ABSTRACT
252By virtue of its narrow bandwidth and higher spectral resolution, hyperspectral data (Hyperion, AVIRIS) can provide an accurate spectral mapping process for surface characterization of geological lithounits. A detailed spectral classification of lithounits as a function of its mineral phase assemblage (rock assemblage) can be further used for geological interpretation of any tectonic event in any area of interest. The lesser Himalayas (Kumaun) have a series of thrusts and faults among the metasedimentary lithounits of regional metamorphic grade. Identification of these lithounits and their respective mineral assemblage to analyze the grade of the rock undergoing metamorphism, lithomapping, mineral phase identification, and so on. Use of a spectroscopic technique (aerial survey) depends on an accurate spectral mapping method. Spectral angle mapper (SAM), binary encoding (BE), and spectral feature fitting (SFF) are the prevalent methods for spectral classification of endmembers or spectral signatures. But to define the weight and evaluation of different spectral mapping methods, validating the data with field spectroscopy to understand its geological implication is needed. The choice of spectral mapping method will proportionally affect the accuracy of arial imagery mapping. The metamorphic spectral classes thus obtained will provide an insight into the geothermal history of the rock assemblages under study.
