The McCauley Sinks comprises several dozen small sinkholes restricted to a 3-km-wide depression. The sinks are arranged in a series of gentle arcs or rings. The size of individual sinks varies, but the largest are ~ 100 m in diameter and 50 m deep. The sinks crop out in Permian Kaibab Formation limestones. Collapse here may be the result of Karst formations in the older Permian Schnebly Hill Formation, which contains evaporites, principally halite (rock salt). From Neal and Johnson, 2002.
Slow subsidence at some sinkholes is an ongoing process (Brian Conway, pers. comm, ca. 2015)