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Whipple Mountains
The Whipple Mountains ( Mojave: Avii Kur'utat; Chemehuevi: Wiyaatuʷa̱) are located in eastern San Bernardino County, California. They are directly west of the Colorado River, Parker Dam, and Lake Havasu; south of Needles, California; north of Parker, Arizona and Vidal, California; and northeast of Vidal Junction, California. The mountain forms a major direction change of the north-south Colorado River as it changes directions to southeast, then southwest around the eastern perimeter of the Whipple Mountains. The highest point of the mountains, and the Whipple Mountains Wilderness is Whipple Mountain at . The western portion of the mountain range has pale green formations, differing from the eastern, steeply carved and striking brick-red volcanics. Landforms are diverse and range from valley floors and washes to steep-walled canyons, domed peaks, natural bridges, and eroded spires.U.S. Bureau of Land Management websit''Whipple Mountains Wilderness'' Retrieved 2011-01-27 Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado Desert
California's Colorado Desert is a part of the larger Sonoran Desert. It encompasses approximately , including the heavily irrigated Coachella and Imperial valleys. It is home to many unique flora and fauna. Geography and geology The Colorado Desert is a subdivision of the larger Sonoran Desert encompassing approximately . The desert encompasses Imperial County and includes parts of San Diego County, Riverside County, and a small part of San Bernardino County, California, United States. Most of the Colorado Desert lies at a relatively low elevation, below , with the lowest point of the desert floor at below sea level, at the Salton Sea. Although the highest peaks of the Peninsular Ranges reach elevations of nearly , most of the region's mountains do not exceed . In this region, the geology is dominated by the transition of the tectonic plate boundary from rift to fault. The southernmost strands of the San Andreas Fault connect to the northernmost extensions of the East Pacif ... [...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] |
Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start of the Cenozoic Era, and extended to the beginning of the Quaternary glaciation at the end of the Pliocene Epoch. The time span covered by the Tertiary has no exact equivalent in the current geologic time system, but it is essentially the merged Paleogene and Neogene periods, which are informally called the Early Tertiary and the Late Tertiary, respectively. The Tertiary established the Antarctic as an icy island continent. Historical use of the term The term Tertiary was first used by Giovanni Arduino during the mid-18th century. He classified geologic time into primitive (or primary), secondary, and tertiary periods based on observations of geology in Northern Italy. Later a fourth period, the Quaternary, was applied. In the early d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mylonite
Mylonite is a fine-grained, compact metamorphic rock produced by dynamic recrystallization of the constituent minerals resulting in a reduction of the grain size of the rock. Mylonites can have many different mineralogical compositions; it is a classification based on the textural appearance of the rock. Formation Mylonites are ductilely deformed rocks formed by the accumulation of large shear strain, in ductile fault zones. There are many different views on the formation of mylonites, but it is generally agreed that crystal-plastic deformation must have occurred, and that fracturing and cataclastic flow are secondary processes in the formation of mylonites. Mechanical abrasion of grains by milling does not occur, although this was originally thought to be the process that formed mylonites, which were named from the Greek μύλος ''mylos'', meaning mill. Mylonites form at depths of no less than 4 km. There are many different mechanisms that accommodate crystal-plastic def ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antiform
In structural geology, an anticline is a type of fold that is an arch-like shape and has its oldest beds at its core, whereas a syncline is the inverse of an anticline. A typical anticline is convex up in which the hinge or crest is the location where the curvature is greatest, and the limbs are the sides of the fold that dip away from the hinge. Anticlines can be recognized and differentiated from antiforms by a sequence of rock layers that become progressively older toward the center of the fold. Therefore, if age relationships between various rock strata are unknown, the term antiform should be used. The progressing age of the rock strata towards the core and uplifted center, are the trademark indications for evidence of anticlines on a geologic map. These formations occur because anticlinal ridges typically develop above thrust faults during crustal deformations. The uplifted core of the fold causes compression of strata that preferentially erodes to a deeper strati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Core Complex
Metamorphic core complexes are exposures of deep crust exhumed in association with largely amagmatic extension. They form, and are exhumed, through relatively fast transport of middle and lower continental crust to the Earth's surface. During this process, high-grade metamorphic rocks (eclogite-, granulite- to amphibolite- facies) are exposed below low-angle detachment faults (and mylonitic shear zones) that show ductile deformation on the lower side (footwall) with amphibolite- to greenschist-facies syndeformational metamorphism, and ductile-brittle to brittle deformation on the upper-side (hanging-wall) with tilted geometries. Descriptions * stated that they: are characterized by a generally heterogeneous, older metamorphic-plutonic basement terrane overprinted by low-dipping lineated and foliated mylonitic and gneissic fabrics. An unmetamorphosed cover terrane is typically attenuated and sliced by numerous subhorizontal younger-on-older faults. Between the basem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Detachment Fault
A detachment fault is a gently dipping normal fault associated with large-scale extensional tectonics. Detachment faults often have very large displacements (tens of km) and juxtapose unmetamorphosed hanging walls against medium to high-grade metamorphic footwalls that are called metamorphic core complexes. They are thought to have formed as either initially low-angle structures or by the rotation of initially high-angle normal faults modified also by the isostatic effects of tectonic denudation. They may also be called denudation faults. Examples of detachment faulting include: *The Snake Range detachment system of the Basin and Range Province of western North America which was active during the Miocene *The Nordfjord-Sogn detachment of western Norway active during the Devonian Period *The Whipple detachment in southeastern California Detachment faults have been found on the sea floor close to divergent plate boundaries characterised by a limited supply of upwelling magma, su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hanging Wall
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arroyo (creek)
An arroyo (; from Spanish arroyo , "brook"), also called a wash, is a dry stream, creek, stream bed or gulch that temporarily or seasonally fills and flows after sufficient rain. Flash floods are common in arroyos following thunderstorms. ''Wadi'' (Arabic) is used in North Africa and Western Asia for similar landforms. The desert dry wash biome is restricted to the arroyos of the southwestern United States. Arroyos provide a water source to desert animals. Types and processes Arroyos can be natural fluvial landforms or constructed flood control channels. The term usually applies to a Grade (slope), sloped or mountainous terrain in xeric and desert climates. In addition: in many rural communities arroyos are also the principal transportation routes; and in many urban communities arroyos are also parks and recreational locations, often with linear multi-use bicycle, pedestrian, and equestrian trails. Flash flooding can cause the deep arroyos or deposition of sediment on flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whipple Wash WikiMediaCommons
Whipple may refer to: People *Whipple (surname) (including a list of people with the surname) *Whip Jones (1909–2001), American ski industry pioneer, founder, developer and original operator of the Aspen Highlands ski area in Aspen, Colorado * Whipple Van Buren Phillips (1833–1904), American businessman, grandfather of H. P. Lovecraft, whom he raised Fictional characters *Mr. Whipple, in American television ads for Charmin toilet paper * Whipple Jones (''The Bold and the Beautiful''), in the American soap opera ''The Bold and the Beautiful'' Places in the United States *Whipple, Ohio, an unincorporated community *Whipple, West Virginia, an unincorporated community * Whipple Lakes, Crow Wing County, Minnesota * Whipple Lake, Clearwater County, Minnesota *Whipple Mountains, a mountain range in southeastern California * Whipple Run, a stream in Ohio In the military *, three U.S. Navy ships named after Abraham Whipple *Fort Whipple, Arizona, a fort established in 1863 in Arizona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemehuevi Mountains
The Chemehuevi Mountains are found at the southeast border of San Bernardino County in southeastern California adjacent the Colorado River. Located south of Needles, California and northwest of the Whipple Mountains, the mountains lie in a north–south direction in general, and are approximately in length. Geography The mountains are located between U.S. Route 95 and the Topock Gorge of the River, just south of Interstate 40. Whale Mountain, at , is found at the northern end of the range about five miles east of Lobecks Pass. The Chemehuevi range reaches at its highpoint, Chemehuevi Peak, located at the range's extreme southwest, bordering Chemehuevi Valley and Wash, where the valley turns due-east to meet the Colorado River. Chemehuevi Mountains Wilderness The Chemehuevi Mountains Wilderness Area encompasses the rugged, granitic Chemehuevi Mountains. The mountain range is horseshoe-shaped, with the open end facing eastward toward the Colorado River. Contained within the ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mopah Range
The Mopah Range is a desert mountain range, in the Lower Colorado River Valley region, in southeastern San Bernardino County, California. Geography The Mopah Range are located directly adjacent to and linked with the larger Turtle Mountains Range. They are in the northern Colorado Desert region of the Sonoran Desert, and the southern reach of Mojave Desert. The Colorado River and Whipple Mountains are to the east, and the Iron Mountains to the west. Vidal Junction, California is to the southeast, and the Colorado River Aqueduct passes to the south. Turtle Mountains Wilderness Area The Mopah Range is part of the Turtle Mountains Wilderness Area. The Mopahs include broad bajadas to highly eroded volcanic peaks, spires, and cliffs. The Mopah Range contains the two signature Mopah Peaks, which are rhyodactic or volcanic plugs. The northernmost peak is a landmark known as Mexican Hat. The area has numerous springs and seeps. The Mopahs are considered part of the greater Lower Col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
