This project is aimed at an important facet to the major question about when the Himalaya began to uplift and make a large topographic expressions. In northwestern Himalaya uplift and erosion is Middle Miocene, documented by coarse-grained, obvious syn-tectonic sedimentary facies. However, in central and eastern Himalaya, these coarse sediments are missing. The approach taken by this research is to employ the large Sm-Nd differences between possible source regions for establishing when detritus from each entered the Neogene foreland basin desposits in the Siwalik Group. Results are widely applicable to Himalayan tectonics and to climatic and oceanographic consequences of Himalayan uplift and erosion.
