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Konstantinos Topouzelis Vassilia Karathanassi Petros Pavlakis Demetrius Rokos 《国际地球制图》2013,28(3):179-191
Radar backscatter values from oil spills are very similar to backscatter values from very calm sea areas and other ocean phenomena. Several studies aiming at oil spill detection have been conducted. Most of these studies rely on the detection of dark areas, which have high Bayesian probability of being oil spills. The drawback of these methods is a complex process, mainly because non-linearly separable datasets are introduced in statistically based decisions. The use of neural networks (NNs) in remote sensing has increased significantly, as NNs can simultaneously handle non-linear data of a multidimensional input space. In this article, we investigate the ability of two commonly used feed-forward NN models: multilayer perceptron (MLP) and radial basis function (RBF) networks, to classify dark formations in oil spills and look-alike phenomena. The appropriate training algorithm, type and architecture of the optimum network are subjects of research. Inputs to the networks are the original synthetic aperture radar image and other images derived from it. MLP networks are recognized as more suitable for oil spill detection. 相似文献
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A map indicating zones related to groundwater on the mountainous terrain of the island of Naxos, Greece, was produced, using statistics, remote sensing and geographic information system (GIS) techniques. Naxos mainly consists of polydeformed and polymetamorphosed crystalline formations where groundwater is restricted to secondary porosity; its movement is erratic and occurs along lithological contacts, solution openings, faults and fractures. As in the most central Aegean islands, water in Naxos is a scarce commodity. Many dry holes have been drilled. It is known that in areas of such geology, linear features may play a significant role in their hydrogeological regime. Various lineaments’ directional properties were calculated and statistically tested against collected spring data using GIS techniques in an attempt to evaluate the hydrogeological significance of remotely sensed lineaments. Based on the results achieved, a map was prepared to contribute to conventional ground surveys in the selection of drilling sites. The reliability of the map was tested with existing borehole data. The results obtained encourage the use of statistical analysis on remotely sensed lineaments for groundwater targeting studies in crystalline mountainous areas. 相似文献
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Structural Analysis for Gold Mineralization Using Remote Sensing and Geochemical Techniques in a GIS Environment: Island of Lesvos,Hellas 总被引：2，自引：0，他引：2
Rokos D. Argialas D. Mavrantza R. St.-Seymour K. Vamvoukakis C. Kouli M. Lamera S. Paraskevas H. Karfakis I. Denes G. 《Natural Resources Research》2000,9(4):277-293
Exploration for epithermal Au has been active lately in the Aegean Sea of the eastern Mediterranean Basin, both in the islands of the Quaternary arc and in those of the back-arc region. The purpose of this study was the structural mapping and analysis for a preliminary investigation of possible epithermal gold mineralization, using remotely sensed data and techniques, structural and field data, and geochemical information, for a specific area on the Island of Lesvos. Therefore, Landsat-TM and SPOT-Pan satellite images and the Digital Elevation Model (DEM) of the study area were processed digitally using spatial filtering techniques for the enhancement and recognition of the geologically significant lineaments, as well as algebraic operations with band ratios and Principal Component Analysis (PCA), for the identification of alteration zones. Statistical rose diagrams and a SCHMIDT projection Stereo Net were generated from the lineament maps and the collected field data (dip and strike measurements of faults, joints, and veins), respectively. The derived lineament map and the band ratio images were manipulated in a GIS environment, in order to study the relation of the tectonic pattern to both the alteration zoning and the geomorphology of the volcanic field of the study area. Target areas of high interest for possible mineralization also were specified using geochemical techniques, such as X-Ray Diffraction (XRD) analysis, trace-element, and fluid-inclusion analysis. Finally, preliminary conclusions were derived about possible mineralization, the type (high or low sulfidation), and the extent of mineralization, by combining the structural information with geochemical information. 相似文献
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