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Sunset Crater

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Continental climates often have a significant annual variation in temperature (warm to hot summers and cold winters). They tend to occur in central and eastern parts of the three northern-tier continents ( North America , Europe , and Asia ), typically in the middle latitudes (40 to 55 or 60 degrees north), often within large landmasses, where prevailing winds blow overland bringing some precipitation, and temperatures are not moderated by oceans. Continental climates occur mostly in the Northern Hemisphere due to the large landmasses found there. Most of northeastern China , eastern and southeastern Europe , much of Russia south of the Arctic Circle , central and southeastern Canada , and the central and northeastern United States have this type of climate. Continentality is a measure of the degree to which a region experiences this type of climate.

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27-608: Sunset Crater is a cinder cone located north of Flagstaff in the U.S. state of Arizona . The crater is within the Sunset Crater Volcano National Monument . Sunset Crater is the youngest in a string of volcanoes (the San Francisco volcanic field ) that is related to the nearby San Francisco Peaks . The date of the eruptions that formed the 340-meter-high cone (1,120 ft) was initially derived from tree-ring dates , suggesting

54-415: A Hollywood film company, Famous Players–Lasky Corporation , planned to detonate large quantities of explosives on the side of Sunset Crater in order to create an avalanche for Zane Grey 's motion picture Avalanche . Public outcry over this plan led in part to the proclamation of Sunset Crater Volcano National Monument by President Herbert Hoover in 1930. A 1-mile (1.6 km), self-guided loop trail

81-441: A lava flow around the cone's base. When the eruption ends, a symmetrical cone of cinders sits at the center of a surrounding pad of lava. If the crater is fully breached, the remaining walls form an amphitheater or horseshoe shape around the vent. Basaltic cinder cones are the most characteristic type of volcano associated with intraplate volcanism . They are particularly common in association with alkaline magmatism , in which

108-443: A volcanic vent . The pyroclastic fragments are formed by explosive eruptions or lava fountains from a single, typically cylindrical, vent. As the gas-charged lava is blown violently into the air, it breaks into small fragments that solidify and fall as either cinders, clinkers, or scoria around the vent to form a cone that often is symmetrical; with slopes between 30 and 40°; and a nearly circular ground plan. Most cinder cones have

135-433: A 10-kilometer-long fissure (6.2 mi) extending southeast produced small spatter ramparts and a 6.4-kilometer-long lava flow (4 mi) to the east. The Sunset Crater eruption peaked at VEI 4 (Sub- Plinian ), produced a total 0.52 km of ejecta, had an eruption column between 20-30km tall and produced a blanket of ash and lapilli covering an area of more than 2,100 square kilometers (810 sq mi), which forced

162-486: A bowl-shaped crater at the summit. Cinder cones range in size from tens to hundreds of meters tall. They are composed of loose pyroclastic material ( cinder or scoria ), which distinguishes them from spatter cones , which are composed of agglomerated volcanic bombs . The pyroclastic material making up a cinder cone is usually basaltic to andesitic in composition. It is often glassy and contains numerous gas bubbles "frozen" into place as magma exploded into

189-454: A group of four young cinder cones NW of Las Pilas volcano. Since its initial eruption in 1850, it has erupted more than 20 times, most recently in 1995 and 1999. Satellite images suggest that cinder cones occur on other terrestrial bodies in the solar system. On Mars, they have been reported on the flanks of Pavonis Mons in Tharsis , in the region of Hydraotes Chaos on the bottom of

216-430: A larger area. Therefore, it seems that erupted amount of material is not sufficient on Mars for the flank slopes to attain the angle of repose and Martian cinder cones seem to be ruled mainly by ballistic distribution and not by material redistribution on flanks as typical on Earth. Cinder cones often are highly symmetric, but strong prevailing winds at the time of eruption can cause a greater accumulation of cinder on

243-422: A trail leading to the crater, but a short trail at the base remains. The hiking trail below the summit skirts the substantial Bonito Lava Flow. This hardened lava is black and appears fresh as it has devastated the forest in its path. The lava flow also created an ice cave or tube that is now closed to the public after a partial collapse. On June 5, 2015, a website with satellite images reported steam rising from

270-405: Is characterized by slumping and blasts that destroy the original rim, while the fourth stage is characterized by the buildup of talus beyond the zone where cinder falls to the surface (the ballistic zone ). During the waning stage of a cinder cone eruption, the magma has lost most of its gas content. This gas-depleted magma does not fountain but oozes quietly into the crater or beneath the base of

297-472: Is located at the base of Sunset Crater, but hiking to the summit is not permitted. A trail providing access to the summit and crater was closed in 1973 because of excessive erosion caused by hikers. A visitor center is located near the park entrance, 15 miles (24 km) north of Flagstaff, Arizona , along U.S. Highway 89 . In April 2022, the Tunnel Fire burned over the entirety of the monument, though

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324-697: Is somewhat more stable than winter weather. Continental climates are considered as temperate climate varieties due to their location in the temperate zones, but are classified separately from other temperate climates in the Köppen climate classification system where they are identified by their first letter, a capital D . In the Trewartha climate classification , they are identified as Dc . Continental climate has at least one month averaging below 0 °C (32 °F) and at least one month averaging above 10 °C (50 °F). Annual precipitation in this zone

351-669: Is usually between 600 millimetres (24 in) and 1,200 millimetres (47 in), The timing of intermediate spring-like or autumn-like temperatures in this zone vary depending on latitude and/or elevation. For example, spring may arrive as soon as March (in Northern hemisphere , September in Southern hemisphere ) in the southern (in Northern hemisphere, northern in Southern hemisphere), parts of this zone or as late as May (November) in

378-728: The Coprates Chasma , or in the volcanic field Ulysses Colles . It is also suggested that domical structures in Marius Hills (on the Moon) might represent lunar cinder cones. The size and shape of cinder cones depend on environmental properties as different gravity and/or atmospheric pressure might change the dispersion of ejected scoria particles. For example, cinder cones on Mars seem to be more than two times wider than terrestrial analogues as lower atmospheric pressure and gravity enable wider dispersion of ejected particles over

405-412: The air and then cooled quickly. Lava fragments larger than 64 mm across, known as volcanic bombs , are also a common product of cinder cone eruptions. The growth of a cinder cone may be divided into four stages. In the first stage, a low-rimmed scoria ring forms around the erupting event. During the second stage, the rim is built up and a talus slope begins to form outside the rim. The third stage

432-473: The cone as lava. Lava rarely issues from the top (except as a fountain) because the loose, uncemented cinders are too weak to support the pressure exerted by molten rock as it rises toward the surface through the central vent. Because it contains so few gas bubbles, the molten lava is denser than the bubble-rich cinders. Thus, it often burrows out along the bottom of the cinder cone, lifting the less dense cinders like corks on water, and advances outward, creating

459-616: The crater, leading to fears that Sunset Crater was erupting. The cause of the steam was later determined to be a forest fire, and geologists stated that the volcano was extinct. Sunset Crater Volcano National Monument is a U.S. national monument created to protect Sunset Crater, a cinder cone within the San Francisco Volcanic Field. The monument is managed by the National Park Service in conjunction with nearby Wupatki National Monument . In 1928,

486-823: The downwind side of the vent. Some cinder cones are monogenetic , forming from a single short eruptive episode that produces a very small volume of lava. The eruption typically last just weeks or months, but can occasionally last fifteen years or longer. Parícutin in Mexico, Diamond Head , Koko Head , Punchbowl Crater , Mt Le Brun from the Coalstoun Lakes volcanic field , and some cinder cones on Mauna Kea are monogenetic cinder cones. However, not all cinder cones are monogenetic, with some ancient cinder cones showing intervals of soil formation between flows that indicate that eruptions were separated by thousands to tens of thousands of years. Monogenetic cones likely form when

513-589: The erupted lava is enriched in sodium and potassium oxides . Cinder cones are also commonly found on the flanks of shield volcanoes , stratovolcanoes , and calderas . For example, geologists have identified nearly 100 cinder cones on the flanks of Mauna Kea , a shield volcano located on the island of Hawaii . Such cinder cones likely represent the final stages of activity of a mafic volcano. However, most volcanic cones formed in Hawaiian-type eruptions are spatter cones rather than cinder cones, due to

540-456: The eruption began between the growing seasons of AD 1064–1065. However, more recent geologic and archaeological evidence places the eruption around AD 1085. The largest vent of the eruption, Sunset Crater itself, was the source of the Bonito and Kana-a lava flows that extended about 2.5 kilometers (1.6 mi) northwest and 9.6 kilometers (6 mi) northeast, respectively. Additional vents along

567-510: The fluid nature of the lava. The most famous cinder cone, Paricutin , grew out of a corn field in Mexico in 1943 from a new vent. Eruptions continued for nine years, built the cone to a height of 424 meters (1,391 ft), and produced lava flows that covered 25 km (9.7 sq mi). The Earth's most historically active cinder cone is Cerro Negro in Nicaragua. It is part of

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594-472: The north (south). Summers are warm or hot while winters are below freezing and sustain lots of frost. Continental climates exist where cold air masses infiltrate during the winter from shorter days and warm air masses form in summer under conditions of high sun and longer days. Places with continental climates are as a rule either far from any moderating effect of oceans or are so situated that prevailing winds tend to head offshore. Such regions get quite warm in

621-470: The rate of magma supply to a volcanic field is very low and the eruptions are spread out in space and time. This prevents any one eruption from establishing a system of " plumbing " that would provide an easy path to the surface for subsequent eruptions. Thus each eruption must find its independent path to the surface. Continental climate#Continental climate In continental climates, precipitation tends to be moderate in amount, concentrated mostly in

648-569: The summer, achieving temperatures characteristic of tropical climates but are colder than any other climates of similar latitude in the winter. In the Köppen climate system, these climates grade off toward temperate climates equator-ward where winters are less severe and semi-arid climates or arid climates where precipitation becomes inadequate for tall-grass prairies and shrublands. In Europe these climates may grade off into oceanic climates ( Cfb ) or subpolar oceanic climates ( Cfc ) in which

675-566: The temporary abandonment of settlements of the local Sinagua people. The volcano has partially revegetated, with pines and wildflowers . The crater is the namesake for the Sunset Crater Beardtongue ( Penstemon clutei ). The volcano is monitored by the Yellowstone Volcano Observatory and is classified as a moderate threat. Damage from hikers forced the National Park Service to close

702-611: The visitor center was spared. In December 2022, 98 acres including the visitor center and administrative facilities were transferred from Coconino National Forest to the national monument. According to the Köppen Climate Classification system, Sunset Crater has a Continental climate , abbreviated "Dsb" on climate maps. Cinder cone A cinder cone (or scoria cone ) is a steep conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around

729-580: The warmer months. Only a few areas—in the mountains of the Pacific Northwest of North America and in Iran , northern Iraq , adjacent Turkey , Afghanistan , Pakistan , and Central Asia —show a winter maximum in precipitation. A portion of the annual precipitation falls as snowfall, and snow often remains on the ground for more than a month. Summers in continental climates can feature thunderstorms and frequent hot temperatures; however, summer weather

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