Desert greening desiccating winds and the invasion of sand. The Rajasthan Canal system in India is the major irrigation scheme of the Thar Desert and is intended to reclaim it and to check spreading of the desert to fertile areas. Prevention of shifting sand dunes is accomplished through plantations of "Acacia tortilis" near Laxmangarh town. There are few local tree species suitable for planting in the desert region and these are slow growing. The introduction of exotic tree species in the desert for plantation has become necessary. Many species of Eucalyptus, Acacia, Cassia and other genera from Israel, Australia, US, Russia, Zimbabwe,
Thar coalfield metres and rests upon a structural platform in the eastern part of the desert. The generalised stratigraphic sequence in the Thar coalfield area is shown in table. It comprises Basement Complex, coal bearing Bara Formation, alluvial deposits and dune sand. The coal beds of variable thickness ranging from 0.20–22.81 metres are developed. The maximum number of coal seams found in some of the drill holes is 20. The cumulative thickness of the coal beds range from 0.2 to 36 metres. Claystone invariably forms the roof and the floor rock of the coal beds. The coal is brownish black, black and