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.
TypeFormation
UnderliesWatahomigi Formation, basal member of Supai Group
OverliesRedwall Limestone
Thickness0–122 m (0–400 ft)
Lithology
Primarysandstone, conglomerate, limestone, siltstone
Location
Regionsouthwest Colorado Plateau,  Arizona-(northern)
Country United States-(Southwestern United States)
ExtentGrand Canyon
Type section
Named forSurprise Canyon, Grand Canyon National Park
Named byGeorge 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.