Surprise Canyon Formation
| Surprise Canyon Formation | |
|---|---|
| Stratigraphic range: Late Mississippian (Serpukhovian) | |
| Pattie Butte-(Newton Butte), The ridgeline, north sits on Redwall Limestone 'platform'–(2-places, photo-bottom-left, top of red Redwall cliff), and topped by 2nd-platform of Surprise Canyon Formation. | |
| Type | Formation | 
| Underlies | Watahomigi Formation, basal member of Supai Group | 
| Overlies | Redwall Limestone | 
| Thickness | 0–122 m (0–400 ft) | 
| Lithology | |
| Primary | sandstone, conglomerate, limestone, siltstone | 
| Location | |
| Region | southwest Colorado Plateau, Arizona-(northern) | 
| Country | United States-(Southwestern United States) | 
| Extent | Grand Canyon | 
| Type section | |
| Named for | Surprise Canyon, Grand Canyon National Park | 
| Named by | George H. Billingsley and Stanley S. Beus | 
The Surprise Canyon Formation is a geologic formation that consists of clastic and calcareous sedimentary rocks that fill paleovalleys and paleokarst of Late Mississippian (Serpukhovian) age in Grand Canyon. These strata outcrop as isolated, lens-shaped exposures of rocks that fill erosional valleys and locally karsted topography and caves developed in the top of the Redwall Limestone. The Surprise Canyon Formation and associated unconformities represent a significant period of geologic time between the deposition of the Redwall Limestone and the overlying Supai Group.