Reflectances of ophiolite rocks in the Landsat MSS bands: relevance to lithological mapping by remote sensing

Abstract

Radiometry performed in situ on natural rock surfaces in the Oman ophiolite demonstrates the muting of spectral distinctions between rock types, due to metamorphism, alteration and weathering. Within class variation and between class overlaps can be minimized by intensity normalization. The use of intensity normalized spectral bands enables maximum-likelihood classification to discriminate some lithologies more effectively than by using ordinary MSS bands. However there is a trade-off between reduction of overlapping reflectances between different rock types and loss of albedo information which is diagnostically useful in some cases.