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44-641: Downstream of the confluence of Quartz Creek, the Lewis River plunges over four large waterfalls. Curly Creek, another tributary, is the only cataract in Washington with an intact natural stone bridge , and the early formation of a second natural bridge can be observed. Although the Dark Divide is largely composed of black basalt , features such as 5,238-foot (1,596 m) Dark Mountain, Dark Creek and Dark Meadows are actually named for John Dark,

88-523: A cold semi-arid climate ( BSk ). Humans have occupied the region since the last ice age 10,000 years ago. Fremont people and Ancestral Puebloans lived in the area until about 700 years ago. Spanish missionaries encountered Ute and Paiute tribes in the area when they first came through in 1775, but the first European-Americans to attempt settlement in the area were the Mormon Elk Mountain Mission in 1855, who soon abandoned

132-891: A cove . Weather-eroded arches begin their formation as deep cracks which penetrate into a sandstone layer. Erosion occurring within the cracks wears away exposed rock layers and enlarges the surface cracks isolating narrow sandstone walls which are called fins. Alternating frosts and thawing cause crumbling and flaking of the porous sandstone and eventually cut through some of the fins. The resulting holes become enlarged to arch proportions by rockfalls and weathering. The arches eventually collapse leaving only buttresses that in time will erode. Many weather-eroded arches are found in Arches National Park , Canyonlands National Park , and Grand Staircase–Escalante National Monument (GSENM), all located in southern Utah, United States. Some natural bridges may look like arches, but they form in

176-575: A 19th-century gold prospector and speculator. 46°19′06″N 121°45′39″W  /  46.31833°N 121.76083°W  / 46.31833; -121.76083 This article about a location in the state of Washington is a stub . You can help Misplaced Pages by expanding it . Natural bridge A natural arch , natural bridge , or (less commonly) rock arch is a natural landform where an arch has formed with an opening underneath. Natural arches commonly form where inland cliffs , coastal cliffs , fins or stacks are subject to erosion from

220-585: A bridge as a subtype of arch that is primarily water-formed. By contrast, the Dictionary of Geological Terms defines a natural bridge as a "natural arch that spans a valley of erosion." The largest natural arch, by a significant margin, is the Xianren Bridge in China, with a span of 122 ± 5 meters (400 ± 15 ft). On coasts two different types of arches can form depending on

264-747: A cave erosion arch made of limestone, is in Carter Caves State Resort Park and has a paved road on top. The second, a weather-eroded sandstone arch with a dirt road on top, is on the edge of Natural Bridge State Park in Kentucky. The latter arch is called White's Branch Arch (also known as the Narrows) and the road going over it is usually referred to as the Narrows Road. In Europe, the Romanian village of Ponoarele has

308-584: A presidential proclamation creating the Arches National Monument, consisting of two comparatively small, disconnected sections. The purpose of the reservation under the 1906 Antiquities Act was to protect the arches, spires, balanced rocks, and other sandstone formations for their scientific and educational value. The name Arches was suggested by Frank Pinkely, superintendent of the Park Service's southwestern national monuments, following

352-634: A proclamation substantially enlarging the Arches. Two years later, President Richard Nixon signed legislation enacted by Congress , which significantly reduced the total area enclosed, but changed its status. Arches National Park was formally dedicated in May 1972. In 1980, vandals attempted to use an abrasive kitchen cleanser to deface ancient petroglyphs in the park, prompting park officials to recruit physicist John F. Asmus , who specialized in using lasers to restore works of art, to use his technology to repair

396-466: A road segment called God's Bridge that is 30 m (98 ft) long and 13 m (43 ft) wide, passing over a stone arch 22 m (72 ft) high and 9 m (30 ft) thick. The railroad from Lima , Peru crosses the Rio Yauli on a natural bridge near kilometer 214.2 as it approaches the city of La Oroya . Arches National Park Arches National Park is a national park of

440-560: A span of 225 feet (69 m). The Rainbow Bridge National Monument 's namesake was also formed by flowing water which created the largest known natural bridge in the Western Hemisphere with a span of 234 feet (71 m), based on a laser measurement made in 2007. Xianren Bridge , also known as Fairy Bridge, in Guangxi , China is currently the world's largest known natural bridge with a span recorded at 400 feet (120 m) by

484-571: A vertical pothole formation meets a horizontal cave , causing a union into a long arch structure. The erosion process within Arches National Park will continue as time continues to pass. Continued erosion combined with vertical and horizontal stress will eventually cause arches to collapse, but still, new arches will continue to form for thousands of years. According to the Köppen climate classification system, Arches Visitor Center has

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528-478: A visit to the Windows section in 1925. In late 1938, President Franklin D. Roosevelt signed a proclamation that enlarged the Arches to protect additional scenic features and permit the development of facilities to promote tourism. A small adjustment was made by President Dwight Eisenhower in 1960 to accommodate a new road alignment. In early 1969, just before leaving office, President Lyndon B. Johnson signed

572-510: Is also popular in the park due to its dark skies, despite the increasing light pollution from towns such as Moab. Delicate Arch is the subject of the third 2014 quarter of the U.S. Mint's America the Beautiful Quarters program commemorating national parks and historic sites. The Arches quarter had the highest production of the five 2014 national park quarters, with more than 465 million minted. American writer Edward Abbey

616-427: Is banned by park regulations. Climbing on other features in the park is allowed but regulated; in addition, slacklining and BASE jumping are banned parkwide. Climbing on named arches within the park had long been banned by park regulations, but following Dean Potter 's successful free climb on Delicate Arch in May 2006, the wording of the regulations was deemed unenforceable by the park attorney . In response,

660-599: Is required to visit the park between the hours of 7 a.m. and 4 p.m. As stated in the foundation document in U.S. National Park Service website: The purpose of Arches National Park is to protect extraordinary examples of geologic features including arches, natural bridges, windows, spires, and balanced rocks, as well as other features of geologic, historic, and scientific interest, and to provide opportunities to experience these resources and their associated values in their majestic natural settings. The national park lies above an underground evaporite layer or salt bed, which

704-486: Is the main cause of the formation of the arches, spires, balanced rocks, sandstone fins , and eroded monoliths in the area. The park consists of 310.31 km (76,680 acres; 119.81 sq mi; 31,031 ha) of high desert located on the Colorado Plateau . The highest elevation in the park is 5,653 ft (1,723 m) at Elephant Butte , and the lowest elevation is 4,085 ft (1,245 m) at

748-474: Is the main cause of the formation of the arches, spires, balanced rocks, sandstone fins , and eroded monoliths in the area. This salt bed is thousands of feet thick in places and was deposited in the Paradox Basin of the Colorado Plateau some 300 million years ago (Mya) when a sea flowed into the region and eventually evaporated. Over millions of years, the salt bed was covered with debris eroded from

792-565: The Natural Arch and Bridge Society in October 2010, with a precision of ±15 feet (4.6 m). Natural bridges can form from natural limestone caves , where paired sinkholes collapse and a ridge of stone is left standing in between, with the cave passageway connecting from sinkhole to sinkhole. Like all rock formations, natural bridges are subject to continued erosion, and will eventually collapse and disappear. One example of this

836-671: The Uncompahgre Uplift to the northeast. During the Early Jurassic (about 200 Mya), desert conditions prevailed in the region and the vast Navajo Sandstone was deposited. An additional sequence of stream laid and windblown sediments, the Entrada Sandstone (about 140 Mya), was deposited on top of the Navajo. Over 5,000 feet (1,500 m) of younger sediments were deposited and have been mostly eroded. Remnants of

880-521: The rock formations have weaker layers of rock on bottom that are holding stronger layers on top. The weaker layers would dissolve first, creating openings in the rock. Gravity caused pieces of the stronger rock layer to fall piece by piece into an arch shape. Arches form within rock fins at points of intense fracturing localization, or weak points in the rock's formation, caused by horizontal and vertical discontinuities. Lastly, water, wind, and time continued this erosion process and ultimately created

924-592: The United States in eastern Utah . The park is adjacent to the Colorado River , 4 mi (6 km) north of Moab, Utah . The park contains more than 2,000 natural sandstone arches , including the well-known Delicate Arch , which constitute the highest density of natural arches in the world. It also contains a variety of other unique geological resources and formations. The national park lies above an underground evaporite layer or salt bed, which

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968-455: The arches form, and the buff-colored Navajo Sandstone. These are visible in layer-cake fashion throughout most of the park. Over time, water seeped into the surface cracks, joints, and folds of these layers. Ice formed in the fissures, expanding and putting pressure on surrounding rock, breaking off bits and pieces. Winds later cleaned out the loose particles. A series of free-standing fins remained. Wind and water attacked these fins until, in some,

1012-507: The arches of Arches National Park. All of the arches in the park are made of Entrada Sandstone, however, there are slight differences in how each arch was developed. Entrada Sandstone is categorized into three groups: Slick rock members , Dewey rock members, and Moab members . Vertical arches can be developed from Slick rock members, a combination of Slick rock members and Moab members, or Slick rock members resting above Dewey rock members. Horizontal arches (also called potholes) are formed when

1056-425: The area be made a national monument. The following year, additional support for the monument idea came from Laurence Gould , a University of Michigan graduate student (and future polar explorer) studying the geology of the nearby La Sal Mountains , who was shown the scenic area by local physician Dr. J. W. "Doc" Williams. A succession of government investigators examined the area, in part due to confusion as to

1100-727: The area in September 1923 at the invitation of Alexander Ringhoffer, a Hungarian -born prospector living in Salt Valley. Ringhoffer had written to the railroad to interest them in the tourist potential of a scenic area he had discovered the previous year with his two sons and a son-in-law, which he called the Devils Garden (known today as the Klondike Bluffs). Wadleigh was impressed by what Ringhoffer showed him, and suggested to Park Service director Stephen T. Mather that

1144-614: The area. Ranchers, farmers, and prospectors later settled Moab in the neighboring Riverine Valley in the late 1870s. Word of the beauty of the surrounding rock formations spread beyond the settlement as a possible tourist destination. The Arches area was first brought to the attention of the National Park Service by Frank A. Wadleigh, passenger traffic manager of the Denver and Rio Grande Western Railroad . Wadleigh, accompanied by railroad photographer George L. Beam, visited

1188-501: The areas between the domes. In some places, they turned almost on edge. The result of one such 2,500 ft (760 m) displacement, the Moab Fault , is seen from the visitor center. As this subsurface movement of salt shaped the landscape, erosion removed the younger rock layers from the surface. Except for isolated remnants, the major formations visible in the park today are the salmon-colored Entrada Sandstone, in which most of

1232-414: The cementing material gave way and chunks of rock tumbled out. Many damaged fins collapsed. Others, with the right degree of hardness and balance, survived despite their missing sections. These became the famous arches. Although the park's terrain may appear rugged and durable, it is extremely fragile. More than 1 million visitors each year threaten the fragile high-desert ecosystem. The problem lies within

1276-465: The coastline, with weak rock such as shale protected by stronger rock such as limestone . The wave action along concordant coastlines breaks through the strong rock and then erodes the weak rock very quickly. Good examples of this type of arch are the Durdle Door and Stair Hole near Lulworth Cove on Dorset 's Jurassic Coast in south England. When Stair Hole eventually collapses it will form

1320-562: The cover exist in the area including exposures of the Cretaceous Mancos Shale . The arches of the area are developed mostly within the Entrada formation. The weight of this cover caused the salt bed below it to liquefy and thrust up layers of rock into salt domes . The evaporites of the area formed more unusual "salt anticlines " or linear regions of uplift. Faulting occurred and whole sections of rock subsided into

1364-468: The damage. Asmus "zapped the panel with intense light pulses and succeeded in removing most of the cleanser". In 2016, there was another vandalism event on Frame Arch in the park, where a section of the rock was carved out. Due to advances in technology, in 2018 the arch was repaired through color match and modern infilling methods. Climbing Balanced Rock or any named or unnamed arch in Arches National Park with an opening larger than 3 ft (0.9 m)

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1408-404: The edge of the salt bed continued to erode and shift into vertical sandstone walls called fins . Sand collected between vertical walls of the fins, then slightly acidic rain combined with carbon dioxide in the air allowed for the chemical formation of carbonic acid within the trapped sand. Over time, the carbonic acid dissolved the calcium carbonate that held the sandstone together. Many of

1452-459: The formation eventually meeting underneath the harder caprock layer, thus creating an arch. The erosional processes exploit weaknesses in the softer rock layers making cracks larger and removing material more quickly than the caprock; however, the caprock itself continues to erode after an arch has formed, which will ultimately lead to collapse. The choice between bridge and arch is somewhat arbitrary. The Natural Arch and Bridge Society identifies

1496-573: The geology. On discordant coastlines rock types run at 90° to the coast. Wave refraction concentrates the wave energy on the headland, and an arch forms when caves break through the headland. Two examples of this type of arch are London Bridge in Victoria , Australia, and Neill Island in the Andaman Islands , India. When these arches eventually collapse, they form stacks and stumps. On concordant coastlines rock types run parallel to

1540-417: The park revised its regulations later that month, eventually imposing the current ban on arch climbing in 2014. Approved recreational activities include auto touring, hiking, bicycling, camping at the Devils Garden campground, backpacking, canyoneering , and rock climbing, with permits required for the last three activities. Guided commercial tours and ranger programs are also available. Astronomy

1584-781: The park. An abundance of wildlife occurs in Arches National Park, including spadefoot toads , antelope squirrels , scrub jays , peregrine falcons , many kinds of sparrows , red foxes , desert bighorn sheep , kangaroo rats , mule deers , cougars , midget faded rattlesnakes , yucca moths , western rattlesnakes , and collared lizards . A number of plant species are common in the park, including prickly pear cactus , Indian ricegrass , bunch grasses , cheatgrass , moss , liverworts , Utah juniper , Mormon tea , blackbrush , cliffrose , four-winged saltbrush , pinyon pine , evening primrose , sand verbena , yucca , and sacred datura . Biological soil crust consisting of cyanobacteria , lichen, mosses, green algae , and microfungi

1628-458: The path of streams that wear away and penetrate the rock. Pothole arches form by chemical weathering as water collects in natural depressions and eventually cuts through to the layer below. Natural Bridges National Monument in Utah protects the area surrounding three large natural bridges, all of which were formed by streams running through canyons, the largest of which is named Sipapu Bridge with

1672-672: The precise location. In the process, the name Devils Garden was transposed to an area on the opposite side of Salt Valley that includes Landscape Arch , the longest arch in the park. Ringhoffer's original discovery was omitted, while another area nearby, known locally as the Windows, was included. Designation of the area as a national monument was supported by the Park Service in 1926 but was resisted by President Calvin Coolidge 's Interior Secretary, Hubert Work . Finally, in April 1929, shortly after his inauguration, President Herbert Hoover signed

1716-483: The sea, rivers or weathering ( subaerial processes). Most natural arches are formed from narrow fins and sea stacks composed of sandstone or limestone with steep, often vertical, cliff faces. The formations become narrower due to erosion over geologic time scales . The softer rock stratum erodes away creating rock shelters , or alcoves, on opposite sides of the formation beneath the relatively harder stratum, or caprock , above it. The alcoves erode further into

1760-500: The soil are cytophobic soil crust index, measuring of water infiltration, and t-tests that are used to compare the values from the undisturbed and disturbed areas. Geological processes that occurred over 300 million years ago caused a salt bed to be deposited, which today lies beneath the landscape of Arches National Park. Over time, the salt bed was covered with sediments that eventually compressed into rock layers that have since been named Entrada Sandstone . Rock layers surrounding

1804-466: The soil's crust, which is composed of cyanobacteria , algae, fungi, and lichens that grow in the dusty parts of the park. Factors that make Arches National Park sensitive to visitor damage include being a semiarid region, the scarce, unpredictable rainfall, lack of deep freezing, and lack of plant litter, which results in soils that have both a low resistance to and slow recovery from, compressional forces such as foot traffic. Methods of indicating effects on

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1848-475: The visitor center. The park receives an average of less than 10 in (250 mm) of rain annually. Administered by the National Park Service , the area was originally named a national monument on April 12, 1929, and was redesignated as a national park on November 12, 1971. The park received more than 1.8 million visitors in 2021. From April 1 through October 31, a timed entry reservation

1892-626: Was a park ranger at Arches National Monument in 1956 and 1957, where he kept journals that became his book Desert Solitaire . The success of Abbey's book, as well as interest in adventure travel , has drawn many hikers , mountain bikers , and off-pavement driving enthusiasts to the area. Permitted activities within the park include camping, hiking along designated trails, backpacking, canyoneering, rock climbing, bicycling, and driving along existing roads, both paved and unpaved. The Hayduke Trail , an 812 mi (1,307 km) backpacking route named after one of Edward Abbey's characters , begins in

1936-642: Was the double-arched Victorian coastal rock formation, London Bridge , which lost an arch after storms increased erosion. Moon Hill in Yangshuo , Guizhou Province , China, is an example of an arch formed by the remnant of a karst limestone cave. In a few places in the world, natural arches are utilized by humans as transportation bridges with highways or railroads running across them. In Virginia, US Route 11 traverses Natural Bridge . Two additional natural arch roadways are found in Kentucky . The first,

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