Sandstone at butte fault line, Chuar Valley [Grand Canyon]. Sketch documents field work of Charles D. Walcott in the Chuar Valley of the Grand Canyon [Arizona] c. 1883. Drawing is likely sketched by B. L. Young. RU 007004, Charles D. Walcott Collection, 1851-1940 and undated; Box 32, Folder 8. SIA2012-9661.