Several contrasting models exist for the tectonic development of the Himalayan and Tibetan Plateau. Each of these models predicts different times for the initiation of crustal thickening, differences in the rate or thickening, and different times for attainment of present crustal thickness. However, none of the existing models predicts the inferred denudation event at 25 to 20 Ma. This study will test the models and determine how widespread was the denudation, using structural mapping and 40Ar/39Ar thermochronology along the Gangdese belt, and in the Yadong-Gulu rift. The thermochronology will also be combined with magneto- stratigraphy on existing samples in order to fully test the models. The results will provide a significant contribution to under- standing the tectonics of collisional and crustal thickening processes.
