ABSTRACT
Because field investigation is difficult in Nepal and because relatively little surveying has been accomplished, only the outline of the geological structure of the country is understood. There is major disagreement over interpreting the evidence and much mapping remains to be done. Nevertheless it is clear that most aspects of the geology of Nepal can be interpreted by reference to the events leading to the creation of the Himalaya and to their continuing evolution. The Himalaya are indeed among the most active geologically of all major mountain systems, and they are still being built up at about one to four millimetres each year. Nepal lies above the colliding boundaries of the Eurasian and Indo-Australian plates. Energy transferred during the closing of the plate boundaries over the last 70 million years folded, compressed, metamorphosed and then uplifted the sediment derived from the erosion of earlier continents and deposited to a thickness of tens of kilometres on the subsiding floor of the Tethys Ocean.
