POPULAR GEOLOGY

Landforms

The earth’s surface is constantly remodeled by various geological processes. The changes are one of the most exciting things about geology—not only are they continuous, but in many cases, observable. Some geological processes, such as those that make mountains or wear them down, typically take place at imperceptible rates. Sudden events, however, can change the landscape in a minute (for example, a single earthquake can create a 10-foot-high [3 meter] fault scarp, alter stream courses, and drop the valley floor 3 feet [1 meter]).

Utah is the ideal place to observe geology in action. The state contains many types of landforms, such as mountains, plateaus, mesas, river-eroded canyons, glacier-eroded canyons, volcanoes, and basins.

Crustal plate movement, mountain building (except some volcanic mountain building), and erosion are part of the slow evolution of Earth’s landscape. This evolution is sporadically interrupted by more sudden geological events, such as earthquakes (following the Borah Peak, Idaho earthquake in 1983, the mountain range rose 8 inches [20 centimeters], and the adjacent valley dropped about 4 feet [1.2 meters]) and volcanic activity (in Mexico in 1943, a volcano called Paricutin appeared in a farmer’s field and rose 525 feet [160 meters] within a week). Erosion can also happen quite suddenly, and in some cases, may be greatly accelerated by human activities. Flash floods can erode more than 10 inches (25 centimeters) of soil in only a few hours.

By observing landforms, we can learn where geological processes, including erosion, mountain building, crustal extension, earthquakes, geothermal activity, landslides, and rockfalls are currently active in Utah.

Mountains

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Glaciers

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Volcanoes

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Earthquake-Related Landforms

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Plateaus

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Arches

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Physiographic Provinces

Generalized map of Utah’s physiographic provinces.

Basin and Range Province

Steep, narrow, north-trending mountain ranges separated by wide, flat, sediment-filled valleys characterize the topography of the Basin and Range Province. The ranges started taking shape around 17 million years ago when the previously deformed Precambrian (over 540 million years old) and Paleozoic (~540 to ~250 million years old) rocks were slowly uplifted and broken into huge fault blocks by extensional stresses that continue to stretch the earth’s crust.

Colorado Plateau Province

In contrast with the Basin and Range Province, a thick sequence of largely undeformed, nearly flat-lying sedimentary rocks characterize the Colorado Plateau province. Erosion sculpts the flat-lying layers into picturesque buttes, mesas, and deep, narrow canyons.

For hundreds of millions of years sediments have intermittently accumulated in and around seas, rivers, swamps, and deserts that once covered parts of what is now the Colorado Plateau. Starting about 10 million years ago the entire Colorado Plateau slowly but persistently began to rise, in places reaching elevations of more than 10,000 feet (3,000 meters) above sea level. Miraculously it did so with very little deformation of its rock layers. With uplift, the erosive power of water took over to sculpt the buttes, mesas, and deep canyons that expose and dissect this “layer cake” of sedimentary rock.

Middle Rocky Mountains Province

High mountains carved by streams and glaciers characterize the topography of the Middle Rocky Mountains province. The Utah part of this province includes two major mountain ranges, the north-south-trending Wasatch and east-west-trending Uintas. Both ranges have cores of very old Precambrian rocks, some over 2.6 billion years old, that have been altered by multiple cycles of mountain building and burial.

Basin and Range – Colorado Plateau Transition Zone

The Basin and Range–Colorado Plateau transition zone is a broad region in central Utah containing structural and stratigraphic characteristics of both the Basin and Range Province to the west and the Colorado Plateau province to the east.

The boundaries are the subject of some disagreement, resulting in various interpretations using different criteria. Essentially, extensional tectonics of the Basin and Range has been superimposed upon the adjacent coeval uplifted blocks of the Colorado Plateau and Middle Rocky Mountains. The result is that block faulting, the principal feature of the Basin and Range, extends tens of kilometers into the adjacent provinces forming a 100-km-wide (60 mi) zone of transitional tectonics, structure, and physiography.


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Physiographic Provinces

Public Interest Articles

Search:
TitleTopicYear
G.K. Gilbert Geologic View Park, Salt Lake County Landforms 2008
The Onion Creek Salt Diapir, Grand County Landforms 2008
Ancient Exhumed River Channels of the Morrison and Cedar Mountain Formations Geologic History 2008
The Dome/ Diapir/ Dome Mountain Dilemma Mountains 2008
What are “Potholes” and how are organisms able to live in them? Landforms 2007
Sand Dunes on the Navajo Sandstone at Sand Mountain, Washington County Landforms 2007
Spectacular Towering Cliffs at Castle Rock Campground, Sevier County Volcanoes 2006
Devils Playground, Box Elder County Landforms 2006
What Utah mountain range honors prominent geoscientists of the 19th century and who were they? Mountains 2005
The Amazing Monoliths and “Mountain” of Gypsum at Lower Cathedral Valley, Capitol Reef National Park, Wayne County Landforms 2005
The Traverse Mountains Mountains 2005
Fisher Towers – The Towering Red Rock Sculptures of Grand County Landforms 2004
Sand Dunes at Little Sahara Recreation Area, Juab County Landforms 2004
Big Rock Candy Mountain – A Colorful Reminder of Utah’s Volcanic Past Volcanoes 2003
Nature’s Version of a Playground Slide – Devils Slide, Morgan County Landforms 2003
Little Egypt Geologic Site, Hoodoos of Garfield County Landforms 2002
Inverted Topography in the St. George Area of Washington County Volcanoes 2002
Pahvant Butte in the Black Rock Desert Volcanoes 2002
San Rafael Swell proposed as new national monument Landforms 2002
Rainbow of Rocks: mysteries of sandstone colors and concretions in Colorado Plateau Canyon Country (pdf) Rocks and Minerals 2002
Natural Arches in the Cedar City Area, Iron County Arches 2001
What is a formation? Landforms 2001
Why is the Wasatch Front “blessed” with abundant sand, gravel, and rock? Rocks and Minerals 2001
What is a rock formation? Geologic History 2001
Utah’s Sevier Thrust System Geologic History 2000
How was Utah’s topography formed? (major physiographic provinces) Landforms 2000
Dome Mountains (Activity for 3rd grade) Mountains 2000
Sinkholes in Big Round Valley, Washington County Landforms 2000
The geology of Goblin Valley State Park (pdf) Landforms 1999
The geology of Quail Creek State Park (pdf) Landforms 1999
What is the Grand Staircase? (pdf) Landforms 1999
Geologic Stretching – How many inches per year do Salt Lake City, Utah and Reno, Nevada move away from each other? Landforms 1997
Utah Caves (pdf) Landforms 1996
The Earth’s Surface, the only Constant is Change. Landforms 1994
The geology of Snow Canyon State Park, Washington County, Utah (pdf) Volcanoes 1992
Mill Creek Canyon Mountains 1991
Little Cottonwood Canyon Mountains 1991
Emigration Canyon and Lower Parleys Canyon Mountains 1991
City Creek Canyon Mountains 1991
Big Cottonwood Canyon Mountains 1991
Geology and scenery of the central Wasatch Range, Salt Lake and Summit Counties; road log (pdf) Mountains 1991
Landforms Presentation (PowerPoint) Landforms

Landforms Articles: 92