data and seismic reflection profiles have been used to investigate details of the deformation pattern in the area offshore southwestern Taiwan where the Luzon subduction complex encroaches on the passive Chinese continental margin. Distinctive fold-and-thrust structures of the convergent zone and horst-and-graben structures of the passive margin are separated by a deformation front that extends NNW-ward from the eastern edge of the Manila Trench to the foot of the continental slope. This deformation front gradually turns into a NNE–SSW trending direction across the continental slope and the Kaoping Shelf, and connects to the frontal thrusts of the mountain belt on land Taiwan. However, the complex Penghu submarine canyon system blurs the exact location of the deformation front and nature of many morphotectonic features offshore SW Taiwan. We suggest that the deformation front offshore SW Taiwan does not appear as a simple structural line, but is characterized by a series of N–S trending folds and thrusts that terminate sequentially in an en-echelon pattern across the passive Chinese continental slope. A number of NE–SW trending lineaments cut across the fold-and-thrust structures of the frontal accretionary wedge and exhibit prominent dextral displacement indicative of the lateral expulsion of SW Taiwan. One of the prominent lineaments, named the Yung-An lineament, forms the southeastern boundary of the upper part of the Penghu submarine canyon, and has conspicuous influence over the drainage pattern of the canyon 相似文献
7.
L. A. Morgan W. C. Shanks III D. A. Lovalvo S. Y. Johnson W. J. Stephenson K. L. Pierce S. S. Harlan C. A. Finn G. Lee M. Webring B. Schulze J. Dühn R. Sweeney L. Balistrieri 《Journal of Volcanology and Geothermal Research》2003,122(3-4):221-242
‘No portion of the American continent is perhaps so rich in wonders as the Yellow Stone’ (F.V. Hayden, September 2, 1874)Discoveries from multi-beam sonar mapping and seismic reflection surveys of the northern, central, and West Thumb basins of Yellowstone Lake provide new insight into the extent of post-collapse volcanism and active hydrothermal processes occurring in a large lake environment above a large magma chamber. Yellowstone Lake has an irregular bottom covered with dozens of features directly related to hydrothermal, tectonic, volcanic, and sedimentary processes. Detailed bathymetric, seismic reflection, and magnetic evidence reveals that rhyolitic lava flows underlie much of Yellowstone Lake and exert fundamental control on lake bathymetry and localization of hydrothermal activity. Many previously unknown features have been identified and include over 250 hydrothermal vents, several very large (>500 m diameter) hydrothermal explosion craters, many small hydrothermal vent craters (1–200 m diameter), domed lacustrine sediments related to hydrothermal activity, elongate fissures cutting post-glacial sediments, siliceous hydrothermal spire structures, sublacustrine landslide deposits, submerged former shorelines, and a recently active graben. Sampling and observations with a submersible remotely operated vehicle confirm and extend our understanding of the identified features. Faults, fissures, hydrothermally inflated domal structures, hydrothermal explosion craters, and sublacustrine landslides constitute potentially significant geologic hazards. Toxic elements derived from hydrothermal processes also may significantly affect the Yellowstone ecosystem. 相似文献
8.
多波束条带测深仪研究发展动态 总被引：6，自引：0，他引：6
多波束条带测深仪是一种近年发展起来的具有高测量效率、高测量精度、高分辨率的海洋海底地形测量设备,特别适合于大面积的扫海测绘作业。本文较详细地总结了这种水声测量仪器目前在国内、外研究发展的概况,并分析了其未来研究发展的可能方向 相似文献
9.
There is a pressing need for standardization of data derived from bathy‐metric swath‐mapping systems. Currently several dozen multibeam and sidescan sonar data formats exist within the oceanographic community, and more can be expected as new systems are developed. Without some standardization of swath‐mapping data formats, the capability for use and integration of data from different systems will be severely compromised. This paper presents a strategy for organizing swath bathymetry data in a logical modular fashion that will allow data from all current swath bathymetric sonar systems to be stored and accessed in a common fashion. We have chosen the approach of defining compact efficient modules for each logically independent portion of a data record and storing it in a manner that is portable between diverse computer architectures and operating systems. This approach is extensible to accommodate new types of data. Although specifically developed for swath bathymetry, this format is also capable of supporting digital sidescan data and other types of swath data. 相似文献
10.
计算机环境下地貌晕渲图制作的探讨 总被引：1，自引：0，他引：1
本文以1∶100万标准分幅的成都幅(H-48)为例,采用SRTM-DEM数据,利用ERDAS软件、MicroDEM软件和Global Mapper软件,进行地貌晕渲图原图的制作,并利用Photoshop软件,对它们生成的地貌晕渲图原图进行了颜色调整、效果优化和与地图底图叠加生成最终的地貌晕渲图。研究表明:(1)利用3种软件进行地貌晕渲图原图的制作各有优缺点,但就最终成果图的整体质量和效果来看,Global Mapper软件制作的地貌晕渲图要优于MicroDEM软件制作的地貌晕渲图,而以ERDAS软件制作的地貌晕渲图的质量和效果最差;(2)Photoshop软件作为强大的图形图像处理软件,可以在地貌晕渲图的效果调整和质量优化上起到重要作用;(3)由于数字环境下地貌晕渲图可以表达更多的信息量和色彩效果,它对于制图人员色彩的运用、表达效果的判断和调整能力等提出了更高的要求和挑战。 相似文献