Application of GPS and ERS Techniques for the Mapping of Out-crops Vs Soil Cover and its Thickness, in Some Mountainous Part of the Sikkim Himalayas

Sikkim is primarily mountainous topography which is the main part of the Eastern Himalayas. Maximum portion of the northern district is rock exposure covered with snow and ice. Lithologically, a major part of this area is covered by highly crushed and fractured meta-sedimentary rock of Baling series with a patch of high-grade gneissic exposure. Due to deep weathering accompanied by high rainfall, the rock has been transformed into thick soil of sandy and silty in nature. This is highly capable of storing sub-soil water. This paper is attempted to find out with the help of modem techniques like GPS and ERS, the depth of the soil, surface soil covered area and rock exposure in and around the mountainous part of the Sikkim Himalayas.