Integrated visible and near-infrared, shortwave infrared, and longwave infrared full-range hyperspectral data analysis for geologic mapping

摘要

Airborne visible/infrared imaging spectrometer (AVIRIS) and spatially coincidenthyperspectral thermal emission spectrometer (HyTES) data were used to map geology and alterationfor a site in northern Death Valley, California and Nevada. AVIRIS with 224 bands from 0.4to 2.5 μm were converted to reflectance. HyTES data with 256 bands covering 8 to 12 μm wereconverted to emissivity. Two approaches were investigated for integration of the datasets for fullspectrum analysis. A combined (integrated) bands method utilized 332 spectral bands spanningboth datasets. Spectral endmembers were extracted, and the predominant material at each pixelwas mapped for the full spectral range using partial unmixing. This approach separated a varietyof materials, but it was difficult to directly relate mapping results to surface properties. Thesecond method used visible to near-infrared, shortwave infrared, and longwave infrared dataindependently to determine and map key endmembers in each spectral range. AVIRIS directlymapped a variety of specific minerals, while HyTES separated and mapped several igneous rockphases. Individual mapping results were then combined using geologically directed logical operators.The full-range results illustrate that integrated analysis provides advantages over use of justone spectral range, leading to improved understanding of the distribution of geologic units andalteration.