San Rafael Swell

Information about 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.

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Interstate 70 divides the San Rafael Swell

Geography

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.

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San Rafael Reef

Geology

Main article: Geology of the Capitol Reef area


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.

History

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.

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Entrance to the Muddy Creek Gorge

Administration

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. 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.

Recreation

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.

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Goblin Valley State Park

References

  • 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

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State of Utah
Salt Lake City (capital)
Cities | Counties | Flag | Flower | Governors | | Song
Regions Cache Valley | Colorado Plateau | Dixie | Great Basin | Great Salt Lake | Great Salt Lake Desert | Mojave Desert | Monument Valley | San Rafael Swell | Uinta Mountains | Wasatch Back | Wasatch Front | Wasatch Range
Largest Cities American Fork | Bountiful | Cedar City | Clearfield | Cottonwood Heights | Draper | Holladay | Kaysville | Layton | Lehi | Logan | Midvale | Murray | Ogden | Orem | Pleasant Grove | Provo | Riverton | Roy | St. George | Salt Lake City | Sandy | South Jordan | South Salt Lake | Spanish Fork | Springville | Taylorsville | Tooele | West Jordan | West Valley City
Counties Beaver | Box Elder | Cache | Carbon | Daggett | Davis | Duchesne | Emery | Garfield | Grand | Iron | Juab | Kane | Millard | Morgan | Piute | Rich | Salt Lake | San Juan | Sanpete | Sevier | Summit | Tooele | Uintah | Utah | Wasatch | Washington | Wayne | Weber
Attractions Arches National Park | Bonneville Salt Flats | Bryce Canyon National Park | Canyonlands National Park | Capitol Reef National Park | Great Salt Lake | Ski Areas | Sundance Film Festival | Temple Square | Utah Shakespearean Festival | Zion National Park
Oceanic crust      0-20 Ma
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State of Utah

Flag of Utah Seal
Nickname(s): Beehive State
Motto(s): "Industry"

Official language(s) English

Capital Salt Lake City
Largest city Salt Lake City

Area
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Motto
"In God We Trust"   (since 1956)
"E Pluribus Unum"   ("From Many, One"; Latin, traditional)
Anthem
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Green River, Utah

Seal
Motto:
Location of Green River, Utah
Coordinates:
Country United States
State Utah
Counties Emery, Grand
Area
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anticline is a fold that is convex up or to the youngest beds.

On a geologic map, anticlines are usually recognized by a sequence of rock layers that are progressively older toward the center of the fold because the uplifted core of the fold is preferentially eroded to a
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worldwide view of the subject.
Please [ improve this article] or discuss the issue on the talk page.
| A flash flood is a rapid flooding of geomorphic low-lying areas (washes), rivers and streams, caused by the intense rainfall associated with a thunderstorm, or
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Sedimentary rock is one of the three main rock groups (the others being igneous and metamorphic rock). Rock formed from sediments covers 75-80% of the Earth's land area, and includes common types such as chalk, limestone, dolomite, sandstone, conglomerate and shale.
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geology, a valley is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.

The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys.
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canyon (rarely cañon) or gorge is a deep valley between cliffs often carved from the landscape by a river. Most canyons were formed by a process of long-time erosion from a plateau level.
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canyon (rarely cañon) or gorge is a deep valley between cliffs often carved from the landscape by a river. Most canyons were formed by a process of long-time erosion from a plateau level.
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mesa (Spanish and Portuguese for "table") is an elevated area of land with a flat top and sides that are usually steep cliffs. It takes its name from its characteristic table-top shape.
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A butte (IPA: /bju:t/) is an isolated hill with steep sides and a small flat top, smaller than mesas and plateaus. Buttes are prevalent in the western United States and on the Hawaiian Islands, especially around Honolulu.
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The Colorado Plateau, also called the Colorado Plateaus Province, is a physiographic region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States.
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U. S. physiographic regions within the continental United States. Each is composed of smaller physiographic subdivisions.

These eight regions are:
  • Canadian Shield (area labeled 1)
  • Atlantic Plain (2 and 3)
  • Appalachian Highlands (4-10)

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Main route of the Interstate Highway System

2153.13 mi[1] (0 km)
1956 (completed in 1992)

I-15 near Cove Fort, UT

I-25 in Denver, CO
I-35 in Kansas City, MO
I-55 in St.
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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 isolated, scenic gorge through which it flows.
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The Dirty Devil River is a tributary of the Colorado River, approximately 80 mi (129 km) long, in south central Utah in the United States.

It is formed in Wayne County near Hanksville from the confluence of the Fremont River and Muddy Creek.
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Hanksville is a small town located in Wayne County, Utah, at the junction of Utah State Route 24 and Utah State Route 95. The town is just south of the confluence of the Fremont River and Muddy Creek, which together form the Dirty Devil River, which then flows southeast to
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Mouth Gulf of California
Basin countries United States, Mexico
Length 2,330 km (1,450 mi)
Source elevation ~2700 m (~9000 ft)

Avg. discharge 620 m³/s (22,000 ft³/s)[1]
Basin area 629,100 km² (242,900 mi²)
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Green River is a tributary of the Colorado River, 730 mi (1,175 km) long, in the western United States. The Green River Basin covers parts of Wyoming, Utah, and Colorado.
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Muddy Creek is a stream draining 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).
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The Fremont River in Utah flows from the Johnson Valley Reservoir near Fish Lake southwest through Capitol Reef National Park to the Muddy Creek near Hanksville where the two rivers combine to form the Dirty Devil River, a tributary of the Colorado River.
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geology of the Capitol Reef area presents a record of mostly Mesozoic-aged sedimentation in an area of North America in and around Capitol Reef National Park. Nearly 10,000 feet (3,000 m) of sedimentary strata are found in the Capitol Reef area, representing nearly 200
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Precambrian (Pre-Cambrian) is an informal name for the supereon comprising the eons of the geologic timescale that came before the current Phanerozoic eon. It spans from the formation of Earth around 4500 Ma (million years ago) to the evolution of abundant
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fault or fault line is a planar rock fracture, which shows evidence of relative movement. Large faults within the Earth's crust are the result of shear motion and active fault zones are the causal locations of most earthquakes.
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The Laramide orogeny was a period of mountain building in western North America, which started in the Late Cretaceous, 70 to 80 million years ago, and ended 35 to 55 million years ago. The exact duration and ages of beginning and end of the orogeny are in dispute, as is the cause.
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Fold may refer to:
  • above the fold
  • Sheepfold, an enclosure for sheep
  • fold, a family of higher-order functions in functional computer programming
  • fold, a program in the GNU Core Utilities
  • fold catastrophe, one most basic objects in singularity theory.

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anticline is a fold that is convex up or to the youngest beds.

On a geologic map, anticlines are usually recognized by a sequence of rock layers that are progressively older toward the center of the fold because the uplifted core of the fold is preferentially eroded to a
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stratum (plural: strata) is a layer of rock or soil with internally consistent characteristics that distinguishes it from contiguous layers. Each layer is generally one of a number of parallel layers that lie one upon another, laid down by natural forces.
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The Jurassic Period is a major unit of the geologic timescale that extends from about 199.6 ± 0.6 Ma (million years ago) to 145.4 ± 4.0 Ma, the end of the Triassic to the beginning of the Cretaceous.
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