Quantitative assessment of remotely sensed global surface models using various land classes produced from Landsat data in Istanbul     

Naci Yastikli  Umut G. Sefercik  Fatih Esirtgen 《中国地理科学(英文版)》2014,24(3):307-316

Digital elevation model(DEM) is the most popular product for three-dimensional(3D) digital representation of bare Earth surface and can be produced by many techniques with different characteristics and ground sampling distances(GSD). Space-borne optical and synthetic aperture radar(SAR) imaging are two of the most preferred and modern techniques for DEM generation. Using them, global DEMs that cover almost entire Earth are produced with low cost and time saving processing. In this study, we aimed to assess the Satellite pour l'observation de la Terre-5(SPOT-5), High Resolution Stereoscopic(HRS), the Advanced Space-borne Thermal Emission and Reflection Radiometer(ASTER), and the Shuttle Radar Topography Mission(SRTM) C-band global DEMs, produced with space-borne optical and SAR imaging. For the assessment, a reference DEM derived from 1∶1000 scaled digital photogrammetric maps was used. The study is performed in 100 km2 study area in Istanbul including various land classes such as open land, forest, built-up land, scrub and rough terrain obtained from Landsat data. The analyses were realized considering three vertical accuracy types as fundamental, supplemental, and consolidated, defined by national digital elevation program(NDEP) of USA. The results showed that, vertical accuracy of SRTM C-band DEM is better than optical models in all three accuracy types despite having the largest grid spacing. The result of SPOT-5 HRS DEM is very close by SRTM and superior in comparison with ASTER models.  相似文献   

基于ASTER数据的遥感蚀变信息提取——以内蒙古万合永火山盆地为例     

江昌禄  ;吴仁贵  ;彭啟辉  ;祝洪涛 《华东地质学院学报》2014,(3):257-263

应用ASTER遥感影像数据对内蒙古万合永火山盆地进行了铁染、羟基蚀变信息提取研究,结果显示已知矿化点、异常点（带）与提取的铁染异常吻合度较低,而与羟基异常匹配很好,面状、线状蚀变多分布于满克头鄂博组环形构造内部、多组断裂交汇部位以及夹持区,主干断裂周围。另外,在（花岗）闪长岩区域也提取到大面积羟基异常。结合研究区地质资料,圈定出四处找矿有利地段,指出了下一步工作重点。  相似文献   

Discrimination of Different Erosion Levels of Porphyry Cu Deposits using ASTER Image Processing in Eastern Iran: a Case Study in the Maherabad, Shadan, and Chah Shaljami Areas     

Mohammad Hassan KARIMPOUR  Nazi MAZHARI  Azadeh Malekzadeh SHAFAROUDI 《《地质学报》英文版》2014,88(4):1195-1213

The Lut block, eastern Iran, is one of the most extensive Cenozoic magmatic rocks, that show suitable targets for porphyry Cu-Au and high-sulfidation epithermal Au related to porphyry Cu-Au mineralization. In this study, Advanced Spaceborne Thermal Emission and Reflection Radiometer （ASTER） was used to identify different erosion levels of three porphyry Cu deposits, including Maherabad, Shadan, and Chah Shaljami, located in the Lut block volcanic-plutonic belt. Alteration minerals, including kaolinite, dickite, alunite, jarosite, epidote, chlorite, montmorillonite, muscovite, biotite, orthoclase, gypsum, and quartz, are selected to map different alteration zones and erosion levels. Distributions of end-members are mapped by using the SAM and MTMF in VNIR and SWIR of ASTER bands and the results are evaluated against the field studies. For some end-members, the results of SAM processing are more reliable compared to the MTMF because the latter looses field spectra. The use of angle threshold in the SAM, and MF-score and infeasibility value in the MTMF or low abundance of some end-members, and finally comparison of output images of spectral processing show good correlation with alteration maps. Differentiation and explanation of various erosion levels of porphyry Cu deposits are done successfully by using the ASTER sensor data.  相似文献   

基于遥感短波红外技术的三维蚀变填图——以低硫化浅成低温热液型矿床斯弄多为例   总被引：2，自引：0，他引：2  

黄一入  郭娜  郑龙  杨宗耀  伏媛 《地球学报》2017,38(5):779-789

斯弄多银(金)-铅-锌矿床是冈底斯南缘林子宗群火山岩中发现的首例低硫化浅成低温热液型矿床,其发现对于完善区域成矿系列,开拓区域找矿方向都具有重要的意义。本文采用遥感技术与短波红外技术相结合的方法,通过三维建模重现了地表-地下的蚀变矿物组合,形成了星-空-地一体化的三维蚀变填图。本文采用多光谱遥感ASTER数据提取了地表围岩蚀变信息,通过遥感波段比值算法的铁染指数(b2+b3)/b1、镁羟基指数(b6+b9)/(b7+b8)、铝羟基指数(b5/b8)+(b6/b9)分别圈定了矿区地表含有Fe~(3+)、Fe~(2+),Al-OH和Mg-OH等基团的蚀变矿物信息;采用短波红外技术提取了岩心中的绢云母、蒙脱石和伊利石等矿物,并确定了地下的蚀变矿物组合。研究表明,(1)地表蚀变中的Al-OH蚀变信息与钻孔中绢云母的分布非常吻合,遥感的Al-OH信息可作为重要的找矿线索;(2)根据地下蚀变矿物的种类分布,能够确定地表铁染蚀变矿物主要表现为大量褐铁矿化(野外特征明显)、少量黄钾铁矾及绢云母;(3)绢云母形成环境的不同导致其二八面体结构发生变化:Al~ⅥAl~Ⅳ?Mg~ⅥSi~Ⅳ和Fe?Mg,是Mg-OH基团与Al-OH信息在地表部分叠合的重要原因;(4)钻孔中伊利石反射光谱特征参数计算表明,伊利石结晶度(SWIR-IC)在钻孔中呈规律性变化,近矿部位SWIR-IC(1.1~1.4)值域较低,说明伊利石形成温度较低,可能是黏土矿物成岩过程中蒙脱石向伊利石的转化递进反应,远矿段SWIR-IC(1.6~2.1)值域较高,说明该矿物较近矿段而言形成温度相对较高,是绢云母伊利石化的具体反映。  相似文献   

Uncertainty of soil erosion modelling using open source high resolution and aggregated DEMs     

Arun Mondal  Deepak Khare  Sananda Kundu  Sandip Mukherjee  Anirban Mukhopadhyay  Surajit Mondal 《地学前缘(英文版)》2017,8(3):425-436

Digital Elevation Model (DEM) is one of the important parameters for soil erosion assessment. Notable uncertainties are observed in this study while using three high resolution open source DEMs. The Revised Universal Soil Loss Equation (RUSLE) model has been applied to analysis the assessment of soil erosion uncertainty using open source DEMs (SRTM, ASTER and CARTOSAT) and their increasing grid space (pixel size) from the actual. The study area is a part of the Narmada river basin in Madhya Pradesh state, which is located in the central part of India and the area covered 20,558 km². The actual resolution of DEMs is 30 m and their increasing grid spaces are taken as 90, 150, 210, 270 and 330 m for this study. Vertical accuracy of DEMs has been assessed using actual heights of the sample points that have been taken considering planimetric survey based map (toposheet). Elevations of DEMs are converted to the same vertical datum from WGS 84 to MSL (Mean Sea Level), before the accuracy assessment and modelling. Results indicate that the accuracy of the SRTM DEM with the RMSE of 13.31, 14.51, and 18.19 m in 30, 150 and 330 m resolution respectively, is better than the ASTER and the CARTOSAT DEMs. When the grid space of the DEMs increases, the accuracy of the elevation and calculated soil erosion decreases. This study presents a potential uncertainty introduced by open source high resolution DEMs in the accuracy of the soil erosion assessment models. The research provides an analysis of errors in selecting DEMs using the original and increased grid space for soil erosion modelling.  相似文献   

基于ASTER的甘肃柳园地区蚀变信息提取与找矿预测          下载免费PDF全文

胡辉  周萍 《中国地质调查》2017,4(5):86-92

热液矿床常伴随一定的矿化蚀变类型,根据一定的矿化蚀变类型可以预测潜在的成矿有利区。甘肃柳园地区地处黑山—咸泉子深大断裂,热液型矿点多、蚀变丰富,且基岩出露好,可以作为提取遥感蚀变信息的良好示范区。使用ASTER遥感数据,利用主成分分析(principle component analysis,PCA)方法进行的铁染、羟基蚀变异常和碳酸盐化识别及基于SiO₂定量反演的硅化蚀变异常提取结果,与实际情况吻合度达88.9%。通过对区内已知矿床成矿作用、区域构造、蚀变信息和岩石分布特征的研究与分析,成功圈定2处成矿有利区,为该地区找矿勘查提供了依据。研究实例验证了基于ASTER数据的PCA蚀变信息提取和SiO₂定量反演的硅化蚀变异常提取方法的可靠性。该方法可推广至同等类型区域的遥感蚀变信息提取。  相似文献   

结合PCA、多尺度分割及SVM的ASTER遥感蚀变信息提取     

唐淑兰  曹建农  王凯 《遥感学报》2021,25(2):653-664

为了利用遥感影像进行更加精确的找矿预测,本文选择新疆东天山尾亚地区ASTER数据进行矿化蚀变信息提取方法研究。为了提高信息提取精度,本文提出了结合主成分分析(PCA)、多尺度分割和支持向量机(SVM)的遥感矿化蚀变信息提取方法。首先,分析ASTER数据的特征,选取各矿化蚀变信息的特征波段,对组合波段进行主成分分析,获得主分量图像;然后,对各主分量图像进行多尺度分割,并获得分割之后的均值图像;接着,提取训练样本,利用SVM对训练样本进行训练,采用试验方法求得最优核参数和松弛变量,构造最优SVM模型;最后,运用最优SVM模型完成矿化蚀变信息的提取。进行主成分分析时,铁染蚀变信息选择Band1、2、3、4组合,Al-OH基团蚀变信息选择Band 1、4、6、7组合,OH和CO32-基团蚀变信息采用Band 1、2、8、9组合。在运行SVM时采用了序列最小优化算法(SMO)进行求解,速度提高了12%。实验结果表明,与波段比值法、主成分分析法及基于光谱角和SVM的方法等3种方法相比,本文方法提取铁染蚀变信息、Al-OH基团蚀变信息及OH和CO32-基团蚀变信息的总体精度可达到87.98%、 90.01%及88.93%,Kappa系数分别为0.8011、0.8134及0.8023,与成矿区带、已知矿点和已有不同地质背景成矿特征相关性较好。  相似文献   

新疆北山地区侵入岩遥感识别方法     

刘泽  张志  陈建平 《江苏地质》2020,44(4):401-406

基于ASTER数据、Landsat 8数据及WorldView-2数据,采用波段组合法、最小噪声分离法、主成分分析法以及波段比值法,结合岩石光谱曲线,综合提取了新疆北山地区侵入岩的岩性特征。对WorldView-2进行主成分分析和最小噪声分离,并将R(PCA2)G(PCA1)B(PCA4)、R(MNF2)G(MNF1)B(PCA1)、OLI数据R(B7)G(B6)B(B5)进行假彩色合成,利用OLI数据中的B5/B2、B2/B1突出花岗岩。这些方法解决了复杂岩性的影像色调差异较小、细节不清晰等问题,降低了岩性划分及解译的难度,使各种岩性界线更加明晰。结合前人的区域地质调查成果,对研究区侵入岩岩性进行了系统解译及分析。多源遥感数据的综合利用,有助于更有效地识别复杂岩性并进行更详细的岩性分类,提高遥感岩性识别的正确率。  相似文献   

福州市植被信息提取及其景观格局空间变化     

陈志强  杨伟  曹蕾 《亚热带资源与环境学报》2006,21(2):95-97

ASTER(高级空间热辐射热反射探测仪)是高光谱遥感影像时代到来的标志,与一般遥感影像相比能为对地观测提供更高质量的信息源.根据福福州市1988年的TM影像和2001年ASTER影像,在NDVI和分形几何理论方法的基础上,求取两个时期植被斑块的分形维数,结果表明植被景观整体分形维数上升,说明植被斑块空间形态趋向复杂化,稳定性降低,其空间格局变化表现出 2种基本规律一是破碎化,孔隙化,主要发生在城区内部,二是空间萎缩,主要表现在城市边缘地区.  相似文献