Craters of the Moon National Monument and Preserve
The Craters of the Moon National Monument ( since 2000 also Craters of the Moon National Monument and Preserve ) is a sanctuary from the type of National Monuments in the center of the plain of the Snake River in the U.S. state of Idaho. Approximately 1750 meters above sea The area consists of large lava flows and some cinder cones. The volcanic activity at rest, but is not extinguished. The last eruption in the crater -of-the -Moon - area is about 2000 years back.
The Craters of the Moon are in one of the remotest regions of the United States in the early 20th century were first explored in more detail and provided in 1924 under protection. Previously, several times slightly extended, the area was extended in 2000 to 13 times the area. Since then stand the whole volcanic field, including the Wapi field in the south and the adjacent prairie areas under protection. The expansion areas subject to less protection status of a National Preserve, which is why hunting is still permitted and remain the existing agreements for the use of public land by private herds cattle ranchers in force. The reserve is managed jointly by the National Park Service and the Bureau of Land Management, two authorities under the auspices of the U.S. Department of the Interior.
The name of the protected area is from the hostile impression that early visitors had. As part of the Apollo program astronauts used the area for a short time for training.
Geology
The Craters of the Moon area is located in the center of the volcanic embossed level of the Snake River, which runs through the southern Idaho. Like the entire level, it falls easily and evenly to the south. Today's landscape and its geological subsoil were minted in three characteristic phases.
Yellowstone hotspot
The surface of the plane are rhyolitic tuff and rocks from compressed volcanic ash. They were created by a hotspot, which was fed by a plume of magma from the mantle. About this plume shifts the North American Plate, one of the tectonic plates of the earth's crust, so that the volcanic activity apparently moves from southwest to northeast. The hotspot is now under the Yellowstone National Park and is responsible for the volcanic activity of the Yellowstone super volcano, its caldera, the geysers and other volcanic manifestations of the national park responsible.
The present sanctuary was located in front of around 11 million years above the hotspot. The ascending from the mantle magma melted granitic rocks of the earth's crust. Here, the surface buckled on. With a further increase of the energy it came to the catastrophic eruption and the molten granite was ejected in the form of rhyolite. It emerged a caldera and extensive tuff and ash layers. With the apparent hike there was a shift of the location of the next eruption. For the Snake River Plain 142 massive eruptions are detected, plus hundreds of medium and small. The calderas typically overlap. In this way, rhyolitic lava and ash were ejected, which today characterize the deep underground of the Snake River Plain. In the Earth's crust, at a depth of at least 10 km, the melting processes of the hotspot, leaving a 10-15 km thick layer of basaltic scoria, which is largely in the molten state until today. Since it provides the energy for the volcanic activity in the region. The surface was decreased after cooling, there was a setting that marks the migration route of the North American plate over the hotspot away: the lowlands of the Snake River Plain.
Basaltic eruptions
Prior to about six million years ago in western North America, a tectonic process that led to an expansion of the earth's crust, which had a variety largely parallel, roughly extending in a north-south direction grave breaches result. At that time, the Basin -and- Range region emerged with their parallel trench and Horst structures that currently ranges from Mexico in the south to the north even to Idaho. In the south of present-day Idaho, the forces acted on the sunken layers of eruptive rocks on the migration route of the hotspot. Here, the stretching of the crust led to a variety of stretch breaks in a northwest-southeast orientation. The largest of the parallel strain fractures located in the center of the plane has a length of about 80 km at about 2.5 km wide and is called the Great Rift ( of Idaho ). According to other interpretations of the Great Rift was under pressure from rising lava from the reservoir, which was plastically deformed by stress from above and thereby generated cracks.
In the Great Rift, as in the other breaks in the Snake River Plain, basaltic magma rose in Dykes and stepped out in the form of columns volcanoes, cinder cones and flat shield volcanoes at the surface. During the period of around 6 million years ago until about 15,000 years mighty lava flows that formed several up to 1200 m thick layers in the center of the Snake River Plain, in the isolated layers are embedded in sedimentary rock formed. They cover about 95% of the layer.
Recent activity
The date last phase of volcanic activity in the Crater of the Moon area began about 15,000 years ago. At the Great Rift were three further fractures and five other young lava fields. The three fields of the Great Rift, Craters of the Moon, Kings Bowl, and Wapi are within the reserve. It is named after the Craters of the Moon - field, which is the largest lava field in the Snake River Plain and at the same time in the Continental United States, which originates predominantly from the Holocene, ie the last 10,000 years. It is composed of 60 individual lava, which overlap each other. Around 30 km ³ basaltic lava occurred in eight eruptive periods and cover a composite area of approximately 1600 km ².
About 80 % of the lava fields consist of the low viscous pahoehoe lava. In hardened form it is characterized by smooth surfaces and round shapes, which can take a blue or green gloss isolated. It is fed by long rivers, which can leave hollow lava tubes during deceleration and cooling, elongated in caves and among the lava flows. Five lava tubes can be committed in the territory. The rest of the lava fields makes the irregular Aa lava. She has a sharp-edged surface, which is composed of individual chunks of less than one to a few centimeters in size. Her figure is partly undulating with up to 3 m high mountain and Talstrukturen. Their boundaries are usually marked by a steep front.
Geochemical consist of basaltic lava flows in the Craters of the Moon - field olivinischem Tholeiit. They are particularly rich in iron, phosphorus, titanium and alkali metals
When the eruptions around 25 cinder cones were out of the lava flows raised, often caused by several obvious vents, so that overlap the cone or completely inside another. In addition, volcanic bombs of various types and sizes were ejected. The flowing lava formed several flat shield volcanoes, including the Wapi field, which is the result of only one eruption.
The recent manifestations are smaller lava flows in the north of the Craters of the Moon field. Underneath is the North Crater flow, which has been dated to an age of about 2000 years. Although the volcanic activity in the Craters of the Moon area since then rests, it has not been extinguished.
Ecosystems
The area of the Craters of the Moon is in the range of the Eastern Snake River Basalt level. The climate is semi-arid, continental with hot, dry summers and cold winters. The soils are young. if available, the humus layer is low. A distinction must be three soil types: the young lava fields, areas of older lava flows, which already has been a bottoming out as well as soils on eolian, verfrachteten by wind sediments of sand and loess. Specific to the reserve - and not typical for the region - is the small-scale mosaic of habitats. Several hundred Kipukas, medium and small islands of weathered soils are incorporated into younger lava flows, and each form completed ecosystems.
The young lava are mostly without any vegetation. Chance are tufts of spring grasses. In cracks and crevices grow various kinds, endure the extreme drought. Below are the Penstemon Penstemon species deustus that Phlox Phlox hoodii, the blocking herb greenhouse Aliciella leptomeria finger and herbs. On the volcanic cones and some hillsides there are local enough water for montane scrub and forest communities. Here junipers, the American Aspen Tree and the Nevada pineal pine ( Pinus flexilis ).
On weathered lava fields, the typical plant community is a sagebrush - steppe. The eponymous Sagebrush forms a large area low bushes, otherwise the soil is loose with the prairie grasses covered. The most common type of grass is blue Tufts wheatgrass ( Agropyron spicatum - also: Pseudoroegnaria spicata ), which grows in clumps. In addition, ( Oryzopsis hymenoides ) different spring grasses and Indian rice grass occur. Purshia tridentata is a common shrub. The downy brome occurs as a neophyte.
The same plant communities cover the floors outside the lava fields. The vegetation is denser, so the land for extensive grazing with cattle serve. The plains in the center and south of the area are highly disturbed by historic and persistent grazing.
The fauna is characterized by the severe drought and extreme summer temperatures. Various animals adapt by a nocturnal lifestyle. These include pocket gophers, skunk, red fox, bobcat, cougar, several species of bats, nightjars, owls and most small rodents. The off-peak use mule deer, coyote, porcupine and cottontail rabbits, and many songbirds. Days are active ground squirrels, chipmunks, marmots, as well as lizards, snakes, eagles and buzzards. In the lava tubes, some beetle species that are endemic to the area to live.
History
Originally the Snake River Plain was sparsely inhabited by Shoshone. The lava and other volcanic structures of the Great Rift, however, were hostile and were not used permanently. At a lava tube, which is now called the Indian Tunnel, stones were arranged artificially to the tunnel opening.
The Lewis and Clark Expedition of 1805/6 brought the first white men to present-day Idaho, they passed the area but north of the present-day reserve. In the 1830s the Snake River area was visited by trappers and fur traders of the British Hudson 's Bay Company. Also, they never came home in today's reserve. 1833 explored the U.S. officer Benjamin Bonneville the Snake River and parts of the plane. The first recorded visit of a white man in today's reserve was held in 1852. John Jeffrey explored a northern abbreviation for the settlers treks on the Oregon Trail, to circumvent the wide loops of the Snake River. His route led through the extreme northwest of today's National Monuments. It was used only sporadically in the first years, but gained importance in 1862 when Shoshone Bannock Indians themselves and fought on the main route on the Snake River against the invading whites in their country. In order to escape the Indians, the largest Siedlerzug on the Oregon Trail all time with 338 cars and 1095 people by Tim Goodale was passed over the northern route, which was from then on known as Goodale Cutoff and preferred.
1901, the first ascent of the area by a geologist of the U.S. Geological Survey took place. Harold Stearns, the USGS geologist visited the area in 1921 and 1923 and wrote a first report, which was published in 1924 in the Geographical Review. The National Park Service invited him to a report which should include the area of structures and appropriate limits of a possible National Monuments. 1920, Robert W. Limbert and his neighbor WL Cole, natural history, enthusiastic lay people from Boise, hiked in 17 days by the Great Rift area. They explored the region as the first full-length and described the various volcanic structures. Limbert published in 1924 a report on the expedition in the popular National Geographic Magazine under the title "Among the, Craters of the Moon. '" He suggested to designate the site as a National Park, and sent his sketch book with photos and other notes to President Calvin Coolidge. The basis of this report for the National Park Service and the public awareness of the area after the publication of the National Geographic article used Coolidge the authorization of the Antiquity Act and dedicated the area as a National Monument.
In the first decades of the reserve was only slightly expanded. In preparation for the 50th anniversary of the National Park Service mid-1950s, the Mission 66 program was launched, was invested with the approximately one billion dollars in the national parks and other protected areas of the Federation. Also Craters of the Moon was in 1956 a new visitor center, a campground, a circle through the reserve led street and other facilities for natural and cultural interpretation and visitor services.
1969 team explored the Apollo program geologically special regions in the western United States. The astronauts Alan Shepard, Edgar Mitchell, Eugene Cernan and Joe Engle were among others in the Crater of the Moon area and learned the expert identification and description of volcanic rock, as was to be expected on the moon.
1970 devoted to the Congress of the United States the majority of National Monuments in addition as Wilderness Area, the most severe class of protected natural areas in the United States. It was the first officially protected wilderness in an area of the National Park Service.
In the 1980s, operated local tourism entrepreneurs and the policy of the State Idaho the rededication of the national monument to a national park. They expected it a stronger attraction for the region's tourism. Idaho has the only state in the Western United States, no national park if one disregards within its borders, by a narrow strip at the edge of Yellowstone National Park. The National Park Service rejected the appreciation: The area would therefore not suitable with the volcanism only one type of natural forms and would be a national park. Its status as a National Monument would be appropriate. Early 1990s was a mediating position developed, after which it should stay with the designation as a National Monument, but the area could be extended spacious.
In 2000, the reserve for the entire lava fields of the Great Rift area was extended, also incorporating neighboring prairie areas under the administration of the Bureau of Land Management. The protected area under the name Crater of the Moon National Monument and Preserve now includes almost 2900 km ² and all volcanic phenomena in the region.
The reserve today
The undeveloped area of the Craters of the Moon National Monument and Preserve is located in the northern part of the total area on U.S. Highway US-20, which runs here bundled with U.S. 26 and U.S. 93. From Highway branches off a side road from the visitor center, it continues to the small campsite and a one-way street as shown, about 11 km long loop that runs through the north of the main lava field. The Autoroute winds around several volcanic cones, of their turn branch off from access roads that lead to designated short hiking trails.
Committed are most of the North Crater Flow Trail at the visitor center, which introduces the characteristics of a lava landscape, the Devils Orchard Trail to explore the slow colonization of the lava landscape with pioneer vegetation on the visitors and the Caves trail to the inputs of four accessible for visitors and performs a viewable lava tubes. The Indian tunnel can be committed in the full length of nearly 250 m without additional equipment, other equipment requiring cave with several independent light sources and the willingness to crawl through narrow entrances. There are also two designated trails that lead from the developed part of the area in the wilderness region. In the summer season daily guided walks and talks by the rangers are offered. In winter, the loop road is closed to traffic and opened as a cross-country ski trail. Guided tours on snowshoes will take place on the weekends.
Craters of the Moon National Monument and Preserve is well over 200,000 visitors a year, the most important tourist destination in the sparsely populated region. However, it is typically only a side trip for visitors of other targets in the broader community and will be used to select only around 20 % of the visitors. The others come for another reason to Idaho or traverse the region and only use the reserve as stopover.
Almost all visitors are limited to the developed area in the north, which accounts for only the smallest part of the conservation area. It is located in the original National Monument, which has an area of about 216 km ². Since the expansion in 2000, the area extends south to almost the entire width of the Snake River Plain. At that time, approximately 1600 km ² came under the administration of the National Park Service added as a National Preserve. This is almost exclusively of lava fields. More about 1000 km ² are under the administration of the Bureau of Land Management and in 2000 were also added to the reserve. You are steppe and the existing grazing by cattle ranchers private was retained in the designation of protected areas. In the hinterland there are a few dirt roads and slopes in the steppe shares on the lava fields you can move only on foot.