San Rafael Swell

San Rafael Swell

The San Rafael Swell is a large geologic feature located in south-central Utah, USA about 30 miles (50 km) west of Green River, Utah. The San Rafael Swell, approximately 75 miles by 40 miles (120 x 65 km), consists of a giant dome-shaped anticline of sandstone, shale, and limestone that was pushed up millions of years ago. Since that time, infrequent but powerful flash floods have eroded the sedimentary rocks into numerous valleys, canyons, gorges, mesas and buttes. The Swell is part of the Colorado Plateau physiographic region.


Interstate 70 divides the Swell into northern and southern sections, and provides the only paved road access to the region. The swell lies entirely within Emery County.

The northern Swell is drained by the San Rafael River, while the southern Swell is drained by a number of small creeks which eventually join the Dirty Devil River in Hanksville, Utah. The Dirty Devil River is a tributary of the Colorado River, while the San Rafael River joins the Green River before it also flows into the Colorado. Muddy Creek cuts into the western edge of the Swell, exits at Muddy Creek Gorge, and then flows into the Fremont River.


The San Rafael Swell was formed when deeply buried Precambrian rocks faulted, or broke, during the Laramide orogeny, about 60 million years ago. These "basement" rocks below the present-day Swell moved upwards relative to the surrounding areas and caused the overlying sedimentary rocks to fold into a dome-like shape called an anticline. The resulting structure is analogous to a series of blankets draped over a box.

Since that time, the relentless force of running water has eroded the geologic layers, resulting in older rocks becoming exposed in the middle of the Swell, and younger rocks exposed around the edges. Many of the most impressive landforms are composed of more resistant rocks, including the Jurassic Navajo Sandstone, Triassic Wingate Sandstone, and Permian Coconino Sandstone. The folding is much steeper on the eastern edge of the Swell than in the west, and this eastern edge is referred to as the San Rafael Reef.

Part of swell has geographic features that resembles Mars. The Mars Society decided to set up the Mars Desert Research Station in the area as a Mars analog for such reasons.


Evidence of Native American cultures, including the Fremont, Paiute, and Ute, is common throughout the San Rafael Swell in the form of pictograph and petroglyph panels. From about 1776 to the mid-1850's the Old Spanish Trail trade route passed through (or just north of) the Swell. In the past 150 years, areas of the Swell have been used for the grazing of sheep and cattle, as well as for uranium mining. Although surrounded by the communities of Price, Green River, Hanksville, Ferron, Castle Dale, and Huntington, the Swell itself does not support permanent residents.


The area is managed by the U.S. Bureau of Land Management, although the Swell as a whole does not currently enjoy special protection, parts of it are protected as wilderness study areas. Cattle grazing is only allowed in parts of The Swell that are not designated as such. The San Rafael Swell is also dotted with squares of land managed by The Utah School and Institutional Trust Lands Administration, as is much of the state of Utah. In 2002, then-governor Mike Leavitt of Utah proposed the creation of a San Rafael Swell National Monument. President George Bush, who has authority to create such a National Monument under the Antiquities Act, has yet to act on Leavitt's proposal as of 2006.


The San Rafael Swell attracts hikers, backpackers, horseback riders, and all-terrain vehicle (ATV) enthusiasts. Many steep, narrow slot canyons popular with technical canyoneers are found in the San Rafael Reef. The use of ATVs in the Swell is controversial, as environmentalists draw attention to the fact that off-road vehicles damage the fragile desert cryptobiotic soils.

Goblin Valley State Park is on the southeastern edge of the San Rafael Swell.


* Allen, Steve, "Canyoneering: The San Rafael Swell", 1992. ISBN 0-87480-372-1
* Durrant, Jeffrey O. "Struggle Over Utah's San Rafael Swell: Wilderness, National Conservation Areas, and National Monuments", 2007. ISBN 978-0-8165-2669-7
* Kelsey, Michael R. "Hiking and Exploring Utah's San Rafael Swell", 3rd edition, 1999. ISBN 0-944510-17-5

External links

* [ BLM - Utah]
* [,-110.657043&spn=1.022022,1.776901&t=h&hl=en satellite image & map from Google Local]
* []
* []
* [ San Rafael Swell - Utah -]

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • San Rafael swell cactus — taškuotoji pėdulė statusas T sritis vardynas apibrėžtis Kaktusinių šeimos augalas (Pediocactus despainii), paplitęs Jutoje. atitikmenys: lot. Pediocactus despainii angl. Despain s cactus; Despain s foot cactus; Despain s pincushion cactus; San… …   Lithuanian dictionary (lietuvių žodynas)

  • San Rafael River — The San Rafael River is a tributary of the Green River, approximately 90 miles (145 km) long, in east central Utah in the United States. The river flows across a sparsely populated arid region of the Colorado Plateau, and is known for the… …   Wikipedia

  • San Rafael Reef — The San Rafael Reef is a geologic feature located in Emery County in central Utah, part of the Colorado Plateau. Approximately 75 miles (120 km) long, it is the name given to the distinctive eastern edge of the San Rafael Swell. Composed… …   Wikipedia

  • San Rafael Group — The San Rafael Group is a geologic group of formations that is spread across the U.S. states of New Mexico, Arizona, Utah and Colorado. Part of the Colorado Plateau, this group of formations was laid down in the Middle Jurassic during the… …   Wikipedia

  • San Rafael cactus — taškuotoji pėdulė statusas T sritis vardynas apibrėžtis Kaktusinių šeimos augalas (Pediocactus despainii), paplitęs Jutoje. atitikmenys: lot. Pediocactus despainii angl. Despain s cactus; Despain s foot cactus; Despain s pincushion cactus; San… …   Lithuanian dictionary (lietuvių žodynas)

  • San Joaquin River — Coordinates: 38°04′00″N 121°51′04″W / 38.0666667°N 121.85111°W / 38.0666667; 121.85111 …   Wikipedia

  • Interstate 70 in Utah — Infobox road state=UT type=I route=70 section=112 maint=UDOT map notes=Highways in Utah with I 70 highlighted in red length mi=232.15 length round=2 length ref=cite web|url=|title=FHWA Route… …   Wikipedia

  • Muddy Creek (Utah) — Muddy Creek is a stream which drains portions of Emery and Wayne Counties in central Utah, in the western United States. It begins on the eastern slopes of the Wasatch Plateau at elevations above 10,500 feet (3200 m). It turns southward near the… …   Wikipedia

  • Interstate 70 — Infobox road type=I route=70 length mi=2153.13 length round=2 length ref=cite web |url=|title=Route Log Main Routes of the Eisenhower National System of Interstate and Defense Highways Table… …   Wikipedia

  • Emery County, Utah — Infobox U.S. County county = Emery County state = Utah seallink = map size = 150 founded year = 1880 seat wl = Castle Dale largest city wl = Huntington area total sq mi = 4462 area total km2 = 11555 area land sq mi = 4452 area land km2 = 11530… …   Wikipedia