|
Pisgah Crater
Pisgah Crater, or Pisgah Volcano, is a young volcano, volcanic cinder cone rising above a lava plain in the Mojave Desert, between Barstow, California, Barstow and Needles, California in San Bernardino County, California. The volcanic peak is around south of historic U.S. Route 66 in California, U.S. Route 66-National Old Trails Highway and of Interstate 40 in California, Interstate 40, and west of the town of Ludlow, California, Ludlow. The volcano had a historic elevation of , but has been reduced to due to mining. History The volcano was the site of the Mount Pisgah Volcanic Cinders Mine, a cinder quarry that produced pumice for commercial use, the primary end product being railroad ballast for the Santa Fe Railroad. The mountain is currently owned by Can-Cal Resources Limited, a Canadian company specializing in exploration of precious minerals in California. Mining has had a severe environmental impact; the top of the mountain has been removed and the sides of this histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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 a bowl-shaped crater at the summit. Mechanics of eruption Cinder cones range in size from tens to hundreds of meters tall and often have a bowl-shaped crater at the summit. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggregate (composite)
Aggregate is the component of a composite material that resists compressive stress and provides bulk to the composite material. For efficient filling, aggregate should be much smaller than the finished item, but have a wide variety of sizes. For example, the particles of stone used to make concrete typically include both sand and gravel. Comparison to fiber composites ''Aggregate composites'' tend to be much easier to fabricate, and much more predictable in their finished properties, than '' fiber composites''. Fiber orientation and continuity can have an overwhelming effect, but can be difficult to control and assess. Fabrication aside, aggregate materials themselves also tend to be less expensive; the most common aggregates mentioned above are found in nature and can often be used with only minimal processing. Not all composite materials include aggregate. Aggregate particles tend to have about the same dimensions in every direction (that is, an aspect ratio of about one), so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava
Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or underwater, usually at temperatures from . The volcanic rock resulting from subsequent cooling is also often called ''lava''. A lava flow is an outpouring of lava during an effusive eruption. (An explosive eruption, by contrast, produces a mixture of volcanic ash and other fragments called tephra, not lava flows.) The viscosity of most lava is about that of ketchup, roughly 10,000 to 100,000 times that of water. Even so, lava can flow great distances before cooling causes it to solidify, because lava exposed to air quickly develops a solid crust that insulates the remaining liquid lava, helping to keep it hot and inviscid enough to continue flowing. The word ''lava'' comes from Italian and is probably derived from the Latin word ''labes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amboy Crater
Amboy Crater is a dormant cinder cone volcano that rises above a lava field in the eastern Mojave Desert of southern California, within Mojave Trails National Monument. It is about equidistant from Barstow to the west and Needles to the east, and south of historic U.S. Route 66, near the town of Amboy in San Bernardino County. In 1973, Amboy Crater was designated the Amboy Crater National Natural Landmark. Location The crater's location is southwest of the town of Amboy and the Route 66- National Trails Highway. The Bullion Mountains are to the west, and the Bristol Mountains to the northeast. Description This cinder cone is estimated to be 79,000 years old (+/- 5,000 years)http://alliance.la.asu.edu/rockart/vmltest/PhillipsMojaveTest.pdf . accessed 3/25/2013 and was formed in layers of mostly vesicular pahoehoe during the Pleistocene geological period. The interior has a lava lake. Lava flows as old as Amboy Crater itself blanket the surrounding area. The most rece ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radiocarbon Dating
Radiocarbon dating (also referred to as carbon dating or carbon-14 dating) is a method for determining the age of an object containing organic material by using the properties of radiocarbon, a radioactive isotope of carbon. The method was developed in the late 1940s at the University of Chicago by Willard Libby. It is based on the fact that radiocarbon () is constantly being created in the Earth's atmosphere by the interaction of cosmic rays with atmospheric nitrogen. The resulting combines with atmospheric oxygen to form radioactive carbon dioxide, which is incorporated into plants by photosynthesis; animals then acquire by eating the plants. When the animal or plant dies, it stops exchanging carbon with its environment, and thereafter the amount of it contains begins to decrease as the undergoes radioactive decay. Measuring the amount of in a sample from a dead plant or animal, such as a piece of wood or a fragment of bone, provides information that can be used to calc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mojave National Preserve
Mojave National Preserve is a United States National Preserve located in the Mojave Desert of San Bernardino County, California, USA, between Interstate 15 in California, Interstate 15 and Interstate 40. The preserve was established October 31, 1994, with the passage of the California Desert Protection Act by the US Congress, which also established Joshua Tree National Park and Death Valley National Park as National park, National Parks. Previously, some lands contained within the Preserve were the East Mojave National Scenic Area, under the jurisdiction of the Bureau of Land Management. At , within the contiguous United States it is the third largest unit of the National Park System and the first largest National preserve, National Preserve. The preserve was created within the Pacific West Region of the National Park Service and remains within that jurisdiction today. Natural features include the Kelso Dunes, the Marl Mountains and the Cima Dome & Volcanic Field National Natur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caving
Caving – also known as spelunking in the United States and Canada and potholing in the United Kingdom and Ireland – is the recreational pastime of exploring wild cave systems (as distinguished from show caves). In contrast, speleology is the scientific study of caves and the cave environment.Caving in New Zealand (from Te Ara: The Encyclopedia of New Zealand, Accessed 2012-11.) The challenges involved in caving vary according to the cave being visited; in addition to the total absence of light beyond the entrance, negotiating pitches, squeezes, [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bullion Mountains
The Bullion Mountains are located in the Mojave Desert of California southeast of the city of Barstow. The mountain range stretches for approximately 50 miles in a northwest-southeasterly direction north of Joshua Tree and Twentynine Palms. Since most of the range lies in the Marine Corps Air Ground Combat Center Twentynine Palms The Marine Corps Air Ground Combat Center (MCAGCC), also known as 29 Palms, is the largest United States Marine Corps base. It was a census-designated place (CDP) officially known as Twentynine Palms Base located adjacent to the city of Twentynin ..., where live ammunition practices occur, almost the entire mountain range is off-limits to the public. The highest point of the range in the northwestern region is 4,669 feet (1,423) meters. References *California Road and Recreation Atlas, 2005, pg. 106 Mountain ranges of Southern California Mountain ranges of the Mojave Desert Mountain ranges of San Bernardino County, California {{SanBernardin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lava Bed Mountains
The Lava Bed Mountains are located in the Mojave Desert in southeastern California, United States. The mountains lie in a northwest-southeasterly direction, and are located almost entirely within the Marine Corps Air Ground Combat Center Twentynine Palms, which is a restricted area. The mountains reach a height of above sea level at Argos Mountain, and are found at the northwestern end of the Bullion Mountains. Gays Pass is located at the southern end of the chain, with the Rodman Mountains The Rodman Mountains are located in the Mojave Desert, in San Bernardino County, California, United States. The range is located south of Interstate 40 and Newberry Springs, California, Newberry Springs, and east of the Ord Mountains and northwest ... to the northwest. The Lava Bed Mountains are approximately , and lie in the arid climate zone, characterized by little rainfall. References * Mountain ranges of Southern California Mountain ranges of San Bernardino County, California ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rodman Mountains
The Rodman Mountains are located in the Mojave Desert, in San Bernardino County, California, United States. The range is located south of Interstate 40 and Newberry Springs, and east of the Ord Mountains and northwest of the Bullion Mountains. They are 30 miles southeast of Barstow, California. One of the Cinder cones of the Lavic Lake volcanic field are in the range, with the other three including Pisgah Crater beyond to the east. Wilderness Established in 1994 by the U.S. Congress, the 34,264 acre Rodman Mountains Wilderness is managed by the U.S. Bureau of Land Management as part of the National Wilderness Preservation System. A series of ridges and valleys climbing from 2,000 feet to almost 5,000 feet are the result of faults which cross this wilderness area. A lava flow slices this area in two from northwest to southeast, forming a sloping mesa. Colorful escarpments, calico-colored mountains, maze-like canyons and broad, majestic bajadas come together here. Steep canyons a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
