Upheaval Dome is an enigmatic geological structure in San Juan County,

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

, that has been variously interpreted as a meteorite

impact structure An impact structure is a generally circular or craterlike geologic structure of deformed bedrock or sediment produced by impact on a planetary surface, whatever the stage of erosion of the structure. In contrast, an impact crater is the surfa ...

or a

salt dome A salt dome is a type of structural dome formed when salt (or other evaporite minerals) intrudes into overlying rocks in a process known as diapirism. Salt domes can have unique surface and subsurface structures, and they can be discovered usi ...

. The structure lies southwest of the city of

Moab, Utah Moab () is the largest city and county seat of Grand County in eastern Utah in the western United States, known for its dramatic scenery. The population was 5,366 at the 2020 census. Moab attracts many tourists annually, mostly visitors to ...

, in the Island in the Sky section of

Canyonlands National Park Canyonlands National Park is an American national park located in southeastern Utah near the town of Moab. The park preserves a colorful landscape eroded into numerous canyons, mesas, and buttes by the Colorado River, the Green River, and their ...

Description

Upheaval Dome is approximately in

diameter In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle. Both definitions are also valid f ...

and the crater is known to be less than 170 million years old (

Jurassic The Jurassic ( ) is a geologic period and stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately Mya. The Jurassic constitutes the middle period of ...

or younger, but how much younger is not established.) The crater is clearly visible on the surface as light and dark brown concentric rings. Stratigraphically, the oldest formation exposed in the center of the dome is the

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleo ...

Organ Rock Shale. This is overlain by the Permian

White Rim Sandstone The White Rim Sandstone is a sandstone geologic formation located in southeastern Utah. It is the last member of the Permian Cutler Group, and overlies the major Organ Rock Formation and Cedar Mesa Sandstone; and again overlies thinner units ...

. Both are sometimes considered part of the

Cutler Formation The Cutler Formation or Cutler Group is a rock unit that is exposed across the U.S. states of Arizona, northwest New Mexico, southeast Utah and southwest Colorado. It was laid down in the Early Permian during the Wolfcampian epoch. Descri ...

. Overlying these are the

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest per ...

Moenkopi Formation The Moenkopi Formation is a geological formation that is spread across the U.S. states of New Mexico, northern Arizona, Nevada, southeastern California, eastern Utah and western Colorado. This unit is considered to be a group in Arizona. ...

(which is bounded top and bottom by unconformities), the

Chinle Formation The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In N ...

, the cliff-forming

Wingate Sandstone The Wingate Sandstone is a geologic formation in the Glen Canyon Group of the Colorado Plateau province of the United States which crops out in northern Arizona, northwest Colorado, Nevada, and Utah. Geology Wingate Sandstone is particularl ...

, the

Kayenta Formation The Kayenta Formation is a geological formation in the Glen Canyon Group that is spread across the Colorado Plateau province of the United States, including northern Arizona, northwest Colorado, Nevada, and Utah. Traditionally has been suggested ...

, and the

crossbedded In geology, cross-bedding, also known as cross-stratification, is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal units composed of inclined layers. The origina ...

Triassic-Jurassic Navajo Sandstone.Geologic Map of Canyonlands National Park and Vicinity, Utah, 1982 Edition, by P. W. Huntoon et al. Scale: 1:62500 (map) Structurally, the dome is anomalous. Most of the rock strata of Canyonlands National Park are flat-lying or gently dipping with the exception of a series of linear salt walls and associated synclines. Upheaval Dome is a circular, dome shaped structure. Some strata near the center are nearly vertical in orientation. Dips of 70 degrees have been measured in the Kayenta Formation on the U-shaped plateau surrounding the center of the structure. A

syncline In structural geology, a syncline is a fold with younger layers closer to the center of the structure, whereas an anticline is the inverse of a syncline. A synclinorium (plural synclinoriums or synclinoria) is a large syncline with superimpose ...

surrounds the center, where the axis forms a complete circle approximately two miles across. The syncline is primarily visible in the Navajo Sandstone. Another

anticline In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is t ...

has been mapped to the north of this ring syncline, which is also concentric with it. There were two well-known theories as to the origin of the upheaval. One theory was the upheaval is a

, an anticlinal structure which occurs when a salt

diapir A diapir (; , ) is a type of igneous intrusion in which a more mobile and ductily deformable material is forced into brittle overlying rocks. Depending on the tectonic environment, diapirs can range from idealized mushroom-shaped Rayleigh–T ...

is pushed up by the weight of overlying rocks. The other theory is an eroded impact crater, like the much younger

Meteor Crater Meteor Crater, or Barringer Crater, is a meteorite impact crater about east of Flagstaff and west of Winslow in the desert of northern Arizona, United States. The site had several earlier names, and fragments of the meteorite are offi ...

near Winslow, Arizona. In the 1990s, a team of

geologist A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, althou ...

s and seismologists from

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeedin ...

and the

University of Nevada The University of Nevada, Reno (Nevada, the University of Nevada, or UNR) is a public land-grant research university in Reno, Nevada. It is the state's flagship public university and primary land grant institution. It was founded on October 12 ...

Reno Reno ( ) is a city in the northwest section of the U.S. state of Nevada, along the Nevada-California border, about north from Lake Tahoe, known as "The Biggest Little City in the World". Known for its casino and tourism industry, Reno is th ...

performed a detailed study that included seismic refraction and rock mapping. The results of this study support the

meteorite A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or moon. When the original object ...

theory.Earth Impact DB - Upheaval Dome
/ref> In 2008, it was announced that shocked quartz was discovered, although this was very limited and the origin remains unresolved.

Gallery

Image:Upheaval_Dome_air.jpg, Oblique air photo facing southeast from about 30,000 ft. Image:Upheaval Dome.jpg, Upheaval Dome as seen from the rim of the crater. Image:Upheaval_Syncline_campsite.jpg,

Syncline In structural geology, a syncline is a fold with younger layers closer to the center of the structure, whereas an anticline is the inverse of a syncline. A synclinorium (plural synclinoriums or synclinoria) is a large syncline with superimpose ...

in Navajo Sandstone visible from the Syncline Campsite on the northwest side of the structure, facing south Image:Upheaval_center.jpg, Steeply dipping rock strata near the center of the dome

References

External links

Upheaval dome on PASSC Earth Impact Database

* ttp://dsc.discovery.com/news/2008/03/11/upheaval-dome-utah-print.html Shocked Quartz discovery
Aerial Exploration of the Upheaval Dome impact crater
{{Impact cratering on Earth Impact craters of the United States Jurassic impact craters Canyonlands National Park Landforms of San Juan County, Utah