Fig. 10

Lag time plot of detrital zircon fission track peak ages versus depositional ages of Siwalik Group sedimentary rocks from Nepal and modern river sediment from Bernet et al. (2006). Peak ages are given with two σ errors. Old static peak refers to fission track age populations ~ 100 Ma and that do not change up-section. Young static peak refers to fission track age populations ~ 20 Ma and that do not change up-section. The young moving peak of fission track ages that appears after 11 Ma maintains a constant lag time of ~ 4 m.y. but constitutes a smaller fraction of the total sediment mass