A Review of Landsat False Color Composite Images for Lithological Mapping of Pre-Cambrian to Recent Rocks: A Case Study of Pail/Padhrar Area in Punjab Province, Pakistan

Abstract

This research is based to review the efficacy of Landsat thematic mapper (TM) on different band combinations for mapping of different geological formations ranging in age from Pre-Cambrian to most recent rocks. These band combinations include 742, 247, 564, 456, 567 and 765. Out of these, the most suitable false color composite combination is assessed for differentiation of lithology. To differentiate formations, the Landsat TM image is processed in Erdas imagine software and accordingly different lithological formations are identified on the basis of their tonal variations. Findings of the research show that 742 and 247 are the most suitable false color composite for sedimentary rocks of lower eocene (Nammal and Sakaser Formations), middle and lower Miocen (Murree and Kamlial Formations) and Pre-Cambrian (Salt Range Formation) lithological formations. The 564 and 456 FCC combinations have complexities in the identification of different lithologies; however, 456 FCC combination identified Paleocene rocks of Makarwal group (Patala Formation) and Pre-Cambrian (Salt Range Formation). The other two combinations 567 and 765 differentiate only middle Pliocene (Chinji and Nagri Formations), whereas lower eocene (Chorgali Formation) reflects fluctuating tonal behavior. The other lithologies are unidentifiable in these two combinations. Findings of the research are the base for the utilization of Landsat TM data in identification of similar lithologies in the salt range as well as in other areas having sedimentary rocks.