Remote sensing data in lithium (Li) exploration: A new approach for the detection of Li-bearing pegmatites     

《International Journal of Applied Earth Observation and Geoinformation》2019

Remote sensing has proved to be a powerful resource in geology capable of delineating target exploration areas for several deposit types. Only recently, these methodologies have been used for the detection of lithium (Li)-bearing pegmatites. This happened because of the growing importance and demand of Li for the construction of Li-ion batteries for electric cars. The objective of this study was to develop innovative and effective remote sensing methodologies capable of identifying Li-pegmatites through alteration mapping and through the direct identification of Li-bearing minerals. For that, cloud free Landsat-5, Landsat-8, Sentinel-2 and ASTER images with low vegetation coverage were used. The image processing methods included: RGB (red, green, blue) combinations, band ratios and selective principal component analysis (PCA). The study area of this work is the Fregeneda (Salamanca, Spain)-Almendra (Vila Nova de Foz Côa, Portugal) region, where different known types of Li-pegmatites have been mapped. This study proposes new RGB combinations, band ratios and subsets for selective PCA capable of differentiating the spectral signatures of the Li-bearing pegmatites from the spectral signatures of the host rocks. The potential and limitations of the methodologies proposed are discussed, but overall there is a great potential for the identification of Li-bearing pegmatites using remote sensing. The results obtained could be improved using sensors with a better spatial and spectral resolution.  相似文献   

利用经验线方法校准ASTER和ETM+影像——以也门Hajjah东北部为例(英文)     

ALI M. Qaid  BASAVARAJAPPA H T  RAJENDRAN S  ASHFAQ S A 《地球空间信息科学学报》2009,(3)

This study is aimed at using the Empirical Line Method (ELM) to eliminate atmospheric effects with respect to visible and near infrared bands of advanced spaceborne thermal emission and reflection radiometer (ASTER) and enhanced thematic mapper plus (ETM+) data. Two targets (Amran limestone as light target and quartz-biotite-sericite-graphite schists as dark target), which were widely exposed and easy to identify in the imagery were selected. The accuracy of the atmos-pheric correction method was evaluated ...  相似文献   

Application of ASTER and Landsat TM Data for Geological Mapping of Esfandagheh Ophiolite Complex,Southern Iran     

Mohsen Pournamdari  Mazlan Hashim  Amin Beiranvand Pour 《Resource Geology》2014,64(3):233-246

This research developed an approach to enable the discrimination of lithological units and detection of host rock of chromitite bodies within ophiolitic complexes using the advanced spaceborne thermal emission and reflection radiometer (ASTER) and Landsat thematic mapper (TM) satellite data. Three main ophiolite complexes located in southern Iran were selected for the study. A specialized band ratio (4/1, 4/5, 4/7) of ASTER, minimum noise fraction (MNF) components and spectral angle mapper (SAM) on ASTER and Landsat TM data were used to distinguish ophiolitic rock units. Results show that the specialized band ratio was able to identify different rock units and serpentinized dunite as host rock of chromitites within ophiolitic complexes. Minimum noise fraction components of ASTER and Landsat TM data are suitable for distinguishing ophiolitic rock complexes at a regional scale. The integration of SAM and feature level fusion used in this investigation discriminated the ophiolitic rock units and provided geological map for the study area, including identification of high potential areas (serpentinite dunite) for chromite exploration targets.  相似文献   

基于ASTER VNIR-SWIR多光谱遥感数据识别与提取干旱地区岩性信息——以西南天山柯坪隆起东部为例     

时丕龙  付碧宏  二宫芳树 《地质科学》2010,45(1)

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2.35μm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/band1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1.65μm(band 4)具有较高的反射率,而蓝片/绿片岩在2.21μm(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/band6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。  相似文献   

运用LANDSAT ETM+和ASTER数据进行岩性分类   总被引：5，自引：0，他引：5  

余海阔  李培军 《岩石学报》2010,26(1):345-351

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   

基于ASTER数据的遥感蚀变信息提取——以西天山穆龙套地区为例     

茹菲娜·阿力木江  陈川  高玲玲  李顺达 《地球学报》2022,43(2):235-245

西天山是"丝绸之路经济带"和"亚洲金腰带"的核心区和重要组成部分, 世界级的穆龙套金矿床是西天山成矿带内最重要的金矿床之一.作者将前人成果与自身研究结果结合, 形成该篇以穆龙套地区为例的基于ASTER数据的遥感蚀变信息提取的论文.含碳质细碎屑岩是穆龙套地区的溶矿岩层, 矿体受韧性-韧脆性断裂系统的严格控制.穆龙套地区热...  相似文献   

Ice elevation and areal changes of glaciers from the Northern Patagonia Icefield, Chile   总被引：4，自引：3，他引：1  

Andrs Rivera  Toby Benham  Gino Casassa  Jonathan Bamber  Julian A. Dowdeswell 《Global and Planetary Change》2007,59(1-4):126

High thinning rates (up to − 4.0 ± 0.97 m a^− 1) have been measured at Campo de Hielo Patagónico Norte (CHN) or Northern Patagonia Icefield, Chile between 1975 and 2001. Results have been obtained by comparing a Digital Elevation Model (DEM) derived from regular cartography compiled by Instituto Geográfico Militar of Chile (IGM) based upon 1974/1975 aerial photographs and a DEM generated from Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) satellite images acquired in September 2001. A complete cloud-free Landsat ETM+ satellite image mosaic acquired in March 2001 was used to update the available glacier inventory of the CHN, including all glaciers larger than 0.5 km² (48 new glaciers). A new delineation of ice divides was also performed over the accumulation areas of glaciers sharing the high plateau where the existing regular cartography exhibits poor coverage of topographic information. This updated glacier inventory produced a total ice area for 2001 of 3953 km², which represents a decrease of 3.4 ± 1.5% (140 ± 61 km² of ice) with respect to the total ice area of the CHN in 1979 calculated from a Landsat MSS satellite image. Almost 62% of the total area change between 1979 and 2001 took place in glaciers located at the western margin of the CHN, where the maximum area loss was experienced by Glaciar San Quintín with 33 km². At the southern margin, Glaciar Steffen underwent the largest ice-area loss (12 km² or 2.6% of the 1979 area), whilst at the eastern margin the greatest area loss took place in Glaciares Nef (7.9 km², 5.7% of the 1979 area) and Colonia (9.1 km², 2.7% of the 1979 area). At the northern margin of the CHN the lower debris-covered ablation area of Glaciar Grosse collapsed into a new freshwater lake formed during the late 1990s. The areal changes measured at the CHN are much larger than previously estimated due to the inclusion of changes experienced in the accumulation areas. The CHN as a whole is contributing melt water to global sea level rise at rates  25% higher than previous estimates.  相似文献   

基于ASTER遥感数据的西藏多龙矿集区   总被引：2，自引：0，他引：2  

代晶晶  曲晓明  辛洪波 《地质通报》2010,29(5):752-759

矿化蚀变信息的提取对圈定成矿区具有重要意义。近年来,运用多光谱遥感数据进行示矿信息提取得到了长足的发展。常用的示矿信息提取技术方法包括优化的主成分分析方法、比值算法、光谱角算法等。选取西藏改则县多龙地区为研究区,以区内多不杂斑岩型铜矿为典型的已知矿床,基于ASTER遥感数据,运用多种示矿信息提取方法进行靶区圈定综合研究,多种技术方法相互印证,避免了单一算法的局限性,为成矿靶区的圈定提供了更为准确的遥感依据。  相似文献   

基于遥感的河南卢氏西部地区蚀变信息提取与分析     

王建平 《地球信息科学学报》2007,9(6):111-115

近矿围岩蚀变和构造分析是找矿研究的重要内容,遥感异常信息提取、遥感地质解译,结合野外调查能查明围岩蚀变分布情况和构造特征。本文以河南省卢氏县西部地区的成矿远景区为研究区域,选用ASTER多光谱数据和SPOT5高分辨率数据,利用遥感图像波段比值处理方法及特征主组分分析、光谱角填图分类等分析方法,对该地区重要成矿区段做矿化蚀变信息提取及遥感地质综合分析并提供了新的找矿靶区。  相似文献   

Enhanced Destriping of Satellite Data of Ice Surface in Antarctica     

鄂栋臣  沈强 《极地研究(英文版)》2004,(2)

1　Introduction TheAntarcticcontinentissurroundedbyPacificOcean,theAtlanticOceanandthe IndianOcean,itistheisolatedcontinentfarthestfromthemankind.ItsSpecialgeography andclimateenvironmentmakethemankindverydifficulttobeclosetoit,whichlimits mankind'sinvestigationofitandstudytoagreatextent.Restrictioncausedofthegeograph icalenvironmentandtheclimatecanbebrokentoagreatextentwiththeaidofthemodern remotesensingtechnology,itdemonstratesincomparablesuperioritythatremotesensing technologyisusedin…  相似文献