Apatite fission-track analysis of Early Miocene to Quaternary distal Bengal Fan sediments from ODP Leg 116 provides a unique perspective on denudation processes associated with the Tertiary Himalayan orogeny. These sediments yield pooled apatite fission-track ages that are 0- to 10-m.y. older than depositional ages. Mean track lengths range from 13.2 to 14.8 &mgr;m. These young ages and long track lengths indicate that rocks in the upper crust of Bengal Fan source areas cooled rapidly (≥15 ¿C/m.y.), implying denudation rates of several hundreds of meters per million years. These observations support the hypothesis that nearly continuous unroofing of a large source area, similar to the dimensions of the present Himalayan and southern Tibetan Plateau deformation front, and an efficient transport system, similar to the present Himalaya-Ganges-Brahmaputra system, supplied sediment to the Bengal Fan since the Early Miocene. ¿American Geophysical Union 1992