Cutler Group
The Permian red-bed wedge shed off the ancestral Uncompahgre uplift — a single arkosic mass near its source (Fisher Towers) that fans into the named Canyonlands formations.
Also known as: Cutler
Permian — vast deserts, ending in the worst extinction ever
The world back then
Early Permian, around 285 million years ago. A young mountain range — the ancestral Uncompahgre — is shedding itself into the lowlands, rivers and flash floods dumping coarse red sand and granite chunks in great fans off the highlands. It's raw, gritty, red country: braided streams, dry washes, and rubble baking under a hard sun. A mountain literally coming apart into the basin.
Those torn-down mountains are the red towers of Fisher Towers now, and you drift past them doing exactly nothing. It took a whole range collapsing and 285 million years of patience to build that view; you get it with a permit and a hat. The struggle's real — but the range did the hard part, not you.
Recognize it in the field
- Typical color
- red to red-brown (undivided arkose); pale where the White Rim / Cedar Mesa dominate
- Weathers as
- The undivided arkose forms the steep, dark-red fluted cliffs and towers of Fisher Towers and Professor Valley; the divided formations weather as cliffs, slopes, spires, and benches (see members).
- Grain
- fine to coarse, poorly sorted (undivided arkose); varies by member
Look for
- a Permian clastic wedge shed off the ancestral Uncompahgre highland
- coarse arkose proximal (NE, near source) fining basinward (SW)
- fans from undivided formation into named Canyonlands formations
- steep fluted red towers where undivided (Fisher Towers)
How this rock was made
A clastic wedge eroded off the ancestral Uncompahgre uplift (Ancestral Rocky Mountains), coarse and proximal near the source and differentiating basinward into the Paradox-basin formations.
The setting: river-fan (alluvial fan) / braided-river (fluvial) red beds grading to wind-blown (eolian) and marine-margin rock types (facies) basinward
Canyonlands park total up to ~2,500 ft (NPS); undivided Cutler regionally 1,500–8,000 ft (Baars 1962); 0–850 ft as Formation on the Southern Ute Reservation (Condon 1992).
In the rock record
↑ Younger — rests above
↓ Older — sits beneath
Formations in this group
Where to see it
Regions: Colorado Plateau (Paradox Basin)
- divided formations throughout Canyonlands (Needles, Maze, Island in the Sky, Cataract Canyon)
- Fisher Towers
- undivided arkose: Fisher Towers, Onion Creek / Professor Valley, Gateway (Colorado)
Float past it: Cataract Canyon · Meander Canyon · Narrow Canyon