Moenave Formation
The earliest-Jurassic red slope-and-cliff base of the Glen Canyon Group in SW Utah — Lake Dixie beds rich in dinosaur tracks, standing in for the Wingate.
Also known as: Moenave
Mesozoic — the age of dinosaurs
The world back then
Earliest Jurassic, about 200 million years ago. Rivers, ponds, and a shallow lake — 'Lake Dixie' — spread across a rainy, near-equatorial plain, the mud printed thick with dinosaur tracks. Green, wet, and warm, dawn of the age of dinosaurs. The animals are everywhere; you would not want to be small out here.
Now it's the red base of the cliffs in southwest Utah, and you drift past with nothing hunting you. Those old ponds were full of teeth; your river just carries you and lets you look. Being the comfortable animal that shows up long after the dangerous part — that's the luckiest slot in all of time.
Recognize it in the field
- Typical color
- reddish-brown to pale reddish-brown
- Weathers as
- Two-part: the lower Dinosaur Canyon Member is a reddish slope-former; the upper Springdale Sandstone Member forms a blocky cliff.
- Grain
- silt and fine sand
Look for
- a reddish slope capped by a sandstone cliff (Dinosaur Canyon under Springdale)
- earliest-Jurassic 'Lake Dixie' river-and-pond beds
- prolific early-Jurassic dinosaur tracksites
- occupies the Wingate position in southwestern Utah
How this rock was made
Streams, ponds, and the shallow 'Lake Dixie' in a rainy near-equatorial setting at the dawn of the Jurassic.
The setting: river, floodplain, pond, and lake (fluvial-lacustrine)
400–570 ft (NPS Zion); Dinosaur Canyon Member 140–375 ft, Springdale Member 75–150 ft.
In the rock record
Part of the Glen Canyon Group.
↑ Younger — rests above
↓ Older — sits beneath
Where to see it
Regions: Colorado Plateau (SW Utah / Vermilion Cliffs)
- Zion National Park (lower Zion Canyon, Kolob)
- St. George / southwestern Utah
- Vermilion Cliffs