CAJ | 학술논문

ASTER多光谱遥感数据目前可以用于岩石矿物资源信息的识别和提取.本研究尝试利用ASTER可见光近红外(VNIR)和短波红外(SWIR)的多光谱遥感数据提取干旱地区的岩石与矿物信息.基于新疆天山西南缘柯坪隆起东部不同地层单元岩石的化学组成和矿物成份以及VNIR-SWIR谱域光谱吸收特征的分析,我们采用相关吸收波段深度(RBD)和波段比值(BR)方法对研究区的多光谱遥感数据进行图像处理,有效区分和识别了白云岩、石灰岩、砂岩以及阿克苏群的蓝片岩-绿片岩和砂质片岩.白云岩的CO_3~(2-)吸收谱带中心波长位于2.32μm,与灰岩的CO_3~(2-)吸收谱带中心波长位置2.35 μm相比,具有向短波长方向移动的特点,据此可以利用RBD7、RBD8分别有效的识别白云岩和灰岩;长英质岩石显示Al-OH和Fe~(3+)VNIR-SWIR吸收特征,而基性-超基性岩石显示Fe~(2+)和Fe、Mg-OH特征,利用不同的铁价态和次要矿物可以区分它们:ASTER band2/bana1代表了含Fe~(3+)矿物分布信息、ASTER band5/band4代表了含Fe~(2+)矿物分布信息、RBD6可以估计Al-OH矿物的丰度;砂质/泥质片岩含较多的多硅白云母、绿泥石、黑硬绿泥石以及风化后表面覆盖的其它粘土矿物,在2.21μm(band6)存在有特征的吸收谱带,并且在1.65 μm(band 4)具有较高的反射率,而蓝片/绿片岩在2.2μm(band 6)反射率较高,不具有明显特征吸收谱带,同时其在1.65μm(band 4)反射率较低,因此蓝片/绿片岩ASTER band4/band6比值低.应用ASTER band4/bana6波段比值可以有效的区分开砂质/泥质片岩与蓝片岩/绿片岩.
ASTER다광보요감수거목전가이용우암석광물자원신식적식별화제취.본연구상시이용ASTER가견광근홍외(VNIR)화단파홍외(SWIR)적다광보요감수거제취간한지구적암석여광물신식.기우신강천산서남연가평륭기동부불동지층단원암석적화학조성화광물성빈이급VNIR-SWIR보역광보흡수특정적분석,아문채용상관흡수파단심도(RBD)화파단비치(BR)방법대연구구적다광보요감수거진행도상처리,유효구분화식별료백운암、석회암、사암이급아극소군적람편암-록편암화사질편암.백운암적CO_3~(2-)흡수보대중심파장위우2.32μm,여회암적CO_3~(2-)흡수보대중심파장위치2.35 μm상비,구유향단파장방향이동적특점,거차가이이용RBD7、RBD8분별유효적식별백운암화회암;장영질암석현시Al-OH화Fe~(3+)VNIR-SWIR흡수특정,이기성-초기성암석현시Fe~(2+)화Fe、Mg-OH특정,이용불동적철개태화차요광물가이구분타문:ASTER band2/bana1대표료함Fe~(3+)광물분포신식、ASTER band5/band4대표료함Fe~(2+)광물분포신식、RBD6가이고계Al-OH광물적봉도;사질/니질편암함교다적다규백운모、록니석、흑경록니석이급풍화후표면복개적기타점토광물,재2.21μm(band6)존재유특정적흡수보대,병차재1.65 μm(band 4)구유교고적반사솔,이람편/록편암재2.2μm(band 6)반사솔교고,불구유명현특정흡수보대,동시기재1.65μm(band 4)반사솔교저,인차람편/록편암ASTER band4/band6비치저.응용ASTER band4/bana6파단비치가이유효적구분개사질/니질편암여람편암/록편암.
Advanced Spaceborne Thermal Emission and Reflection Radiometer(ASTER)can provide high quality of multispectral data for detecting lithology.This study attempted to extract lithlogical and mineralogical information in the arid region using the ASTER multispectral data.Based on the analysis of chemical composition,mineral composition and the spectral absorption characteristics of different lithostratigraphic units,the Relative Absorption Band-Depth(RBD)and the bands-ratio method were adopted to process ASTER Visible-Near Infrared(VNIR)and Shortwave-Infrared(SWIR)muhispectral data from the east Kalpin Uplift,southwest Tian Shan.Limestone,dolomite,sandstone,blueschist/greenschist and psammitic schist/pelitic schist,in the study area were well discriminated.The absorption spectrum center wavelength of dolomite is near 2.32μm is shorter than 2.35μm of limestone,and thus RBD7 and RBD8 can be employed effectively to identify dolomite and limestone,respectively.Felsic rocks show Al-OH and Fe~(3+) absorption characteristics in the VNIR-SWIR region,while the mafic-ultramafic rocks show Fe~(2+) and Fe.Mg-OH absorption features,hence the use of different valence state of iron and secondary minerals can distinguish them:ASTER band2/band1 represent Fe~(3+) distribution.ASTER band2/band1 represent the F~(2+) distribution,RBD6 can estimate the Al-OH mineral abundance.Psammitic/pelitic schist containing phengite,chlorite,stilpnomelane,as well as the weathered surface covered by clay minerals,exist characteristic absorption spectrum in the 2.21μm(band 6),and has a high reflectance in 1.65μm(band 4),while the blueschist/greenschist show high reflectance in the 2.21μm(band 6),and it exit low reflectance in 1.65μm(band 4),and blueschist/greenschist appear low ASTER band4/band6 ratio.Therefore,the band ratio of ASTER band 4 and band 6 can effectively distinguish blueschist/greenschist and psammitic/peIitic schist.