• Spires of Cedar Mesa sandstone in Chesler Park (Needles District)

    Canyonlands

    National Park Utah

Mancos Shale

photo: Slopes of mancos shale
Slopes of mancos shale
 

This layer does not occur in Canyonlands.

Deposited
Mid-Cretaceous (64 to 144 million years ago)

Depositional Environment
Near-shore regimes (e.g. tidal flats)

Appearance
Slope forming, gray shales.

Example
Slopes below the Book Cliffs along I-70 between Grand Junction, CO and Green River, UT. Floor of Cache Valley in Arches National Park.

Did You Know?

Summer Monsoon

Much of canyon country's annual precipitation falls during summer monsoons. These dramatic storms often last less than twenty minutes but can cause powerful flash floods despite their brevity.