Flooding and sediment transport in a small alpine drainage basin in Colorado

Research Article| January 01, 1979 Flooding and sediment transport in a small alpine drainage basin in Colorado Arthur I. Mears Arthur I. Mears 1222 East Gothic Avenue, Gunnison, Colorado 81230 Search for other works by this author on: GSW Google Scholar Author and Article Information Arthur I. Mears 1222 East Gothic Avenue, Gunnison, Colorado 81230 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1979) 7 (1): 53–57. https://doi.org/10.1130/0091-7613(1979)7<53:FASTIA>2.0.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Arthur I. Mears; Flooding and sediment transport in a small alpine drainage basin in Colorado. Geology 1979;; 7 (1): 53–57. doi: https://doi.org/10.1130/0091-7613(1979)7<53:FASTIA>2.0.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract A short-duration, high-intensity rainfall on a 0.43-km2 (105-acre) alpine drainage basin in the central Colorado mountains produced a peak discharge, including water and sediment, of 108 to 134 m3/s (3,810 to 4,730 cfs). This exceeds by an order of magnitude the discharge of the 100-yr flood as predicted by the procedures recommended by the U.S. Soil Conservation Service and exceeds by a factor of two the largest discharge ever reported in a basin of similar size. The Manning formula and superelevation calculations were two methods used to compute velocities and discharges. These two methods depend upon independent sets of assumptions, but they produced similar results. Calculations of the fluid-dynamic stresses required to transport boulders in the upper channel also suggest flood depths and velocities within the range of values computed through use of the Manning formula and superelevation calculations.In the lower channel, bed load moved as inertial grain flows. One flow studied in detail transported sediment onto a part of the alluvial fan not reached by deep flood water. The larger clasts were transported to the top and front of the grain flow. This type of sorting supports a theory of grain-flow deformation first suggested by Bagnold. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.