Comparison of Landsat multispectral scanner and thematic mapper data from Wind River basin, Wyoming

Landsat Multispectral Scanner (MSS) data are limited by MSS spatial resolution (80 m or 262 ft) and bandwidth selection. Landsat 4 Thematic Mapper (TM) data have greatly enhanced spatial resolution (30 m or 98 ft) and TM operates in spectral bands suited to geologic interpretation. To compare the two systems, three images centered over the Wind River basin of Wyoming were obtained. Two were TM images-a false color composite (FCC) and a natural color composite (NCC)-and the third was an MSS image. A systematic analysis of drainage, landforms, geologic structure, gross lithologic characteristics, lineaments, and curvilinears was performed on the three images. Drainage density and landform distinction were greatly enhanced on the TM images. Geologic features such as faults, strike and dip, folds, and lithologic characteristics are often difficult to distinguish on the MSS image but are readily apparent on the TM images. The lineament-curvilinear analysis of the MSS image showed longer but less distinct linear features. In comparison, the TM images allowed interpretation of shorter but more distinct linear elements, providing a more accurate delineation of the actual dimensions of the geologic features which these lineaments are thought to represent. An analysis of the oil production present in the study area showed 75% of the surface productive structures were delineated on the TM images, whereas only the most obvious structures were visible on the MSS image.