Change detection is the measure of the distinct data framework and thematic change information that can guide to more tangible insights into underlying process involving land cover and land use changes than the information obtained from continuous change. Land use / Land cover analysis of the semi-urban area was carried out using Landsat TM and ETM+ imageries through Remote sensing software for Vellore district in Tamil Nadu, India. This study attempts to explore the changes along the study areas, two sets of Landsat Thematic Mapper (TM) data were used. TM data are useful for this type of study due to its high spatial resolution, spectral resolution and low repetitive acquisition (16 days).This paper discusses the land use/land cover analysis and change detection techniques using temporal multi-spectral data (1991 and 2001) of the LANDSAT TM images, systematically assessed, and checked in field. Initially 18 major classes were observed for both the images. To minimize similar features, relevant classes were reorganized to end up with 8 classes. The overall accuracy for a 1991 image is 78% and for a 2001 image is 80%. The results demonstrate that the study area experienced a rapid, decrease in forest cover, conversion of wetland vegetation to barren / dry farming, rural to urban conversion in town and municipalities resulting in decreasing ground water table in the 10 year period between 1991 and 2001.

Key words: Land use/ Land cover, Remote sensing and Supervised Classification.