Abstract
The Kalpin Uplift, located along the NW edge of the Tarim Basin in China, is a typical place to study the stratigraphy and structural features of the oil-bearing Paleozoic sequences buried underneath the Basin. Vegetation over the Uplift is extremely sparse and the contrast between lithological features of the sedimentary sequences is excellent in satellite images. The fundamental structure of the Uplift is characterized by a series of ENE-WSW to E-W trending folds and thrust faults, which consist of the thin-skinned thrust system, and Paleozoic sedimentary sequences are repeatedly exposed on the terrain surface. Brief interpretation of false color composite imagery gives an impression that lateral change in the lithology is uncommon over the Uplift, but the detailed stratigraphic analysis of geological units using the ratio images of Landsat TM reveals that some sequences show limited distribution and the lithology of a sequence laterally changes. Specific band combination of the ratio image is selected to discriminate individual rock types based on known spectral features of minerals. The ratio images are combined with Landsat TM band 4 to create a new composite image that enhances lithological features without the loss of geomorphologic detail. Geological phenomena revealed by the correlation of the units are found to be concordant with the evolutional history of the whole Kalpin Uplift, showing the usefulness of the approach focusing on the spectral features of rocks and minerals.
