Mineral Mapping at Lonar Crater Using Remote Sensing

Abstract

Remote is the advanced technology used for various applications in mineral mapping, mineral identification, lithological discrimination and structural mapping etc. Lonar crater is a wellknown impact crater in basaltic crust of rocks. With Hyperion satellite imagery, it is possible to analyze the Lonar crater remotely and comment on the mineralogy associated with it. The various geological, geochemical, mineralogical characterization studies has been done on crater-cum-lake till today but the remote sensing is not used prominently indicating some fruitful results. So the present study focuses on the use of hyperspectral images for mineral mapping and identification near and at the Lonar crater. The preprocessing techniques like bad band removal, destriping, radiometric correction and atmospheric corrections were applied. Then noise removal and dimensionality reduction was performed using modified PCA known as minimum noise fraction. Then the classification techniques Spectral Feature Fitting and Spectral Correlation Mapper were applied on the significant endmembers obtained after Pixel Purity Index and n-D Visualizer. The spectral signatures obtained were compared with USGS standard spectral library. The Alunite mineral was successfully mapped and identified with 88%, 89% and 90% at the different wavelengths at the Lonar Crater.

Lithological discrimination using ASTER and Hyperion data in Salem District, Tamil Nadu

“…However, these datasets commonly encounter challenges due to atmospheric effects, which necessitates atmospheric correction for accurate analysis. This correction process is executed using the FLAASH (Fast Line-of-sight Atmospheric Analysis of Hypercubes) module within the ENVI software [21]. Subsequently, the minimum noise fraction (MNF) transformation is employed to assess the intrinsic dimensionality of the image data, diminish noise within the data, and reduce computational demands for subsequent processing stages.…”