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1.
若尔盖高原地物遥感分类 总被引：2，自引：0，他引：2
各种物质在遥感数据中都有其特征的波谱吸收峰。因此通过波谱识别就可以大大减少以往遥感分类方法中的漏分及混分现象。为了解决若尔盖高原地物遥感分类问题,首次对本区ETM多光谱融合数据采用了地物波谱角分类法进行地物识别。分类步骤:遥感数据定标→选择训练区样本→MNF变换减维去噪处理→利用纯净像元指数(PPI)进行样本提纯→利用n-D散度法进行样本重组→波谱角分类(SAM).其分类结果表明,类别精度评价总精度为0.806,kappa系数为0.785.其精度均符合1:5万比例尺的土地详查工作的技术要求。 相似文献
2.
Spectral mixture analysis (SMA) is an image-processing technique used for the analysis of airborne hyperspectral remote-sensing data which consist of a large number of spectral bands, typically over 100. In this paper the possibilities are examined of using SMA for the analysis of Landsat Thematic Mapper satellite data with only six bands in the visible to shortwave-infrared wavelength. We use data from a semi-arid area in the Sanmatenga province of Burkina Faso, an area known to experience land-degradation problems. In SMA, we assume that pixels in an image consist of one or more homogeneous (uniform in character) or pure surfaces, the so called end-members. The end-members were derived from the image data on the basis of specific image characteristics. Field data was collected to describe the characteristics of these end-members in terms of land cover, soil and degradation phenomena. The end-members derived from the image analysis, although statistically pure in terms of image spectral characteristics, prove to be mixtures at a field scale. This lack of purity is explained by the nature of semi-arid areas which is more heterogeneous than that of most other areas. The SMA yielded cover percentages for the end-members from which an unsupervised classification was made. Comparison of the classification with the results of SMA shows that the latter provides information on the amount and spatial distribution of land characteristics such as land degradation. 相似文献
3.
基于遥感数据的全球及区域土地覆盖制图--现状、战略和趋势 总被引：21，自引：4，他引：17
土地利用／土地覆盖变化研究是近年来全球变化研究的焦点之一。全球和区域尺度的土地覆盖特征对全球环境状况的评估、模拟未来全球环境的情景有重要的作用。2000年在Internat ionalJournalofRemoteSensing杂志上出版了题为"GlobalandRegionalLandCoverCharacterizat ion from Remotely Sensed Data"的专辑。在此基础上,介绍、总结了国际上利用遥感影像进行全球和区域等大尺度土地覆盖研究的新进展。分别从数据源与制图的时空尺度、制图方法（数据预处理、分类、精度评估）等方面进行了介绍,并对现今的两个全球土地覆盖数据库进行了比较分析。 相似文献
4.
运用LANDSAT ETM+和ASTER数据进行岩性分类 总被引：5，自引：0，他引：5
本文评价了运用ASTER和LANDSAT ETM+数据进行岩性制图的性能。分别利用ASTER数据不同波段区图像及其组合,以及ETM+数据进行岩性分类,并探讨了将ASTER和ETM+数据叠加在一起进行了岩性分类; 利用现有地质图对所有分类结果进行了定量评价。结果表明,ASTER数据不同波段的岩性识别能力不同,并且较ETM+数据能更准确地识别岩性。更重要的是,把ASTER与ETM+数据结合在一起进行岩性分类,可获得比用任一数据单独分类更高的分类精度,表明二者的光谱特征具有一定的互补性。 相似文献
5.
M’hamed El Janati Abderrahmane Soulaimani Hassan Admou Nasrrddine Youbi Ahmid Hafid Kevin Patrick Hefferan 《Arabian Journal of Geosciences》2014,7(6):2407-2422
Satellite remote sensing is shown to provide critical support for geological and structural mapping in semiarid and arid areas. In this work, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data were used to clarify the geological framework of the Precambrian basement of the Iguerda Proterozoic inlier in the Moroccan Central Anti-Atlas. In this study, the interpretation of the processed digital data has been ground truthed with geological field data collected during a reconnaissance-mapping program in the Central Anti-Atlas. The Iguerda inlier offers a deeply eroded Precambrian massif dominated by a Paleoproterozoic basement composed of supracrustal metasedimentary units intruded by various Eburnian granitoids. Impressive mafic dyke swarms mainly of Proterozoic age crosscut this basement. Eburnian basement rocks are unconformably overlain by Lower Ediacaran volcanosedimentary rocks of the Ouarzazate Group and Upper Ediacaran–Lower Cambrian carbonates. The applied ASTER analyses are particularly effective in the lithological differentiation and discrimination of geological units of the Iguerda inlier. The spectral information divergence (SID) classification algorithm coupled with spectral angle mapper and maximum likelihood classification effectively discriminates between metamorphic rocks, granitoid bodies, and carbonate cover. SID classification improves geologic map accuracy with respect to the spatial distribution of plutonic bodies and metamorphic units. In addition, Paleoproterozoic granitoids have been well discriminated into separate distinct suites of porphyritic granites, granodiorites, and peraluminous leucogranite suites. This discrimination was initially identified via remote sensing analysis and later ground truthed in the field. This methodology enhances geological mapping and illustrates the potential of ASTER data to serve as a vital tool in detailed geologic mapping and exploration of well-exposed basement of arid regions, such as the Proterozoic of the Anti-Atlas Mountains of Morocco. 相似文献
6.
探索利用高光谱数据的岩性填图新方法是遥感地质应用领域的重要需求之一。本文运用随机森林方法和EO-1Hyperion高光谱数据,对新疆塔里木西北部柯坪地区的局部区域进行岩性分类,并对相关问题进行分析。分别利用光谱特征以及加入光谱一阶导数特征进行岩性分类,并对不同特征对岩性分类的重要性进行分析,同时与现有的基于光谱角制图方法(SAM)进行比较。结果表明,与SAM方法相比,随机森林方法得到了更高精度的岩性分类结果,是一种有效可行的岩性分类方法。根据特征重要性的排序,蓝绿光波段、短波红外波段以及相应的一阶导数特征对研究区Hyperion数据的沉积岩岩性分类贡献更大。 相似文献
7.
离子吸附型稀土矿是我国宝贵的矿产资源,运用遥感影像分类技术提取稀土开采区可以准确地实现对稀土开采状况的监测,但仅利用光谱信息往往难以保证分类精度。本文以江西寻乌稀土矿区为研究区,以IKONOS影像为数据源,应用面向对象分类方法提取了稀土开采区的遥感信息。针对稀土开采区的分布特点,选择基于边缘的分割算法进行影像分割;结合地形信息、光谱信息及几何信息建立规则集,进行特征提取;最后采用隶属度函数法实现面向对象分类,并与传统的光谱角填图分类进行对比分析。研究结果表明,面向对象分类法提取稀土开采区的总体精度为92.49%,Kappa系数为0.857 6,与传统监督分类方法相比有了很大的提高。 相似文献
8.
《Geoforum》2018
The recent explosive growth of user-generated geographic information has drawn significant attention from GIS scholars and human geographers. Volunteered Geographic Information (VGI) here refers to a key component of such a phenomenon, comprising both a range of practices of geographic information production and dissemination by volunteers as well as new forms of geospatial data produced and curated through various interactive online platforms and mobile devices such as OpenStreetMap (OSM) and Google Maps. VGI constructions have raised questions on spatial knowledge, power, and context. Through a study that examines social constructions of OSM in China, this paper makes two contributions to the existing literature: providing a political economic account of VGI constructions in China and exploring legalities in VGI research. Informed by research in critical GIS, this paper traces political economic transitions in relation to OSM constructions and examines OSM contributors' experiences and how these experiences constitute OSM development and usage. Drawing upon law and society research, this paper investigates how OSM mappers encounter the state's regulatory scheme of online mapping. This legality perspective of spatial data production and usage is a topic rarely explored in VGI studies. With interview data and document analysis, this paper unravels processes of powerful state institutional arrangements to control and invest in VGI simultaneously, entrepreneurs' interest in developing location-based services using VGI data, and experiences from a tech-savvy group in exploring and making VGI. While individual experiences vary, they show efforts of questioning embedded power relations shaping spatial data production in these continuously evolving, contested technoscientific and social landscapes. 相似文献
9.
简要叙述航天技术在测缓、遥感和地理信息系统中的应用现状与潜力，包括利用定位卫星的空间大地测量进行各种精度的定位测量，利用各种传感器的航天遥感进行多时相的对地观测和测图。在此基础上构成全球的、区域的和国家级的各种地理信息系统，以满足资源调查、环境保护、灾害防治和全球变化监测的需要。从四化建设和社会持续发展需要出发，对如何发展航天应用技术提出了建设性建议。测绘、遥感和地理信息系统是一个技术十分密集、服 相似文献
10.
This study examines linear spectral unmixing technique for mapping the surface soil types using field spectroscopy data as the reference spectra. The investigated area is located in North Sinai, Egypt. The study employed data from the Landsat 7 ETM+ satellite sensor with improved spatial and spectral resolution. Mixed remotely sensed image pixels may lead to inaccurate classification results in most conventional image classification algorithms. Spectral unmixing may solve this problem by resolving those into separate components. Four soil type end-members were identified with minimum noise fraction and pixel purity index analyses. The identified soil types are calcareous soils, dry sabkhas, wet sabkhas, and sand dunes. Soil end-member reference spectra were collected in the field using an ASD FieldSpec Pro spectrometer. Constrained sum-to-one and non-negativity linear spectral unmixing model was applied and the soil types map was produced. The results showed that linear spectral unmixing model can be a useful tool for mapping soil types from ETM+ images. 相似文献
11.
航天技术在测绘、遥感和地理信息系统中的应用 总被引：2，自引：0，他引：2
简要叙述航天技术在测绘、遥感和地理信息系统中的应用现状与潜力，包括利用定位卫星的空间大地测量进行各种精度的定位测量，利用各种传感器的航天遥感进行多时相的对地观测和测图。在此基础上构成全球的、区域的和国家级的各种地理信，包系统，以满足资源调查、环境保护、灾害防治和全球变化监测的需要。从四化建设和社会持续发展需要出发，对如何发展航天应用技术提出了建设性建议。测绘、遥感和地理信息系统是一个技术十分密集、服务范围极广的先行性、基础性地理信息产业。由于计算机科学和空间科学的迅猛发展，使得测绘、遥感和地理信息系统在数据获取、信息传输、数据处理、成果显示、表达和应用诸方面更多地依赖电子计算机技术和航天技术，并逐步形成了地理信息科学和地理信息产业。 相似文献
12.
遥感技术广泛应用于地质基础调查、矿产资源勘探、环境评估和地质灾害调查等方面。它已从多光谱发展到高光谱阶段,Landsat- 8是目前最具有代表性和最常用的多光谱数据,ASTER具有高的分辨率和多波段特征,资源一号02D(ZY1- 02D)卫星是我国2019年发射的高光谱业务卫星。为了更好地了解多源遥感数据在岩矿识别中的作用,在新疆东天山卡拉麦里地区进行了相关研究。结果表明：Landsat- 8 OLI的PCA变换结果清晰识别了研究区不同的岩性和地层;使用Landsat- 8 OLI、ASTER和ZY1- 02D高光谱数据,分别采取不同的图像端元提取方法,在进行光谱分析的基础上,利用光谱角填图（SAM）即可得到研究区的主要矿物分类图件。通过野外验证,应用GIS技术进行集成和分析,修正相关图件后,便得到了精准的矿物分类综合图。研究表明：多源遥感数据的集成在岩矿识别方面效果良好、前景巨大。 相似文献
13.
以往的滑坡易发性评价多以全体滑坡为研究对象,忽视了滑坡类型的区别。各评价指标对不同类型滑坡的影响程度不同,也导致指标权重无法精确地反映其对滑坡的影响。为更准确地对滑坡灾害进行空间预测,针对西宁市滑坡特征及发育机理,将全区滑坡分为土质滑坡和岩质滑坡;在野外实际调查的基础上,结合相关性分析,选取坡度、坡向、剖面曲率、平面曲率、工程地质岩组,以及滑坡点距断层、水系、道路的距离远近等8项因素作为滑坡易发性评价指标,并通过滑坡点分布密度和滑坡点相对分布密度,分析各评价指标分别对土质滑坡和岩质滑坡的影响;利用信息量模型,计算各评价指标对两类滑坡的信息量值,利用人工神经网络模型,赋予各评价指标对两类滑坡的权重;最后基于GIS平台利用加权信息量模型对研究区进行易发性评价。通过统计方法和ROC曲线法分别计算滑坡易发性评价成功率,结果表明:评价成功率可达到82.61%和82.30%,与未经滑坡分类的成功率比较,分别提高了10.9%和5.2%;同时,经过滑坡分类后,湟水河两岸地质条件较差的地区转变为滑坡高易发区。 相似文献
14.
Mineral targets are local geological anomalies. In a study area of a number of unit cells, mapping mineral prospectivity can be implemented by identifying anomaly cells from the unit cell population. One-class support vector machine (OCSVM) models can yield useful results in anomaly detection in high-dimensional data or without any assumptions on the distribution of the inlying data. The OCSVM model was applied to mapping gold prospectivity of the Laotudingzi-Xiaosiping district, an area with a complex geological background, in Jilin Province, China. The decision function value of each unit cell belonging to an anomaly was computed on the basis of the trained OCSVM model and used to express gold prospectivity of the cell. The receiver operating characteristic (ROC) curve, area under curve (AUC) and data-processing efficiency were used to compare the performance of the OCSVM model and a restricted Boltzmann machine (RBM) model in mapping gold prospectivity. The results show that the OCSVM model outperforms the RBM model in terms of ROC, AUC and data-processing efficiency. Gold targets were optimally delineated by using the Youden index to maximise the spatial association between the delineated gold targets and known gold deposits. The gold targets delineated by the OCSVM model occupy 11% of the study area and contain 88% of the known gold deposits; and the gold targets delineated by the RBM model occupy 10% of the study area and contain 81% of the known gold deposits. Therefore, the OCSVM model is a feasible mineral prospectivity mapping approach. 相似文献
15.
能源勘查、岩石矿物识别、矿物丰度制图以及成矿远景区圈定是高光谱技术发展和应用的主要方向。CASI/SASI航空高光谱数据可以在同一平台下同时获取覆盖可见光-近红外-短波红外光谱段的光谱信息, 且光谱分辨率和空间分辨率远远优于多光谱及星载高光谱数据, 所以在矿物蚀变信息提取中具有广泛的应用前景。以柳园研究区为研究对象, 对CASI/SASI航空高光谱遥感矿物过程中的关键技术进行了实验研究, 确定出航空高光谱矿物蚀变信息提取流程, 并对研究区蚀变矿物进行识别、填图。通过与研究区地质资料和前人实地勘探资料对比得出, 研究区CASI/SASI航空高光谱遥感蚀变异常结果与现实状况相当吻合。 相似文献
16.
从岩石光谱出发,结合光谱谱带强度特征和光谱波形特征,针对机载热红外高光谱数据（TASI）,在以往算法基础上,提出一种改进的算法--光谱离散能级波形匹配法（SDEM）,并将其运用到岩性分类研究中。SDEM算法能识别岩石光谱间的微小差异,并在充分考虑光谱谱带强度和波形特征的同时,有效减弱数据噪声。与传统的岩性分类方法--高光谱角度制图法（SAM）相比,改进的算法能更精确地区分岩石相似光谱,识别易混淆岩性,对出现“异物同谱”现象的岩石也具有更好的区分能力。将SDEM、SAM方法应用于甘肃柳园地区TASI数据岩性分类研究中,可看出SDEM方法能识别出SAM未识别或识别错误的岩性。通过研究区野外查证,可知SDEM方法所得岩性分类结果更符合岩石实际分布情况。可见光谱离散能级波形匹配法具有较好的岩性分类效果,能更好地区分地物。 相似文献
17.
Prediction of the occurrence of slope instability phenomenal through GIS-based hazard zonation 总被引：1，自引：0，他引：1
C. J. van Westen N. Rengers M. T. J. Terlien R. Soeters 《International Journal of Earth Sciences》1997,86(2):404-414
Slope instability hazard assessment is based on the analysis of the terrain conditions at sites where slope failures occurred in the past. For the analysis of the causative factors the application of geographic information systems (GIS) is an essential tool in the data analysis and subsequent hazard assessment. Three scale levels of hazard mapping are defined. A direct experience-driven mapping at reconnaissance level, a statistical approach to determine the causative factors in a quantitative susceptibility mapping and a methodology at large-scale making using of deterministic models. 相似文献
18.
This study presents classifications of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) imagery based on spectral analysis of alteration minerals associated with gold mineralization in Abo Marawat area which is located in the Central Eastern Desert of Egypt. Spectral analysis of continuum removed reference spectra of alteration minerals alunite, kaolinite, sericite, and calcite from USGS and JPL spectral libraries show shifts in position, shape, and strength most probably related to changes in sample purity and particle size of analyzed samples. Spectral Information Divergence (SID) classification method proved successful for mapping sericite, calcite, and clay minerals. Spectral Angle Mapper (SAM) classification identified only sericite and calcite alteration minerals. The identified alteration zones are coincidence with the field sampling and geological map of the study area. The microscopic examination of samples collected from the quartz veins and hydrothermally altered wall-rocks from near surface and subsurface at Abu Marawat gold mine shows sericitization, argillaceous, and carbonatization alteration zones. Gold occurs as very fine inclusions in pyrite, chalcopyrite, and sphalerite and also found filling the fractures between chalcopyrite grains. This study concludes that ASTER image classifications using reference spectra are a stable and reproducible technique for mapping gold related hydrothermal alteration zones in areas with no dominant vegetation cover. 相似文献
19.
MAPGIS在地质制图中的应用 总被引：9，自引：0，他引：9
MAPGIS是我国自主研究开发的大型基础地理信息系统软件平台,具有机助制图、图形编辑和图形处理等多种功能,是我国地质行业数字化制图的首选工具.本文结合工作实例,介绍了MAPGIS在点参数编辑、线参数编辑等方面的数字制图方法和技巧. 相似文献
20.
应用中国首次月球探测工程所获得的嫦娥一号(Change-I)CCD影像数据、干涉成像光谱数据、数字高程模型(DEM)数据和数据分析处理结果等资料,开展了虹湾—雨海地区区域地质综合研究。通过对月球撞击坑及溅射堆积物分析,以及地层单元划分、构造单元划分、岩石类型划分、年代学和月球演化历史的集成分析,依据月坑的形态特征、充填物的多少和保留的程度等,将月球撞击坑划分出7种类型11个亚类,并将月球撞击坑堆积物系统划分为6种类型9个堆积岩组。根据TiO2的含量、分布及影像特征,将月海、月陆玄武岩划分为高钛玄武岩、中钛玄武岩和低钛玄武岩。应用ArcGIS地理信息系统,试点编制了1∶250万月球典型地区——虹湾幅(LQ-4)地质图,并建立了空间数据库,探索制定了月球数字地质图编制技术规范、流程和方法,为中国下一步应用嫦娥二号数据开展"全月球地质图"编制,以及未来其他天体的区域地质综合研究与地质编图工作奠定了基础。 相似文献