Shapes, Scales and Spacing of Channel-belt Sand Bodies in Ancient and Experimental Avulsion-dominated Alluvial Basins Paul Heller - Dept. of Geology & Geophysics, University of Wyoming, Laramie, WY 82071 Snehalata Huzurbazar - Dept of Statistics, University of Wyoming, Laramie, WY 82071 Chris Paola - Dept. of Geology & Geophysics, University of Minnesota, Minneapolis, MN 55455 This study demonstrates that there is a range of scales of organization of channel sand bodies in at least some alluvial basins. These include: single story sand bodies formed as individual rivers avulse across flood plains multistory sand bodies that form by reoccupation of topographic lows where preexisting channels existed. avulsion clusters that appear to form by local avulsions where the river avulses from spot to spot but within one part of the alluvial basin at the largest scale the distribution of avulsion clusters may be controlled by regional avulsion of the river across the basin.