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Monocline
A monocline (or, rarely, a monoform) is a step-like fold in rock strata consisting of a zone of steeper dip within an otherwise horizontal or gently-dipping sequence. Formation Monoclines may be formed in several different ways (see diagram) * By differential compaction over an underlying structure, particularly a large fault at the edge of a basin due to the greater compactibility of the basin fill, the amplitude of the fold will die out gradually upwards. * By mild reactivation of an earlier extensional fault during a phase of inversion causing folding in the overlying sequence. * As a form of fault propagation fold during upward propagation of an extensional fault in basement into an overlying cover sequence. * As a form of fault propagation fold during upward propagation of a reverse fault in basement into an overlying cover sequence. Examples * Waterpocket Fold in Capitol Reef National Park, Utah * Comb Ridge in southern Utah * Grandview-Phantom Monocline in Grand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocline01
A monocline (or, rarely, a monoform) is a step-like fold in rock strata consisting of a zone of steeper dip within an otherwise horizontal or gently-dipping sequence. Formation Monoclines may be formed in several different ways (see diagram) * By differential compaction over an underlying structure, particularly a large fault at the edge of a basin due to the greater compactibility of the basin fill, the amplitude of the fold will die out gradually upwards. * By mild reactivation of an earlier extensional fault during a phase of inversion causing folding in the overlying sequence. * As a form of fault propagation fold during upward propagation of an extensional fault in basement into an overlying cover sequence. * As a form of fault propagation fold during upward propagation of a reverse fault in basement into an overlying cover sequence. Examples * Waterpocket Fold in Capitol Reef National Park, Utah *Comb Ridge in southern Utah * Grandview-Phantom Monocline in Grand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monocline
A monocline (or, rarely, a monoform) is a step-like fold in rock strata consisting of a zone of steeper dip within an otherwise horizontal or gently-dipping sequence. Formation Monoclines may be formed in several different ways (see diagram) * By differential compaction over an underlying structure, particularly a large fault at the edge of a basin due to the greater compactibility of the basin fill, the amplitude of the fold will die out gradually upwards. * By mild reactivation of an earlier extensional fault during a phase of inversion causing folding in the overlying sequence. * As a form of fault propagation fold during upward propagation of an extensional fault in basement into an overlying cover sequence. * As a form of fault propagation fold during upward propagation of a reverse fault in basement into an overlying cover sequence. Examples * Waterpocket Fold in Capitol Reef National Park, Utah * Comb Ridge in southern Utah * Grandview-Phantom Monocline in Grand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homocline
In structural geology, a homocline or homoclinal structure (from old el, homo = same, cline = inclination), is a geological structure in which the layers of a sequence of rock strata, either sedimentary or igneous, dip uniformly in a single direction having the same general inclination in terms of direction and angle.Jackson, JA, J Mehl and K Neuendorf (2005) ''Glossary of Geology.'' American Geological Institute, Alexandria, Virginia. 800 pp. Huggett, JR (2011) ''Fundamentals of Geomorphology,'' 3rd ed., Routledge, New York. 516 pp. A homocline can be associated with either one limb of a fold, the edges of a dome, , slice of thrust fault, or a tilted fault block. When the homoclinal strata consists of alternating layers of rock that vary hardness and resistance to erosion, their erosion produces either cuestas, homoclinal ridges, or hogbacks depending on the angle of dip of the strata.Thornbury, W. D., 1954, ''Principles of Geomorphology'' New York ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Purbeck Monocline
The Purbeck Monocline is a geological fold in southern England. The term 'fold' is used in geology when one or more originally flat sedimentary strata surfaces are bent or curved as a result of plastic (i.e. permanent) deformation. A monocline is a step-like fold, in which one limb is roughly horizontal. The Purbeck Monocline was formed during the late Oligocene and early Miocene epochs, about 30 million years ago. It is the northernmost 'ripple' of the Alpine Orogeny. The Purbeck Monocline gives rise to the prominent ridge of steeply dipping Cretaceous chalk which now forms the Purbeck Hills. This chalk band runs from Swyre Head via Flower's Barrow to Old Harry Rocks. From here the fold continues under the sea to The Needles and forms the central spine of the Isle of Wight. Here it is also known as the Purbeck-Isle of Wight Disturbance. The monocline continues under the English Channel as the Wight-Bray Monocline. The Purbeck Hills run east–west through the small broad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fold (geology)
In structural geology, a fold is a stack of originally planar surfaces, such as sedimentary strata, that are bent or curved during permanent deformation. Folds in rocks vary in size from microscopic crinkles to mountain-sized folds. They occur as single isolated folds or in periodic sets (known as ''fold trains''). Synsedimentary folds are those formed during sedimentary deposition. Folds form under varied conditions of stress, pore pressure, and temperature gradient, as evidenced by their presence in soft sediments, the full spectrum of metamorphic rocks, and even as primary flow structures in some igneous rocks. A set of folds distributed on a regional scale constitutes a fold belt, a common feature of orogenic zones. Folds are commonly formed by shortening of existing layers, but may also be formed as a result of displacement on a non-planar fault (''fault bend fold''), at the tip of a propagating fault (''fault propagation fold''), by differential compaction or due to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lebombo Mountains
The Lebombo Mountains, also called Lubombo Mountains ( pt, Montes Libombos), are an , narrow range of mountains in Southern Africa. They stretch from Hluhluwe in KwaZulu-Natal in the south to Punda Maria in the Limpopo Province in South Africa in the north. Parts of the mountain range are also found in Mozambique and Eswatini. Description Geologically, the range is considered a monocline; part of a rifted volcanic margin. The Lebombo monocline was aligned with the Explora Escarpment off-shore Dronning Maud Land, Antarctica, before the break-up of Gondwana. The Lebombo monocline strikes N-S and dips to the east. It is composed of a sequence of Jurassic age volcanic rock, both basaltic lavas and rhyolitic flows and tuffs. The sequence rests on essentially horizontal Karoo Supergroup sedimentary rocks of the Kalahari Craton to the west and is overlain by Cretaceous to recent sediments to the east. The alternating resistant rhyolite and easily eroded basalts produce a series of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Capitol Reef National Park
Capitol Reef National Park is an American national park in south-central Utah. The park is approximately long on its northsouth axis and just wide on average. The park was established in 1971 to preserve of desert landscape and is open all year, with May through September being the highest visitation months. Partially in Wayne County, Utah, the area was originally named "Wayne Wonderland" in the 1920s by local Boosterism, boosters Ephraim P. Pectol and Joseph S. Hickman. Capitol Reef National Park was designated a national monument on August 2, 1937, by President Franklin D. Roosevelt to protect the area's colorful canyons, ridges, buttes, and monoliths; however, it was not until 1950 that the area officially opened to the public. Road access was improved in 1962 with the construction of Utah State Route 24, State Route 24 through the Fremont River (Utah), Fremont River Canyon. The majority of the nearly long up-thrust formation called the Waterpocket Folda rocky Fold (geolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anticline
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grand Hogback
The Grand Hogback is a 70-mile long, curving, spine-like ridge in Western Colorado that extends from near McClure Pass in Pitkin County, Colorado, Pitkin County through Garfield County, Colorado, Garfield County and then to near Meeker, Colorado, Meeker in Rio Blanco County, Colorado, Rio Blanco County. The Hogback (geology), hogback is significant because it marks part of the boundary between the Colorado Plateau to the west and the Southern Rocky Mountains to the east.Colorado Mountain CollegeThe Grand Hogback: Living life on the edge Retrieved: March 27, 2017. The elevation of the ridge ranges from to . The hogback appears as a series of serrated ridges and is easily discernable from Google Maps and other aerial views. It is visible from Interstate 70 in Colorado, Interstate 70. Gaps Rivers have carved out several gaps in the hogback, the most notable being the one the Colorado River has carved out near New Castle, Colorado. Others include Harvey Gap State Park, Harvey Gap a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comb Ridge
Comb Ridge ( nv, ) is a linear north to south-trending monocline nearly 80 miles long in Southeastern Utah and Northeastern Arizona. Its northern end merges with the Abajo Mountains some eleven miles west of Blanding. It extends essentially due south for to the San Juan River. South of the San Juan the ridge turns to the southwest and is more subdued in expression as it extends for an additional to Laguna Creek east of Kayenta, Arizona.''Geosights, Comb Ridge, San Juan County, Utah,'' May 2012, pp. 9–11 USGS 30x60 quadrangle topographic maps: Blanding, Utah-Colorado; Bluff, Utah-Colorado; Rock Point, Arizona-New Mexico; Kayenta, Arizona It was designated a |
Extensional Fault
An extensional fault is a fault caused by stretching of the Earth's crust. Stretching reduces the thickness and horizontally extends portions of the crust and/or lithosphere. In most cases such a fault is also a normal fault, but may create a shallower dip usually associated with a thrust fault. Extensional faults are generally planar. If the stress field is oriented with the maximum stress perpendicular to the Earth's surface, extensional faults will create an initial dip of the associated beds of about 60° from the horizontal. The faults will typically extend down to the base of the seismogenic layer In geophysics and seismology, the seismogenic layer covers the range of depths within the crust or lithosphere in which most earthquakes originate. The thickness is heavily dependent on location. For oceanic crust, the seismogenic layer thicknes .... As crustal stretching continues, the faults will rotate, resulting in steeply-dipping fault blocks between them. See also * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Mountains (Australia)
The Blue Mountains are a mountainous region and a mountain range located in New South Wales, Australia. The region borders on Sydney's metropolitan area, its foothills starting about west of centre of the state capital, close to Penrith on the outskirts of Greater Sydney region. The public's understanding of the extent of the Blue Mountains is varied, as it forms only part of an extensive mountainous area associated with the Great Dividing Range. As defined in 1970, the Blue Mountains region is bounded by the Nepean and Hawkesbury rivers in the east, the Coxs River and Lake Burragorang to the west and south, and the Wolgan and Colo rivers to the north. Geologically, it is situated in the central parts of the Sydney Basin. The ''Blue Mountains Range'' comprises a range of mountains, plateau escarpments extending off the Great Dividing Range about northwest of Wolgan Gap in a generally southeasterly direction for about , terminating at . For about two-thirds of its len ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
