Neogene volcanic activity was active on the Colorado Plateau. It ranged from the entire perimeter around the plateau, but also Kaibab Plateau at Grand Canyon, San Francisco Peaks (still active, Sunset Crater), and extended southeast to the Mogollon-Datil volcanic field. Besides alluvial deposits, or Quaternary sand dune deposits, the Bidahochi is possibly the sole geologic formation, that is non-volcanic in origin, during the Neogene, on the Colorado Plateau; it is at least one of the largest, non-volcanic in the Neogene on the plateau.