The Spring Canyon sandstones in the Book Cliffs above the town of Helper, Utah. There are several sedimentary cycles visible in the cliffs (perhaps up to seven or eight)

The Book Cliffs are a series of cliffs in western Colorado and eastern Utah, in the western United States.

[edit] Description and history

Stretching nearly 200 miles from east to west, the Book Cliffs begins where the Colorado River descends south through De Beque Canyon into the Grand Valley (near Palisade, Colorado) to Price Canyon (near Helper, Utah). The cliffs are largely composed of sedimentary materials. The name comes from the cliffs of Cretaceous sandstone that cap many south-facing buttes that appear similar to a shelf of books. The Book Cliffs are within the Colorado Plateau geologic province.

In the Colorado stretch of the Book Cliffs, abandoned coal mines are present, as significant coal resources were present in the region. These mines are now generally capped for safety, but several fatalities of recreational hikers have occurred at these mines since 1989 (due to lack of oxygen/CO₂ gas inhalation).^[1]

In some places, wild horses can be found in the Book Cliffs, for example (in 2008), a band of four was spotted near the abandoned Gearhart coal mine in Mesa County, Colorado.

[edit] Stratigraphy

Book Cliffs and Mt. Garfield (on right, approximate altitude 6,600') in Mesa County, Colorado

The Book Cliffs are one of the world's best places to study sequence stratigraphy. In the 1980s, Exxon scientists used the Cretaceous strata of the Book Cliffs to develop the science of sequence stratigraphy. The Book Cliffs have preserved excellent strata of the foreland basin of the ancient Western Interior Seaway that stretched north south from the Gulf of Mexico to the Yukon in the Cretaceous time. Components of deltaic and shallow marine reservoirs are very well preserved in the Book Cliffs. Earth scientists from the world over visit the Book Cliffs to view analogues of what they are exploring for in the subsurface.

[edit] References

[edit] External links

• Cretaceous Paleogeography - Showing Western Interior Seaway
• The Soils of Western Colorado Mesa, Delta and Montrose Counties