Terrain here is flat compared with Basin and Range country to the west and the Rocky Mountains to the east. Yet wind and water have whittled Plateau rock into dramatic cliffs and steps as well as fanciful domes, towers, turrets, and arches.
The Plateau is dissected by the Colorado River and its tributaries exposing a deep and colorful geologic history.
The color of rock is primarily influenced by trace minerals. The red, brown, and yellow colors so prevalent in southern UT result from the presence of oxidized iron—that is iron that has undergone a chemical reaction upon exposure to air or oxygenated water. The iron oxides released from this process form a coating on the surface of the rock or rock grains containing the iron. Take, for instance, the Navajo sandstone that makes up the sheer cliffs ofZionNational Park. During the Jurassic Period — about million years ago — this area was covered by a vast desert.
If you look at a piece of Navajo sandstone under a microscope, the grains themselves are still white, gray or tan, but the grains are completely coated with the hematite cement, giving the appearance that the rock is totally red. Answer: It has to do with the particles of ash floating around in the atmosphere during a wildfire. The sky gets its colors from light reflected off particles in the atmosphere.
On a clear day, most of the particles in the air are just the right size to reflect the short wavelengths of the blue end of the spectrum. The blue light is scattered through the air instead of passing through it, giving the sky its blue color.
Utah's largest true deserts are Canyonland and the Great Basin area. Steppe areas, making up about 40 percent of Utah, occur between desert margins and higher mountain regions. What was Utah called before it became a state? Utah's very interesting path to statehood.
On this day in , Utah became the 45th state, after numerous attempts over nearly 50 years to achieve statehood. In those living in the Utah Territory petitioned to become part of the Union as the state of Deseret. What part of America is Utah in? The capital, Salt Lake City, is located in the north-central region of the state. The state lies in the heart of the West and is bounded by Idaho to the north, Wyoming to the northeast, Colorado to the east, Arizona to the south, and Nevada to the west.
What is the capital in Utah? Salt Lake City. What is the landscape of Utah? For hundreds of miles, the landscape is dominated by twisting canyons, delicate arches, sheer mountains and ridges, spires and buttes. More than any other Southwest state, Utah provides the archetypal Western images of sandy desert, deep canyons and towering red rocks.
Salt Lake City Ogden. Is Utah part of California? Sediments shed from the eastern side of these newly created highlands formed a wedge of conglomerates and sandstones across central Utah. These graded onto the gentler, coastal-plain topography of eastern Utah, that looked much like present-day Texas and gradually stretched into a broad, shallow seaway.
Extensive swamps, now Utah's richest coal deposits, flourished along the margin of the seaway and the slow-moving, gentle-gradient rivers of the coastal plain. The sedimentary rocks deposited during this phase cover much of central and eastern Utah and grade from coarse conglomerates to the dull gray shales deposited in the shallow Mancos seaway.
These shales erode easily and have provided today's transportation and utility corridors from Colorado into Utah. The sixth phase's uplifting of the Uinta Mountains and downwarping of the Uinta Basin resulted from the creation of the Rocky Mountains.
Lakes occupied large basins east of the Wasatch line. The Green River lake beds were in one of these basins, and now are an important source of oil and oil shale. Much of the area not covered by these lakes eroded. The seventh phase must have been rather exciting. A period of widespread igneous activity began about 40 million years ago.
Caldera explosions erupted thousands of cubic miles of volcanic rocks from several locations. Volcanoes spewed ash and lava. For 20 million years these extrusive volcanic rocks smoothed the landscape, filling depressions with accumulations of ash, flows, and debris literally miles thick. These mostly pastel-colored extrusive rocks still blanket much of the high areas of central and southwestern Utah. During this seventh phase, not all of the molten rising igneous material erupted as volcanic rocks; some material, along with its mineral-bearing fluids, congealed in the earth's crust.
Several of these intruded masses having been exposed by erosion or encountered out by exploration drilling became great mining districts, such as at Alta, Brighton, Bingham, Park City, and Cedar City.
In the Colorado Plateau, bodies of intrusive rocks domed the overlying sedimentary rocks to form the La Sal, Abajo, and Henry Mountains.
The eighth phase created our present topography. Regional uplift of much of the western North American continent raised Utah to its present elevation, on average about one mile above sea level.
Steepened river gradients greatly accelerated erosion, and several rivers still sculpt the great canyonlands of the Colorado Plateau and carry incredible volumes of sediment to the Colorado River toward the Gulf of California.
As the western coast of the North American continent moves slowly westward relative to the continent east of the Wasatch line, the east-west stretching has broken the crust along north-south faults, creating elongated basins and ranges, disrupting drainages, isolating mountain ranges, and creating closed basins that have been filling with sediments ever since. Active faults such as the Wasatch fault accommodate this stretching and tilting in jarring, potentially destructive readjustments called earthquakes.
Volcanism continues, particularly in southwestern Utah. Substantially cooler and wetter climate periods created glaciers at high elevations and lakes in basins. One such was Lake Bonneville, which reached its highest level, in places more than 1, feet deep, about 15, years ago.
Significantly drier conditions intervened. Today we live in one of the drier periods. The glaciers have retreated and hotter conditions have almost dried up the extensive lakes, leaving the Great Salt Lake as the largest remnant of the lake that once covered most of northwestern Utah.
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