Geomorphic mapping in parts of Kerala state

Abstract

The paper discusses the advantages aerial photographs offer for a quick appraisal of geomorphic surfaces in a terrain of low to moderate relief, high vegetative cover with considerable human activities. The area studied comprises the coastal tracts between Calicut and Ernakulam and the midlands immediately to the east. Two morphological units, namely the costal plain and uplands constitute the terrain between the Western Ghats and the sea. The costal plain from west to east comprise a narrow beach, a younger beach ridge plain, an older beach ridge plain and lateritic surface, generally plateau shaped with gentle to moderate slopes, terraced, dendritically dissected and with insignificant development of pediment. Further eastwards, the areas of high relief consists of hard crystalline rocks laterised at the top. A filled lagoon near Trichur and the flood plains of major rivers which cut through different geomorphic units are significant. Recognition of isolated, discontinuous patches of highly lateritised Tertiary sedimentaries from other lateritic surfaces is often difficult.