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1.
由于混合像元的影响,野外实测波谱或从遥感影像提取的像元波谱多为混合波谱。针对高光谱遥感应用中混合像元导致的混合波谱问题,提出了一种改进的比值导数混合波谱分解方法。首先,对野外实测的岩石与植被的混合波谱预处理,消除水汽噪声;其次,使用总体平均经验模态分解法(Ensemble Empirical Mode Decomposition,EEMD)进行IMF分解,获取r分量波谱;然后,利用比值导数方法对r分量波谱进行解混;最后,选取岩石面积比为自变量,近红外波谱的特征波段反射率值为因变量,利用回归分析定量反演野外混合波谱中岩石面积比。结果表明:①基于EEMD分解获取r分量波谱消除了环境干扰,反映了混合波谱总体趋势,体现了混合波谱中的主要地物波谱特征;②对EEMD分解获取的r分量波谱进行比值导数处理,抑制植被端元组分的同时,突出岩石组分对于混合光谱的影响;③结合EEMD和比值导数法处理后的特征波谱,提高了岩石—植物混合波谱反演精度。  相似文献   

2.
由于混合像元的影响,野外实测波谱或从遥感影像提取的像元波谱多为混合波谱。针对高光谱遥感应用中混合像元导致的混合波谱问题,提出了一种改进的比值导数混合波谱分解方法。首先,对野外实测的岩石与植被的混合波谱预处理,消除水汽噪声;其次,使用总体平均经验模态分解法(Ensemble Empirical Mode Decomposition,EEMD)进行IMF分解,获取r分量波谱;然后,利用比值导数方法对r分量波谱进行解混;最后,选取岩石面积比为自变量,近红外波谱的特征波段反射率值为因变量,利用回归分析定量反演野外混合波谱中岩石面积比。结果表明:①基于EEMD分解获取r分量波谱消除了环境干扰,反映了混合波谱总体趋势,体现了混合波谱中的主要地物波谱特征;②对EEMD分解获取的r分量波谱进行比值导数处理,抑制植被端元组分的同时,突出岩石组分对于混合光谱的影响;③结合EEMD和比值导数法处理后的特征波谱,提高了岩石—植物混合波谱反演精度。  相似文献   

3.
由于混合像元的影响,野外实测波谱或从遥感影像提取的像元波谱多为混合波谱。针对高光谱遥感应用中混合像元导致的混合波谱问题,提出了一种改进的比值导数混合波谱分解方法。首先,对野外实测的岩石与植被的混合波谱预处理,消除水汽噪声;其次,使用总体平均经验模态分解法(Ensemble Empirical Mode Decomposition,EEMD)进行IMF分解,获取r分量波谱;然后,利用比值导数方法对r分量波谱进行解混;最后,选取岩石面积比为自变量,近红外波谱的特征波段反射率值为因变量,利用回归分析定量反演野外混合波谱中岩石面积比。结果表明:①基于EEMD分解获取r分量波谱消除了环境干扰,反映了混合波谱总体趋势,体现了混合波谱中的主要地物波谱特征;②对EEMD分解获取的r分量波谱进行比值导数处理,抑制植被端元组分的同时,突出岩石组分对于混合光谱的影响;③结合EEMD和比值导数法处理后的特征波谱,提高了岩石—植物混合波谱反演精度。  相似文献   

4.
随着遥感的不断发展,在地物波谱学研究之后,目前正逐渐展开地物频谱学的研究。地物波谱学研究为遥感打下了理论基础,地物频谱学研究将成为遥感深入发展的重要里程碑。一、地物波谱学——遥感的理论基础地物波谱学研究是由地物光谱学研究开始的,当时研究地物波谱反射特性只限于电磁波谱中的可见光和近红外光谱段。虽然地物反射特性在本世纪初就有人研究,但地物光谱反射特性直到1930年才由原苏联中央测绘科学研究所开始大量考察研究。当时研究的目的是解决航空摄影中的感光材料和滤光镜选择以及反差度和曝光量计算等问题。使用的方法是摄影分  相似文献   

5.
月球表面多光谱数据最佳波段选择研究   总被引:1,自引:0,他引:1  
从传统的多光谱遥感数据最佳波段选择理论入手,结合月球表面的特殊环境,针对月球表面主要岩石对不同波段电磁波的反射特性,分析适合月球表面多光谱数据最佳波段选择的一些方法.  相似文献   

6.
为全面增强遥感影像上地物波谱的反射特性能力,实现对无人机目标的无误提取,提出基于图像分割的无人机遥感影像目标提取技术;在类哈尔滤波器结构的支持下,按照区域环境中地物目标的颜色特征,完成低层影像特征的量化处理,实现基于图像分割技术的无人机遥感深度图获取;定义与无人机遥感影像相关的基本名词,通过原始特征选择的方式,判定地物波谱的平均反射特性水平,得到准确的特征元素相关性测度数值,完成无人机遥感影像的目标融合处理;在此基础上,分割多分辨率条件下的影像目标,在定义图像纹理与尺度条件的同时,得到最终的地物提取结果,实现基于图像分割无人机遥感影像目标提取技术的应用;对比实验结果表明,在初始采集相位条件及亚像素条件下,目标地物的波谱宽度均超过7.0μm,遥感影像的反射特性能力大幅提升,满足对无人机目标无误提取的实用需求。  相似文献   

7.
姚国清 《计算机仿真》2001,18(6):33-35,59
由于遥感图象的复杂性,在遥感图像上直接进行岩石矿物识别是比较困难的,成像光谱数据的应用和人工神经网络模拟技术的日益成熟,为利用遥感图像直接进行岩石矿物识别提供了一种非常有效的方法。该文利用简化的二阶B-P神经网络,用标准的矿物波谱曲线作为训练样本,对试验区内的OH-类矿物进行识别试验,取得了很好的效果。试验表明:利用神经网络技术进行成像光谱数据的岩石矿物识别是非常有效的。  相似文献   

8.
沉积岩石信息的热红外多光谱遥感探测及有效性评价   总被引:8,自引:0,他引:8  
在对热红外多光谱(TIMS)遥感的探测机理及其图像专题信息提取方法的综合分析基础上,以不同沉积岩石的化学成分,矿物组成,结构,反射和发射光谱特征的实验室分析温度测试结果为依据,对不同沉积岩石的热红外多光谱遥感成像机制进行了探讨,并对比分析了不同沉积岩石TIMS图像和TM图像的识别效果。  相似文献   

9.
地物波谱数据库研究现状与发展趋势   总被引:24,自引:2,他引:24  
田庆久  宫鹏 《遥感信息》2002,(3):2-6,46
随着定量遥感技术发展与遥感应用的逐步深入,地物波谱数据库愈加显示其在遥感领域中的重要技术支撑作用。本文着重阐述和分析了国内外地物波谱数据库研究现状和发展趋势,并结合我国当前遥感技术的发展和定量化应用需求,论述了我国未来地物波谱库发展必要性、可行性和总体构想。  相似文献   

10.
地物波谱数据库应用方法及遥感应用现状   总被引:1,自引:0,他引:1  
地物波谱数据库在遥感信息提取中具有重要的应用价值,本文归纳和总结了常用的国内外通用型地物波谱数据库与专业型地物波谱数据库的发展现状。在对有关波谱库遥感应用文献进行计量分析的基础上,综述了地物波谱数据库遥感应用的四种主要方法波谱特征分析、光谱匹配识别、混合像元分解以及参数提取建模,阐述了地物波谱数据库在地物分类、目标识别及参数反演中的应用。从当前所处的遥感"大数据"时代背景出发,亦对地物波谱数据库的建设趋势与应用潜力进行了展望。  相似文献   

11.
The objective of this study was to determine the effect of lichen cover on the spectral reflectance characteristics of granitic rocks. Rock samples collected from bedrock exposures and talus slopes were granodiorite, tonalite, granite, and quartz-diorite. The lichens found on these rocks varied in color, i.e., black, dark brown, medium gray, olive-green, yellow-green, green, orange, and orange-red. The visible and near infrared reflectance spectra (400–1100 nm) of the rock and lichen samples show that lichens can affect the rock's spectra. These changes are dependent on the reflectance contrast between the rock surface and the lichen covering.  相似文献   

12.
The visible–near infrared (VNIR) and short wave infrared (SWIR) spectral bands of both the level 1B, radiance at sensor, and level 2, AST_07 surface reflectance data products of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument were evaluated and compared for mapping the alteration zones around porphyry copper deposits and occurrences at the northern Shahr‐e‐Babak, SE Iran. The level 1B data were converted to reflectance using internal average relative reflectance (IARR) method whereas the AST_07 dataset was processed as delivered. The porphyry copper mineralization occurs in Eocene, andesitic and basaltic rocks with zonal alteration patterns that are concentric and almost symmetrically arranged. The spectral signatures of alteration index minerals collected from field samples and the United States Geological Survey (USGS) spectral reference library, were considered in directed principal component analysis (DPCA) and spectral angle mapping (SAM) algorithms. Carrying out the DPCA method on three spectral bands enhanced the alteration haloes in the last principal component (PC) images. Generating RGB colour composite images using these PC images differentiated three alteration zones from the host rocks. The SAM results of the IARR calibrated dataset discriminated the propylitic, argillic and phyllic alteration zones. It is concluded that the higher spectral resolution of ASTER instrument is effective for mineral mapping. However, the method of conversion from radiance to reflectance is critical to the validity of the outputs and that the pseudo‐reflectance method using the IARR process may be more reliable than the standard reflectance product.  相似文献   

13.
Laboratory spectra have been used for studying the characteristics of desert varnish in the context of Landsat TM data in order to establish its influence on the reflectance of gossans and their discrimination. Supported by limited chemical analysis, reflectance values from selected rock samples have been processed using statistical methods, and spectral plots produced and visually interpreted. Spectral analysis shows that paucity and Mn/Fe proportion in desert varnish, lightness or darkness of the rock, its mineral composition, and the wavelength under consideration control the effect of desert varnish on Landsat TM data. In general, overall reflectance of rocks is reduced by up to 70% in the VIS parts and about 20% in the SWIR parts of the electromagnetic spectrum due to desert varnish. For acidic rocks this effect seems to be intense, whereas mafic rocks are less influenced. The latter generally display spectral crossovers partly due to Mn/Fe content. In the VIS region absorption bands turn to featureless spectra due to desert varnish, whereas in the SWIR spectra are generally subdued but preserved. This has apparently little consequence on the discrimination of gossans from other rock types on composites constituted by bands from the VIS, IR and SWIR parts.  相似文献   

14.
Abstract

Minerals and rocks show varying spectral reflectances under different spectral ranges of the electromagnetic spectrum and such spectral responses vary because of colour, texture, crystal structure, specific gravity and other physical and optical properties. Hence in order to optimise the spectral ranges which may be used in the recognition of the minerals and the rocks, spectral reflectance measurements were carried out for 29 minerals under the visible and near-infrared ranges of the electromagnetic spectrum covered by the TM bands 1, 2, 3 and 4, IRS bands 1, 2, 3 and 4 and SPOT bands 1, 2 and 3. The analysis of the data identifies the optimum spectral bands for distinguishing the different minerals and the mineral aggregates/rocks  相似文献   

15.
Laboratory reflectance (0.4-2.5 w m ) spectra of 41 samples of metamorphic rocks from the Precambrian basement of Madagascar were analysed on the basis of absorption band position and shape, and classified on the basis of recurrent associations of absorption bands. Petrographic analyses allowed us to interpret the absorption features in compositional terms. Spectral and petrographic classes coincided when the principal mineralogy was also spectrally dominant (e.g. in carbonate rocks). When the principal mineralogy did not produce diagnostic spectral features (e.g. in siliceous rocks in the visible-short wave infrared region), the classification was based on spectrally dominant secondary phases. The reflectance spectra were measured on both freshly cut and exposed surfaces of the samples. Apart from a few cases of spectral features obliteration due to kaolinization, or overall albedo change related to texture variation, the two sets of spectra did not significantly differ. The responses of airborne MIVIS and AVIRIS hyperspectral sensors were simulated from spectra representative of the spectral classes, showing that significant identification and classification of well exposed metamorphic rocks are potentially possible using remote instruments providing high quality spectra. Although at present there are no plans for a spaceborne instrument of this quality, TM simulations and band composite images showed that a preliminary gross discrimination of the rocks belonging to the different classes was however possible.  相似文献   

16.
Evaluation of an Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) image of the Mountain Pass, California area indicates that several important lithologic groups can be mapped in areas with good exposure by using spectral-matching techniques. The three visible and six near-infrared bands, which have 15-m and 30-m resolution, respectively, were calibrated by using in situ measurements of spectral reflectance. Calcitic rocks were distinguished from dolomitic rocks by using matched-filter processing in which image spectra were used as references for selected spectral categories. Skarn deposits and associated bright coarse marble were mapped in contact metamorphic zones related to intrusion of Mesozoic and Tertiary granodioritic rocks. Fe-muscovite, which is common in these intrusive rocks, was distinguished from Al-muscovite present in granitic gneisses and Mesozoic granite.Quartzose rocks were readily discriminated, and carbonate rocks were mapped as a single broad unit through analysis of the 90-m resolution, five-band surface emissivity data, which is produced as a standard product at the EROS Data Center. Three additional classes resulting from spectral-angle mapper processing ranged from (1) a broad granitic rock class (2) to predominately granodioritic rocks and (3) a more mafic class consisting mainly of mafic gneiss, amphibolite and variable mixtures of carbonate rocks and silicate rocks.  相似文献   

17.
The Reko Diq, Pakistan mineralized study area, approximately 10 km in diameter, is underlain by a central zone of hydrothermally altered rocks associated with Cu-Au mineralization. The surrounding country rocks are a variable mixture of unaltered volcanic rocks, fluvial deposits, and eolian quartz sand. Analysis of 15-band Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data of the study area, aided by laboratory spectral reflectance and spectral emittance measurements of field samples, shows that phyllically altered rocks are laterally extensive, and contain localized areas of argillically altered rocks.In the visible through shortwave-infrared (VNIR + SWIR) phyllically altered rocks are characterized by Al-OH absorption in ASTER band 6 because of molecular vibrations in muscovite, whereas argillically altered rocks have an absorption feature in band 5 resulting from alunite. Propylitically altered rocks form a peripheral zone and are present in scattered exposures within the main altered area. Chlorite and muscovite cause distinctive absorption features at 2.33 and 2.20 μm, respectively, although less intense 2.33 μm absorption is also present in image spectra of country rocks.Important complementary lithologic information was derived by analysis of the spectral emittance data in the 5 thermal-infrared (TIR) bands. Silicified rocks were not distinguished in the 9 VNIR + SWIR bands because of the lack of diagnostic spectral absorption features in quartz in this wavelength region. Quartz-bearing surficial deposits, as well as hydrothermally silicified rocks, were mapped in the TIR bands by using a band 13/band 12 ratio image, which is sensitive to the intensity of the quartz reststrahlen feature. Improved distinction between the quartzose surficial deposits and silicified bedrock was achieved by using matched-filter processing with TIR image spectra for reference.  相似文献   

18.
19.
基于背景多层次分离的遥感矿化蚀变信息提取模型,以地物的波谱特征和遥感技术的物理机制为基础,以"矿化蚀变岩波谱特征分析—视反射率图像计算—"背景"多层次分离—蚀变信息增强—蚀变信息提取"为技术流程,能快速、准确地提取矿化蚀变信息。以新疆焉耆县哈都虎拉山一带为研究区,以最新的Landsat8-OLI多光谱数据为数据源,将该模型用于提取研究区的黄钾铁矾蚀变岩石信息,共提取出80余处黄钾铁矾蚀变岩石出露点,其中有两处黄钾铁矾蚀变岩石集中分布区,为研究区的找矿工作提供了重要线索。  相似文献   

20.
The Sarfartoq carbonatite complex occurs in the southern West Greenland in a transition zone between Archaean gneiss complex to the south and a Proterozoic mobile belt to the north. The Sarfartoq carbonatite complex consists of a core zone composed of dolomite carbonatite and minor søvite (calcite carbonatite) surrounded by a fenite zone and a marginal zone of gneisses frequently altered due to hydrothermal activity. High spatial and spectral resolution imaging spectrometer data recorded by the HyMap imaging system were used to map lithology of the Sarfartoq carbonatite complex. A careful analysis of the spectral reflectance properties of the carbonatite lithology preceded the HyMap data analysis stage. The spectral reflectance measurements showed that the various lithologic units including dolomite carbonatite, søvite, fenite and the marginal alteration zone have distinct spectral reflectance characteristics. The analysis of the HyMap data was based on an unsupervised clustering algorithm, the Self Organizing Maps (SOM), for the mapping of the main lithology and a hierarchical tree for the mapping of sparsely occurring søvite rocks. Spectral mixture analysis was applied to map fractional abundances and compare with the SOM results. The resulting lithological map shows the spatial distribution of dolomite carbonatite, søvite, fenite with abundant carbonatite dykes (representing the outer core of the carbonatite complex), fenite and hematized gneiss (marginal alteration zone). The results compare well with the field data collected for the assessment of the mapping accuracy and due to the spatially contiguous nature of the hyperspectral data could be used to better map the outcropping carbonatite lithology. The spectral reflectance measurements and the mapping results provide information of petrological importance for the carbonatite core zone.  相似文献   

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