Mindat Logo

The San Rafael Swell

Last Updated: 10th May 2011

The San Rafael Swell is a large anticline situated in south central Utah. It is about 80 miles long running north and south and 35 miles wide. The “reef” formation is pronounced on the east side showing the tilt of the rock like jagged teeth shooting out of the ground. It is famous for the scenic hiking paths that go through slot canyons and water worn ravens.



Iron stains the rock in a kaleidoscope of colors including red, reddish tan, yellow, pink, mauve, and dark olive greens.
The rock strata show thick layers of sandstone often with cross-bedding and herringbone structure. Limestone and shale beds are also present. In the distant past the area was a large desert similar to the Sahara with mini-oceans and thriving river systems.

The “Swell” was formed during the Laramide orogeny some 60 million years ago. Pre-Cambrian dikes buried deep broke up and moved upward pushing the sedimentary rock above it into the structure we see today-sort of. Weathering has helped shape the landscape.

Historically, prospecting and mining in the area has produced mostly uranium and copper. Some of the more famous mines include Temple Mountain mines, Table Mountain mines, Lucky Strike mines, and the North Mesa and Calf Mesa mines. Not much is available from this area now in the way of collecting mineral specimens.

Today, rock hounds collect agate and geodes. The geodes can produce beautiful celestine, calcite, hematite, quartz, and barite crystals.

Pic 1

Pic 2


South of the town of Price and at the north eastern edge of the Swell is the Cleveland-Lloyd Dinosaur Quarry. This quarry is home of the largest concentration of Jurassic dinosaur bones known and where we get most of our parts and knowledge of the meat-eating allosaurs.

Another spectacular feature of the swell is Goblin Valley. It is a valley filled with hoodoo mounds that resulted from weathering of Entrada sandstone (180 to 140 mya). Hoodoos are mushroom shaped rock formations to several meters high.


As a side note: NASA set up a research facility at the southern end of the swell because the terrain is believed to resembles that of Mars.
Personal Note: The state and federal government has tried to designate the area a National Monument. This has not happened yet but it most certainly will in the near future. This would stop all collecting, prospecting, and mining permanently in the area.




Article has been viewed at least 11199 times.

Comments

In order to leave comments to this article, you must be registered
Mineral and/or Locality  
Search Google  
Copyright © Jolyon Ralph and Ida Chau 1993-2014. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them. Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of thousands of members and supporters. Mindat does not offer minerals for sale. If you would like to add information to improve the quality of our database, then click here to register.
Current server date and time: July 29, 2014 04:41:55
Mineral and Locality Search
Mineral:
and/or Locality:
Options
Fade toolbar when not in focusFix toolbar to bottom of page
Hide Social Media Links
Slideshow frame delay seconds