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54-531: The Wasatch Range or Wasatch Mountains is a mountain range in the western United States. Wasatch may also refer to: Wasatch Range In the language of the native Ute people , Wasatch means "mountain pass" or "low pass over high range." According to William Bright , the mountains were named for a Shoshoni leader who was named with the Shoshoni term wasattsi , meaning "blue heron". In 1926, Cecil Alter quoted Henry Gannett from 1902, who said that

108-585: A fold-thrust belt on a regional scale. At the local scale segments of the belt are connected by transverse zones. The Charleston transverse zone mentioned earlier runs perpendicular to the thrust faults within the Sevier belt. It has been debated among geologists if this transverse zone developed during the Sevier orogeny or the Uinta/Cottonwood arch formation during the Laramide orogeny . Mapping Sevier thrusting in

162-557: A lush understory of wildflowers and grasses. Wyoming big sagebrush ( Artemisia tridentata ssp. wyomingensis ) occurs at the lowest and driest elevations, although much of the Wasatch Range is above the elevation where this subspecies occurs. All sagebrush species, combined, provide critical habitat to greater sage grouse , a species under consideration for listing by the United States Fish and Wildlife Service . The Wasatch Range

216-682: Is common on the foothills of the range from just south of Brigham City in the north, to the southern extension of the Wasatch Range. It is not found in the northern portion of the Range. Ponderosa pine ( Pinus ponderosa ), while abundant elsewhere in Utah is not common in this mountain range, except in plantations in Big Cottonwood Canyon southeast of Salt Lake City and in Logan Canyon , east of Logan. Some individual trees have been found in remote areas of

270-585: Is especially gentle compared to the rest of the range. The range widens east of Ogden, sheltering a high mountain valley known as the Ogden Valley. Three more ski resorts lie here, as well as several small towns (such as Huntsville , Liberty , and Eden ). North of this, the Wellsville Mountains branch off from the northwest of the range, continuing a line of mountains paralleling the I-15 corridor. This range

324-528: Is evidence that suggests late Sevier faults were active during the early Laramide.   The majority of Sevier deformation occurred west of Laramide deformation, but there is some geographic overlap between the eastern Sevier margin and the western Laramide margin. In southwestern Utah, Sevier thrusts may have remained active until the Eocene, while Laramide deformation began in the Late Cretaceous . Since

378-769: Is exceptionally thin and steep. However, US-89 / US-91 is maintained as a four-lane highway through the range at Wellsville Canyon east of Brigham City . Cache Valley , created by the Bear River , is flanked on the west by the Wellsville Mountains and on the east by the much denser and higher Bear River Mountains. The northwestern border of Cache Valley is flanked by the Bannock Range in Idaho . The two highest peaks in this area are Mount Naomi and Mount Logan , each just under 10,000 feet (3,000 m). The southeastern portion of

432-489: Is home to a high concentration of ski areas, with 11 stretching from Sundance in northeastern Utah County to Powder Mountain and Nordic Valley Ski Area northeast of Ogden . There are also two ski resorts in the Bear River Mountains ( Beaver Mountain and Cherry Peak Resort ). Park City alone is bordered by two ski resorts. Due to the low relative humidity in wintertime, along with the added lake-effect from

486-529: Is home to several plants that occur nowhere other than in this area. Several of these are rare and restricted to narrow geological formations, while others are more widely distributed throughout the area. Some of the less rare endemics include five-petal cliffbush ( Jamesia americana var. macrocalyx ), Sierra fumewort ( Corydalis caseana ssp. brachycarpa ), and Utah angelica ( Angelica wheeleri ). In addition to ski resorts, there are hundreds of miles of mountain biking and hiking trails winding through

540-415: Is thought to be a parallel model of the Sevier and Laramide events so there are possibly answers to this question in this modern model. Explanations may include a combination of plate motion rates increasing, the underriding oceanic plate becoming younger as the older portion subducts, and thus the underriding plate being hotter and more buoyant. A study on calcite twinning and carbonate relationships with

594-799: The Basin and Range Province suggests Sevier structures curve around the Uinta/Cottonwood arch defining the Uinta recess. Looking closely at Sevier faults in American Fork Canyon indicate that these faults are the oldest in the Charleston transverse zone suggested by cross cutting relationships observed in the area. The Basin and Range Province extending across Nevada , into western Utah , and south into Mexico now consists of N-S normal faulting due to crustal extension. If these normal faults show any extension in late Eocene to early Miocene , this could be evidence

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648-542: The Pfeifferhorn . Farther north, Big Cottonwood Canyon features tricky climbing on quartzite . The densely vegetated narrow canyons of the Wasatch Range, such as Big Cottonwood Canyon and Little Cottonwood Canyon, are heavily visited; on 25 September 2005, 1,200 automobiles entered Little Cottonwood in an hour. The canyons sit within 24 miles (39 km) of downtown Salt Lake City and the year-round paved roadways can reach 5,000 feet (1,500 m) higher in elevation above

702-697: The Rocky Mountains of Colorado or even the Uinta Mountains (the other main portion of the Rocky Mountains in Utah). However, they are sculpted by glaciers, yielding notably rugged, sweeping upland scenery. They also receive heavy snowfall: more than 500 inches (1,300 cm) per year in some places. This great snowfall, with its runoff, made possible a prosperous urban strip of some 25 cities along nearly 100 miles (160 km) of mountain frontage. The Wasatch Range

756-592: The Union Pacific Railroad , the line is used by freight trains and Amtrak 's California Zephyr . The Wasatch Range is part of the Wasatch and Uinta Mountains Level 3 Ecoregion, a temperate coniferous forest . Common trees include Douglas fir ( Pseudotsuga menziesii ), subalpine fir ( Abies bifolia ), Engelmann spruce ( Picea engelmannii ), Colorado blue spruce ( Picea pungens ), and quaking aspen ( Populus tremuloides ). Gambel oak ( Quercus gambelii )

810-635: The Cordilleran passive margin east. The Sevier meets the Laramide orogenic belt on its eastern side. The Sevier and Laramide combination is similar to the modern day Andean margin in Chile . They are comparable because the younger Laramide faults and structures were a geometric response to the shallow dipping Sevier thrusts. The location of the eastern edge of the Sevier orogeny was determined by conglomerates largely made up of boulders that would have been shed from

864-554: The Garden Valley thrust system has a direct link to the Sevier thrust belt. The interpretation of this data led to the central Nevada thrust belt as being an interior section of the Sevier. This correlation provides evidence that the Sevier thrust belt was a result of compression moving eastward through the North American plate. Thinning of the Cordilleran has previously been thought to be evidence and reason for flat subduction in

918-588: The Great Salt Lake, the snow has a dry, powdery texture which most of the local ski resorts market as "the Greatest Snow on Earth". The snow and nearby ski resorts helped Salt Lake City gain the right to host the 2002 Winter Olympics . Several of the canyons in the Lone Peak area, most notably Little Cottonwood Canyon , have several high-quality granite outcroppings, and make up a popular climbing area such as

972-511: The Jurassic and Paleogene, the regional stress regime became a maximum striking east to west. This horizontal compression caused thin skinned imbricated thrust faults resulting in as much as 50% crustal shortening of the western North American Plate. The Wasatch anticlinorium represented the furthest eastern margins of these Sevier origin imbricated thrusts. Once the Farallon plate had largely subducted,

1026-492: The Laramide orogenic event. Sevier shortening has been recorded throughout much of the western United States as far east as Minnesota in the Cretaceous Greenhorn Limestone as preserved by calcite twinning. The distance of stress transfer is roughly equivalent to more than 2000 km. The E-W shortening shown in calcite twinning of the Sevier is parallel to today's principal stresses in the western interior of

1080-602: The Mexican border to Canada. Basin and Range faults cut the older Sevier thrust faults. The Sevier orogeny was preceded by several other mountain-building events including the Nevadan orogeny , the Sonoman orogeny , and the Antler orogeny , and partially overlapped in time and space with the Laramide orogeny . Early Sevier thrusting began well before initial Laramide deformation. However, there

1134-564: The NW moving Pacific plate latched onto the North American Plate, causing a change in regional stress. Sevier thrust ramps were reactivated into normal faults, causing crustal extension as the Pacific plate drags the western margins of the North American plate to the NW. The current Wasatch range continues to grow via normal faults as the valley drops in periodic motion. Mount Nebo, the highest peak of

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1188-626: The North American plate. Voluminous volcanism is also associated with the Sevier Orogeny. Volcanic activity can be observed at modern subduction zones, (such as along the west coast of South America) like the one that caused the Sevier Orogeny. Several volcanic flare-ups occurred in the Sierra Nevada arc, associated with the Sevier Orogeny: one from 170 Ma to 150 Ma, and one from 100 Ma to 85 Ma. Volcanic centers migrated generally eastward during

1242-693: The Salt Lake Valley, shelters small mountain coves that harbor four world-famous ski resorts ( Alta , Brighton , Solitude , and Snowbird ). The eastern slopes of the Cottonwoods drop to the Snyderville Basin , which contains Park City and its two ski resorts ( Park City Mountain Resort and Deer Valley ). Much of the eastern side of the range, from north of Salt Lake City to the Bear River Mountains,

1296-498: The Sevier and Laramide orogenic events. However, isotopic data suggests that preservation of Cordilleran lithosphere implies Cordilleran thinning is not a sufficient answer for Sevier and Laramide flat subduction. This implies thinning and shearing of the Cordilleran was confined to the fore-arc region. Data suggests throughout the Sevier-Laramide thrusting the crust was also uplifted and extended. The modern Chilean subduction

1350-456: The Sevier and Laramide orogenies occurred at similar times and places, they are sometimes confused. In general the Sevier orogeny defines an older, more western compressional event that took advantage of weak bedding planes in overlying Paleozoic and Mesozoic sedimentary rock. As the crust was shortened, pressure was transferred eastward along the weak sedimentary layers, producing “ thin-skinned ” thrust faults that generally get younger to

1404-569: The Sevier are located furthest west with each newer thrust cutting the older thrust. This pattern caused the older thrusts to ride on top of the younger thrusts as they moved eastward. The Paris-Willard thrust in Utah was determined to be the oldest thrust in the series using this pattern. The youngest thrust is the Hogback in Wyoming. The Sevier thrust belt in Utah can be divided in two, north of Salt Lake City and South of Salt Lake City. The thrusts to

1458-434: The Sevier orogenic belt showed that shortening directions were parallel to the thrust faulting, which was an E-W direction. Differential stress magnitudes determined from calcite twinning showed a decreasing trend exponentially toward the craton . Differential stresses causing compressional deformation in the Sevier thrust were greater than 150 MPa. The E-W contraction during the Sevier changed to roughly N-S oblique during

1512-465: The Sevier orogenic event collapsing after deactivation. Thickening of the crust due to Sevier and Laramide faulting is thought to have led to current Basin and Range extension throughout the Cenozoic. This could have caused the Charleston thrust fault to reactivate as an extensional fault. The Charleston transverse zone contained high angle faults which suggests it initiated as a response to connecting

1566-762: The Wasatch Range that appear to be relic individuals from past populations. Subspecies of big sagebrush ( Artemisia tridentata ) dominate drier portions of the landscapes. Most of the sagebrush that occurs in the Wasatch Range is mountain big sagebrush ( Artemisia tridentata ssp. vaseyana ). Many of the valley bottoms at one time were occupied by basin big sagebrush ( Artemisia tridentata ssp. tridentata ). Most of this subspecies has been removed, however, because it occurred on what constitutes prime agricultural lands. In upper elevations, and on slightly more mesic sites than that of mountain big sagebrush, one can find subalpine big sagebrush ( Artemisia tridenta ssp. spiciformis ). This subspecies occupies productive sites and often has

1620-511: The Wasatch Range, mainly in the valleys just to the west. This westside concentration is known as the Wasatch Front and has a population of well over 2 million. Salt Lake City lies between the Wasatch Range and the Great Salt Lake . The range's highest point — 11,928 feet (3,636 m) — is Mount Nebo , a triple peak rising above Nephi , at the southern end of the range. In some places

1674-602: The Wasatch, is at the southern edge of the range. The Colorado Plateau comes to its northwest corner as it meets the southern end of the Rocky Mountains. Immediately west of these two, the Great Basin , which is the northern region of the Basin and Range Province , begins and stretches westward across western Utah and Nevada until it reaches the Sierra Nevada near the Nevada/ California border. Geologic faults punctuate

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1728-595: The belt is not entirely agreed upon by researchers. However, Sevier deformation had begun by the Jurassic. Deformation in the southern portion of the Sevier fold and thrust belt began around 160 Ma. Strain was transferred eastward to the Keystone thrust by 99 Ma. In northern Utah, the Willard thrust sheet was emplaced around 120 Ma. Strain was progressively transferred to the Hogsback Thrust in western Wyoming. Faults near

1782-611: The canyons and alpine valleys of the Wasatch Range. These offer backcountry access close to a large metropolitan area. There is rock climbing and mountaineering on the towering limestone , granite , and quartzite peaks and in many of the surrounding canyons. Winter recreation includes ski touring , ski mountaineering , and snowshoeing . Alpine lakes and streams offer somewhat overworked fishing opportunities. The Wasatch Mountain Club has regular activities. The Utah Native Plant Society conducts regular walks from spring until fall along

1836-461: The city within a short distance. Dirt roads readily drivable in passenger cars with moderate clearance stretch up from Park City, Heber, and Big Cottonwood Canyon. These reach about 10,000 feet (3,000 m) above sea level and provide long-range high country views. The Wasatch Range's origins are rooted in the Sevier Orogeny . As the Farallon plate subducted under the North American plate between

1890-562: The east. In contrast, the Laramide orogeny produced “basement-cored” uplifts that often took advantage of pre-existing faults that formed during rifting in the late Precambrian during the breakup of the supercontinent Rodinia or during the Ancestral Rocky Mountains orogeny. The Sevier orogenic belt consisted of a series of thin plates along gently dipping west thrust sheets and moving from west to east. These thin skinned thrusts moved late Precambrian to Mesozoic age rock of

1944-634: The eastern and steepest edge of the rising mountains. Such conglomerates can be seen throughout Utah in Echo Canyon, the Red Narrows in Spanish Fork Canyon, and in Leamington Canyon near Delta, Utah . Today Sevier faults at the surface have been broken up and tilted steeply from their original gently dipping positions due to the extension of the Basin and Range faulting. The earliest thrusts of

1998-603: The foothills of the central Wasatch Front and in adjoining canyons as the season progresses. Many wildflowers bloom in the late summer in Albion Basin at the top of Little Cottonwood Canyon . Sevier orogeny The Sevier orogeny was a mountain-building event that affected western North America from northern Canada to the north to Mexico to the south. The Sevier orogeny was the result of convergent boundary tectonic activity, and deformation occurred from approximately 160 million years (Ma) ago to around 50 Ma. This orogeny

2052-494: The leading edge of the Sevier remained active until at least the Eocene. At this time the elevated crust ran into the Colorado Plateau . The collision resulted in lateral spreading of deformation and led to a weakened lithosphere and crustal thickening. Metamorphism due to the crustal heating and thickening is prevalent between 90 and 70 Ma in the present Great Basin region. Parallel thrust faults and folds make up

2106-407: The low angle thrust faults of the Sevier. The Charleston transverse zone outlines a main sidewall ramp that would have been part of the Sevier belt. To the north of the Uinta/Cottonwood arch during the Sevier orogeny there was a basement high area gently dipping to the north identified by isopach maps. Thus sediment thickened quickly to the south. To the north strata changed gradually throughout

2160-443: The most deformed in orogenic events, the interior of continental plates can also deform. In the Sevier-Laramide orogenic events evidence for interior plate deformation includes folds , cleavage and joint fabrics, distorted fossils , persistent faulting , and calcite twinning . The Sevier fold and thrust belt was active between late Jurassic (201 - 145 Mya) through Eocene (56 - 34 Mya) time. The actual age of initiation of

2214-711: The mountains rise steeply from the valley's base elevation of 4,330 feet (1,320 m) to over 11,000 feet (3,400 m). Other notable peaks include Mount Timpanogos , a massive peak that looms over northern Utah County and is especially prominent from Pleasant Grove and Orem ; Lone Peak , the Twin Peaks , and Mount Olympus , which overlooks the Salt Lake Valley ; Francis Peak overlooking both Morgan and Davis counties; and Ben Lomond and Mount Ogden , both towering over Ogden . Topping out below 12,000 feet (3,700 m), Wasatch peaks are not especially high compared to

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2268-470: The north are much better understood because oil and gas are often associated with them. The northern portion runs through present day Utah, Idaho, and Wyoming. The southern portion stops around Las Vegas . The total crustal shortening of the northern portion was roughly 60 miles. The Sevier belt left behind many distinctive geologic features in the Wyoming and Utah region, namely recesses and salients. Transverse zones can accompany thrust faults connecting

2322-589: The progression of the Sevier and the transition to Laramide deformation, and by the late Cretaceous volcanism related to Farallon Plate subduction could be found as far east as the Colorado Mineral Belt, east of the leading edge of the Sevier fold and thrust belt. As Sevier thrust faults were uplifted, thrust sheet erosion occurred; those eroded sediments were then deposited where accommodation space existed. Dynamic subsidence and flexure due to crustal loading created space where sediments could accumulate. As

2376-638: The range across Wasatch County transforms into the relatively flat, windswept Wasatch Plateau at an elevation of about 8,500 feet (2,600 m) to 9,500 feet (2,900 m). At its southeastern edge, just north of Helper , it runs into the Book Cliffs . Further north, the Heber Valley and Weber River Valley separate the Wasatch Range from the Uinta Mountains , while the Bear River Valley and Bear Lake Valley separate it from lower mountain ranges that mark

2430-446: The range include US-6 / US-89 through Spanish Fork Canyon , US-189 through Provo Canyon , Utah State Route 39 extending east from Huntsville (a route which is closed in winter), US‑89/ US-91 through Logan Canyon , and along Idaho State Highway 36 near the northern end of the range. The Denver and Rio Grande Western Railroad had a line through the Wasatch Range via Soldier Summit Pass and Spanish Fork Canyon. Now operated by

2484-590: The range, chief among them the Wasatch Fault . These faults also formed the Timpanogos Cave . A series of mountain valleys punctuate the northern Wasatch Range. While the western side of the range drops sharply to the floors of the Wasatch Front valleys, the eastern side of the range is gentler, allowing for the construction of several ski resorts. The Cottonwoods, a particularly rugged and dense area just east of

2538-516: The segments of the belt. One such zone is the Charleston transverse zone linking the Provo salient to the southern arm of the Uinta/Cottonwood arch. Although the Uinta/Cottonwood arch is a Laramide structure the Sevier helped the arch form. Another important zone is the Mount Raymond transverse zone connecting the Wyoming salient and the northern arm of the arch. While continental margins are typically

2592-466: The shaping of the curvature of the Uinta recess prior to uplift of the Uinta/Cottonwood arch. Focusing on the southern portion of the Sevier thrust belt many thrust faults can be found. One thrust system is known as the Garden Valley thrust system in the central Nevada thrust belt. Thrusts within this system include the Pahranagat, Mount Irish, and Golden Gate thrusts. These thrusts were correlated with

2646-511: The southward Gass Peak thrust. The Gass Peak thrust is located in the Las Vegas Range and is a Sevier age structure. This thrust may have been responsible for the largest slip of the major belt along that latitude. These thrusts were located all along the same strike. This region showed small scale extension in the Cenozoic due to reactivation of the thrusts. Such a correlation suggests that

2700-405: The thrust and a gradual curve developed around the Wyoming salient and to the south around the Provo salient. The Charleston and Mount Raymond transverse zones formed the Uinta recess indicating the recess was initiated during the Sevier orogeny. The results were interpreted to support the Charleston transverse zone forming during the Sevier orogeny to accommodate geometric changes along strike of

2754-418: The thrusts. The zone served as a linking tool of the various segments of the orogeny. The transverse zone varied throughout the region in terms of depth and displacement. The zone was later tilted and was reactivated through crustal extension. Results also support the Uinta recess forming during the Sevier orogeny due to similar geometric crustal accommodation. Displacement on Sevier aged thrust faults caused

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2808-486: The western edge of the Green River Basin. The Wasatch Range is traversed by just seven highways, along with several rugged mountain roads and unpaved trails. The most prominent are I-80 through Parley's Canyon east of Salt Lake City and I-84 through Weber Canyon southeast of Ogden. They meet near the ghost town of Echo on the eastern slopes of the range and continue northeast as I‑80. Other highways through

2862-528: The word meant "land of many waters," then posited, "the word is a common one among the Shoshones, and is given to a berry basket" carried by women. Since the earliest days of European settlement, most of Utah's population has chosen to settle along the range's western front, where numerous rivers exit the mountains. For early settlers, the mountains were a vital source of water, timber, and granite. Today, 85% of Utah's population lives within 15 miles (24 km) of

2916-434: Was caused by the subduction of the oceanic Farallon Plate underneath the continental North American Plate . Crustal thickening that led to mountain building was caused by a combination of compressive forces and conductive heating initiated by subduction, which led to deformation. The Sevier River area of central Utah is the namesake of this event. The Sevier Fold and Thrust Belt extends from southern California near

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