Rocky Mountain (56th Annual) and Cordilleran (100th Annual) Joint Meeting (May 3–5, 2004)

Paper No. 21
Presentation Time: 8:00 AM-5:00 PM

LANDSLIDING AND STREAM POWER IN THE VICINITY OF THE TSANGPO RIVER GORGE AT NAMCHE BARWA, EASTERN TIBET


BUNN, Jeremy T., Earth & Space Sciences, Univ of Washington, Box 351310, 310 Condon Hall, Seattle, WA 98195, FINNEGAN, Noah, Earth & Space Sciences, Univ of Washington, PO Box 351310, Seattle, WA 98195-1310 and MONTGOMERY, David R., Earth and Space Sciences & Quaternary Research Center, Univ of Washington, 63 Johnson Hall, Box 351310 University of Washington, Seattle, WA 98195, turlo@u.washington.edu

Recent work has explored the relationship between localized extremes of uplift and denudation in the eastern and western syntaxes of the Himalaya. We hypothesize that the rapid uplift is largely accommodated by mass wasting from threshold hillslopes, with the rate controlled by river incision. To assess this mechanism, we analyzed unit stream power (derived from DTED level 1 digital elevation data, TRMM precipitation data and Landsat-derived widths) in conjunction with landslides mapped from Landsat images. Our results show coincidence of high stream power and high landslide density in the vicinity of Namche Barwa in the eastern Himalaya. This is consistent with the hypothesis that landsliding on threshold hillslopes controlled by a rapidly down-cutting river has contributed to anomalously high rates of erosion and uplift in the Namche Barwa syntaxis.