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Marble Mountains (San Bernardino County)
The Marble Mountains are a mountain range in the Eastern Mojave Desert and within Mojave Trails National Monument, in San Bernardino County, California. Geography The Marble Mountains are located just north of Cadiz, California, and are south of Bristol Dry Lake and Amboy, California. The Old Woman Mountains are to the east, and Bullion Mountains to the west. The Sheep Hole Mountains and Twentynine Palms, California are to the southeast. Geology The Marble Mountains contain excellent exposures of Paleozoic sedimentary rocks. The Marble Mountains Fossil Beds are the site of 550 million-year-old fossils of trilobites, which were among the first animals on earth with eyes and skeletons Wilderness Established in 1994 by the U.S. Congress, the Trilobite Wilderness encompasses the Marble Mountain range. The 37,308 acre wilderness area is managed by the Bureau of Land Management The Bureau of Land Management (BLM) is an agency within the United States Department of the Interior ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siskiyou County, California
Siskiyou County (, ) is a county in the northernmost part of the U.S. state of California. As of the 2020 census, the population was 44,076. Its county seat is Yreka and its highest point is Mount Shasta. It falls within the Cascadia bioregion. Siskiyou County is in the Shasta Cascade region along with the Oregon border. Because of its outdoor recreation, Mt. Shasta, McCloud River, and Gold Rush era history, it is an important tourist destination within the state. History Siskiyou County was created on March 22, 1852, from parts of Shasta and Klamath Counties, and named after the Siskiyou mountain range. Parts of the county's territory were given to Modoc County in 1855. The county is the site of the central section of the Siskiyou Trail, which ran between California's Central Valley and the Pacific Northwest. The Siskiyou Trail followed Native American footpaths, and was extended by Hudson's Bay Company trappers in the 1830s. Its length was increased by " Forty-Niners" ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sheep Hole Mountains
The Sheep Hole Mountains are a mountain range in the Mojave Desert, to the north of Joshua Tree National Park, in San Bernardino County, California. The mountains were once Chemehuevi hunting grounds. The mountain range lies between the Bullion Mountains to the west, and the Coxcomb Mountains to the east. The mountains reach an elevation of above sea level just east of Amboy Road, which the range crosses. Sheephole Valley Wilderness Area The Bureau of Land Management designated and manages the Sheephole Valley Wilderness Area which is within the mountain range and Mojave Trails National Monument. The 194,861-acre (approximate) Sheephole Valley Wilderness is a perfect representation of the basin and range topography typical in the Mojave Desert. The area consists of the northwest to southeast trending granitic boulder strewn Sheep Hole and Calumet Mountains, and is adjacent to the northern boundary of Joshua Tree National Park Joshua Tree National Park is an American nat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountain Ranges Of The Mojave Desert
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher than a hill, typically rising at least 300 metres (1,000 feet) above the surrounding land. A few mountains are isolated summits, but most occur in mountain ranges. Mountains are formed through tectonic forces, erosion, or volcanism, which act on time scales of up to tens of millions of years. Once mountain building ceases, mountains are slowly leveled through the action of weathering, through slumping and other forms of mass wasting, as well as through erosion by rivers and glaciers. High elevations on mountains produce colder climates than at sea level at similar latitude. These colder climates strongly affect the ecosystems of mountains: different elevations have different plants and animals. Because of the less hospitable terrain a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bureau Of Land Management
The Bureau of Land Management (BLM) is an agency within the United States Department of the Interior responsible for administering federal lands. Headquartered in Washington DC, and with oversight over , it governs one eighth of the country's landmass. President Harry S. Truman created the BLM in 1946 by combining two existing agencies: the General Land Office and the Grazing Service. The agency manages the federal government's nearly of subsurface mineral estate located beneath federal, state and private lands severed from their surface rights by the Homestead Act of 1862. Most BLM public lands are located in these 12 western states: Alaska, Arizona, California, Colorado, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington and Wyoming. The mission of the BLM is "to sustain the health, diversity, and productivity of the public lands for the use and enjoyment of present and future generations." Originally BLM holdings were described as "land nobody wanted" because home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wilderness Area
Wilderness or wildlands (usually in the plural), are natural environments on Earth that have not been significantly modified by human activity or any nonurbanized land not under extensive agricultural cultivation. The term has traditionally referred to terrestrial environments, though growing attention is being placed on marine wilderness. Recent maps of wilderness suggest it covers roughly one quarter of Earth's terrestrial surface, but is being rapidly degraded by human activity. Even less wilderness remains in the ocean, with only 13.2% free from intense human activity. Some governments establish protection for wilderness areas by law to not only preserve what already exists, but also to promote and advance a natural expression and development. These can be set up in preserves, conservation preserves, national forests, national parks and even in urban areas along rivers, gulches or otherwise undeveloped areas. Often these areas are considered important for the survival of c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite Wilderness Area Sign
Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period () and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 22,000 species having been described. By the time trilobites first appeared in the fossil record, they were already highly diversified and geographically dispersed. Because trilobites had wide diversity and an easily fossilized exoskeleton, they left an extensive fossil record. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trilobite
Trilobites (; meaning "three lobes") are extinct marine arthropods that form the class Trilobita. Trilobites form one of the earliest-known groups of arthropods. The first appearance of trilobites in the fossil record defines the base of the Atdabanian stage of the Early Cambrian period () and they flourished throughout the lower Paleozoic before slipping into a long decline, when, during the Devonian, all trilobite orders except the Proetida died out. The last extant trilobites finally disappeared in the mass extinction at the end of the Permian about 252 million years ago. Trilobites were among the most successful of all early animals, existing in oceans for almost 270 million years, with over 22,000 species having been described. By the time trilobites first appeared in the fossil record, they were already highly diversified and geographically dispersed. Because trilobites had wide diversity and an easily fossilized exoskeleton, they left an extensive fossil record. The stu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedimentary
Sedimentary rocks are types of rock (geology), rock that are formed by the accumulation or deposition of mineral or organic matter, organic particles at Earth#Surface, Earth's surface, followed by cementation (geology), cementation. Sedimentation is the collective name for processes that cause these particles to settle in place. The particles that form a sedimentary rock are called sediment, and may be composed of detritus (geology), geological detritus (minerals) or detritus, biological detritus (organic matter). The geological detritus originated from weathering and erosion of existing rocks, or from the solidification of molten lava blobs erupted by volcanoes. The geological detritus is transported to the place of deposition by water, wind, ice or Mass wasting, mass movement, which are called agents of denudation. Biological detritus was formed by bodies and parts (mainly shells) of dead aquatic organisms, as well as their fecal mass, suspended in water and slowly piling up on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleozoic
The Paleozoic (or Palaeozoic) Era is the earliest of three geologic eras of the Phanerozoic Eon. The name ''Paleozoic'' ( ;) was coined by the British geologist Adam Sedgwick in 1838 by combining the Greek words ''palaiós'' (, "old") and ''zōḗ'' (), "life", meaning "ancient life" ). It is the longest of the Phanerozoic eras, lasting from , and is subdivided into six geologic periods (from oldest to youngest): # Cambrian # Ordovician # Silurian # Devonian # Carboniferous # Permian The Paleozoic comes after the Neoproterozoic Era of the Proterozoic Eon and is followed by the Mesozoic Era. The Paleozoic was a time of dramatic geological, climatic, and evolutionary change. The Cambrian witnessed the most rapid and widespread diversification of life in Earth's history, known as the Cambrian explosion, in which most modern phyla first appeared. Arthropods, molluscs, fish, amphibians, reptiles, and synapsids all evolved during the Paleozoic. Life began in the ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Twentynine Palms, California
Twentynine Palms (also known as 29 Palms) is a city in San Bernardino County, California. Twentynine Palms serves as one of the entry points to Joshua Tree National Park. History Twentynine Palms was named for the palm trees found there in 1852 by Col. Henry Washington while surveying the San Bernardino base line. A post office was established in 1927. A road named Utah Trail honors the late 1800s pioneers on a trail originating in Utah (reportedly Saint George) that went to Twentynine Palms. Nearby is a small Indian reservation belonging to the Twenty-Nine Palms Band of Mission Indians. Joshua Tree National Park, which lies just to the south of Twentynine Palms, was designated a national monument in 1936, and became a national park in 1994. The nearby Marine Corps Air Ground Combat Center Twentynine Palms was founded in 1952. Demographics Its population as of July 1, 2013, was estimated at 25,768. 2010 census At the 2010 census, there were 25,048 people in 8,095 hous ... [...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] |
San Bernardino County, California
San Bernardino County (), officially the County of San Bernardino, is a County (United States), county located in the Southern California, southern portion of the U.S. state of California, and is located within the Inland Empire area. As of the 2020 United States Census, 2020 U.S. Census, the population was 2,181,654, making it the fifth-most populous county in California and the List of the most populous counties in the United States, 14th-most populous in the United States. The county seat is San Bernardino, California, San Bernardino. While included within the Greater Los Angeles area, San Bernardino County is included in the Riverside, California, Riverside–San Bernardino, California, San Bernardino–Ontario, California, Ontario metropolitan statistical area, as well as the Los Angeles–Long Beach, California, Long Beach Greater Los Angeles Area, combined statistical area. With an area of , San Bernardino County is the List of the largest counties in the United States by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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