A Re‐examination of the Crater near Crestone, Colorado*

Abstract

Abstract The Crestone Crater is an elliptical bowl measuring 355 feet by 246 feet with a mean depth of 23 feet. It lies in unconsolidated sand on the surface of an alluvial fan at the base of the Sangre de Cristo Mountain Range in the San Luis Valley, Colorado (37° 54′ N, 105° 39′ W). Aerial photographs show the crater as a striking feature in its setting on a gently undulating terrain.We examined the site in August 1963 to appraise the possibility that it was formed by meteorite or comet impact. The crater and its vicinity were mapped at two‐foot contour intervals, and two lines of auger‐hole samples, eight feet deep, were collected across the crater.Sand from the rim and floor is similar in grain size and composition to that several miles to the north and south. It is barren of meteoritic debris, nickel‐iron spherules, rock flour, and impact glass.The crater is less than half as deep relative to its diameter as known meteorite explosion craters. Furthermore, topographic profiles indicate that the crater does not form a depression in the land surface. The crater rim is a positive feature enclosing a basin that has a floor approximately level with the surface of the alluvial fan on which it lies.In the absence of any mineralogic or topographic evidence of impact or explosion, we conclude that this landform is not meteoritic or cometary in origin.