- GeoRef, Copyright 2006, American Geological Institute. Reference includes data from Bibliography and Index of North American Geology, U. S. Geological Survey, Reston, VA, United States
Large grooves up to 33 m wide and 4760 m long have been inscribed in soft unconsolidated lake bottom sediments at Great Slave Lake, NWT. The grooves are probably formed by wind-driven ice floe gouging during each spring breakup. Smaller grooves having a boulder at one end were formed by boulders pushed by floating lake ice. Study of the hydraulics of fluid flow upon spheroidal solids indicates that wind is quite incapable of transporting large rocks like those suggested to have formed the grooves on Racetrack Playa, California.