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39-451: The lake is circular and has a surface area of 19.8 hectares (49 acres). The earlier theories of the crater's origin being a meteorite impact, volcanic cinder, or limestone sinkhole are now discredited. The most likely explanation is that it resulted from the dissolution of underground salt deposits from an anticline , resulting in a kind of sinkhole . There are hot springs nearby in the municipality of Sesquilé , which means "hot water" in

78-598: A doubly plunging anticline , and may be formed from multiple deformations, or superposition of two sets of folds. It may also be related to the geometry of the underlying detachment fault and the varying amount of displacement along the surface of that detachment fault. An anticlinorium is a large anticline in which a series of minor anticlinal folds are superimposed. Examples include the Late Jurassic to Early Cretaceous Purcell Anticlinorium in British Columbia and

117-474: A high rate of compression and seismic activity due to the converging San Andreas Fault. As a result, the Ventura anticline rises at a rate of 5 mm/year with the adjacent Ventura Basin converging at a rate of about 7–10 mm/year. The anticline is composed of a series of sandstone rock beds and an impermeable rock cap under which vast reserves of oil and gas are trapped. Eight different oil bearing zones along

156-460: A non singular point of an algebraic curve is an inflection point if and only if the intersection number of the tangent line and the curve (at the point of tangency) is greater than 2. The main motivation of this different definition, is that otherwise the set of the inflection points of a curve would not be an algebraic set . In fact, the set of the inflection points of a plane algebraic curve are exactly its non-singular points that are zeros of

195-474: A non-stationary point of inflection is the point (0, 0) on the graph of y = x + ax , for any nonzero a . The tangent at the origin is the line y = ax , which cuts the graph at this point. Some functions change concavity without having points of inflection. Instead, they can change concavity around vertical asymptotes or discontinuities. For example, the function x ↦ 1 x {\displaystyle x\mapsto {\frac {1}{x}}}

234-497: A pool at a high mountain peak. Another meaning is "End of the farmfields". Lake Guatavita was reputedly one of the sacred lakes of the Muisca , and a ritual conducted there is widely thought to be the basis for the legend of El Dorado , "the golden one". The legend says the lake is where the Muisca celebrated a ritual in which the zipa (named "El Dorado" by the conquistadors ) was covered in gold dust , and then, venturing out into

273-434: A type of anticlines that have a well-defined, but curved hinge line and are doubly plunging and thus elongate domes . Folds in which the limbs dip toward the hinge and display a more U-like shape are called synclines . They usually flank the sides of anticlines and display opposite characteristics. A syncline's oldest rock strata are in its outer limbs; the rocks become progressively younger toward its hinge. A monocline

312-451: Is a dome . Domes may be created via diapirism from underlying magmatic intrusions or upwardly mobile, mechanically ductile material such as rock salt ( salt dome ) and shale (shale diapir) that cause deformations and uplift in the surface rock. The Richat Structure of the Sahara is considered a dome that has been laid bare by erosion. An anticline which plunges at both ends is termed

351-431: Is a bend in the strata resulting in a local steepening in only one direction of dip. Monoclines have the shape of a carpet draped over a stairstep. An anticline that has been more deeply eroded in the center is called a breached or scalped anticline . Breached anticlines can become incised by stream erosion, forming an anticlinal valley. A structure that plunges in all directions to form a circular or elongate structure

390-424: Is a point on a smooth plane curve at which the curvature changes sign. In particular, in the case of the graph of a function , it is a point where the function changes from being concave (concave downward) to convex (concave upward), or vice versa. For the graph of a function f of differentiability class C (its first derivative f' , and its second derivative f'' , exist and are continuous),

429-427: Is a point on the graph of f at which the tangent crosses the curve. A falling point of inflection is an inflection point where the derivative is negative on both sides of the point; in other words, it is an inflection point near which the function is decreasing. A rising point of inflection is a point where the derivative is positive on both sides of the point; in other words, it is an inflection point near which

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468-462: 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

507-401: Is cylindrical has a well-defined axial surface, whereas non-cylindrical anticlines are too complex to have a single axial plane. An overturned anticline is an asymmetrical anticline with a limb that has been tilted beyond perpendicular , so that the beds in that limb have basically flipped over and may dip in the same direction on both sides of the axial plane. If the angle between the limbs

546-543: Is large (70–120 degrees), then the fold is an "open" fold , but if the angle between the limbs is small (30 degrees or less), then the fold is a "tight" fold . If an anticline plunges (i.e., the anticline crest is inclined to the Earth's surface), it will form V s on a geologic map view that point in the direction of plunge . A plunging anticline has a hinge that is not parallel to the earth's surface. All anticlines and synclines have some degree of plunge. Periclinal folds are

585-521: Is no mechanical contrast between layers in this type of fold. Passive-flow folds are extremely dependent on the rock composition of the stratum and can typically occur in areas with high temperatures. Anticlines, structural domes, fault zones and stratigraphic traps are very favorable locations for oil and natural gas drilling. About 80 percent of the world's petroleum has been found in anticlinal traps. The low density of petroleum causes oil to buoyantly migrate out of its source rock and upward toward

624-442: Is not necessarily the case. If it is the case, the condition that the first nonzero derivative has an odd order implies that the sign of f ' ( x ) is the same on either side of x in a neighborhood of x . If this sign is positive , the point is a rising point of inflection ; if it is negative , the point is a falling point of inflection . Points of inflection can also be categorized according to whether f ' ( x )

663-597: Is the El Dorado anticline in Kansas. The anticline was first tapped into for its petroleum in 1918. Soon after the site became a very prosperous area for entrepreneurs following World War I and the rapid popularization of motor vehicles . By 1995 the El Dorado oil fields had produced 300 million barrels of oil. The central Kansas uplift is an antiform composed of several small anticlines that have collectively produced more than 2.5 million barrels of oil. Another notable anticline

702-535: Is the Tierra Amarilla anticline in San Ysidro, New Mexico. This is a popular hiking and biking site because of the great biodiversity, geologic beauty and paleontological resources. This plunging anticline is made up of Petrified Forest mudstones and sandstone and its caprock is made of Pleistocene and Holocene travertine. The anticline contains springs that deposit carbon dioxide travertine that help to contribute to

741-420: Is the area on the limbs where the curvature changes direction. The axial surface is an imaginary plane connecting the hinge of each layer of rock stratum through the cross section of an anticline. If the axial surface is vertical and the angles on each side of the fold are equivalent, then the anticline is symmetrical. If the axial plane is tilted or offset, then the anticline is asymmetrical. An anticline that

780-443: Is the relative ages of the rock strata that distinguish anticlines from antiforms. The hinge of an anticline refers to the location where the curvature is greatest, also called the crest . The hinge is also the highest point on a stratum along the top of the fold. The culmination also refers to the highest point along any geologic structure. The limbs are the sides of the fold that display less curvature. The inflection point

819-424: Is to bend a deck of cards and to imagine each card as a layer of rock stratum. The amount of slip on each side of the anticline increases from the hinge to the inflection point. Passive-flow folds form when the rock is so soft that it behaves like weak plastic and slowly flows. In this process different parts of the rock body move at different rates causing shear stress to gradually shift from layer to layer. There

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858-412: Is zero or nonzero. A stationary point of inflection is not a local extremum . More generally, in the context of functions of several real variables , a stationary point that is not a local extremum is called a saddle point . An example of a stationary point of inflection is the point (0, 0) on the graph of y = x . The tangent is the x -axis, which cuts the graph at this point. An example of

897-634: The Blue Ridge anticlinorium of northern Virginia and Maryland in the Appalachians, or the Nittany Valley in central Pennsylvania. Anticlines are usually developed above thrust faults, so any small compression and motion within the inner crust can have large effects on the upper rock stratum. Stresses developed during mountain building or during other tectonic processes can similarly warp or bend bedding and foliation (or other planar features). The more

936-514: The Hessian determinant of its projective completion . For a function f , if its second derivative f″ ( x ) exists at x 0 and x 0 is an inflection point for f , then f″ ( x 0 ) = 0 , but this condition is not sufficient for having a point of inflection, even if derivatives of any order exist. In this case, one also needs the lowest-order (above the second) non-zero derivative to be of odd order (third, fifth, etc.). If

975-459: The structural trap for the largest conventional oil field in the world. The Weald–Artois Anticline is a major anticline which outcrops in southeast England and northern France. It was formed from the late Oligocene to middle Miocene , during the Alpine orogeny . Anticlines can have a major effect on the local geomorphology and economy of the regions in which they occur. One example of this

1014-587: The anticline vary greatly from 3,500 to 12,000 feet. The oil and gas formed these pools as they migrated upward during the Pliocene Era and became contained beneath the caprock. This oil field is still active and has a cumulative production of one billion barrels of oil making it one of the most vital historical and economic features of Ventura County. Inflection point In differential calculus and differential geometry , an inflection point , point of inflection , flex , or inflection (rarely inflexion )

1053-429: 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

1092-412: The condition f'' = 0 can also be used to find an inflection point since a point of f'' = 0 must be passed to change f'' from a positive value (concave upward) to a negative value (concave downward) or vice versa as f'' is continuous; an inflection point of the curve is where f'' = 0 and changes its sign at the point (from positive to negative or from negative to positive). A point where

1131-399: The fold causes compression of strata that preferentially erodes to a deeper stratigraphic level relative to the topographically lower flanks. Motion along the fault including both shortening and extension of tectonic plates, usually also deforms strata near the fault. This can result in an asymmetrical or overturned fold. An antiform can be used to describe any fold that is convex up. It

1170-427: The function is increasing. For a smooth curve given by parametric equations , a point is an inflection point if its signed curvature changes from plus to minus or from minus to plus, i.e., changes sign . For a smooth curve which is a graph of a twice differentiable function, an inflection point is a point on the graph at which the second derivative has an isolated zero and changes sign. In algebraic geometry ,

1209-825: The highlands of the Eastern Ranges of the Andes in search of gold. This brought the Spanish into first contact with the Muisca inhabiting the Altiplano Cundiboyacense , including around Lake Guatavita. The lake is a focus of ecotourism, and its association with the legend of El Dorado is also a major attraction. The name of the lake is derived from Chibcha , the language of the Muisca: gwa : mountain or gwata , gwate : high elevation, or gwatibita : high mountain peak; hence,

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1248-444: The lowest-order non-zero derivative is of even order, the point is not a point of inflection, but an undulation point . However, in algebraic geometry, both inflection points and undulation points are usually called inflection points . An example of an undulation point is x = 0 for the function f given by f ( x ) = x . In the preceding assertions, it is assumed that f has some higher-order non-zero derivative at x , which

1287-550: The now-extinct language of Chibcha , once spoken by the local indigenous people, the Muisca . Spanish colonizers and Conquistadors knew about the existence of a sacred lake in the Eastern Ranges of the Andes possibly as early as 1531. The lake was associated with indigenous rituals involving gold. However, the first conquistador to arrive at the actual location was Gonzalo Jiménez de Quesada , possibly in June 1537, while on an expedition to

1326-482: The points of the curve where the curvature changes its sign. For example, the graph of the differentiable function has an inflection point at ( x , f ( x )) if and only if its first derivative f' has an isolated extremum at x . (this is not the same as saying that f has an extremum). That is, in some neighborhood, x is the one and only point at which f' has a (local) minimum or maximum. If all extrema of f' are isolated , then an inflection point

1365-612: The rich diversity of microorganisms. This area also contains remains of fossils and ancient plants from the Jurassic period that are sometimes exposed through geological erosion. The Ventura Anticline is a geologic structure that is part of the Ventura oil fields , the seventh largest oil field in California that was discovered in the 1860s. The anticline runs east to west for 16 miles, dipping steeply 30–60 degrees at both ends. Ventura County has

1404-449: The second derivative vanishes but does not change its sign is sometimes called a point of undulation or undulation point . In algebraic geometry an inflection point is defined slightly more generally, as a regular point where the tangent meets the curve to order at least 3, and an undulation point or hyperflex is defined as a point where the tangent meets the curve to order at least 4. Inflection points in differential geometry are

1443-786: The surface until it is trapped and stored in reservoir rock such as sandstone or porous limestone. The oil becomes trapped along with water and natural gas by a caprock that is made up of impermeable barrier such as an impermeable stratum or fault zone. Examples of low-permeability seals that contain the hydrocarbons, oil and gas, in the ground include shale , limestone , sandstone , and rock salt. The actual type of stratum does not matter as long as it has low permeability. Water, minerals and specific rock strata such as limestone found inside anticlines are also extracted and commercialized. Lastly, ancient fossils are often found in anticlines and are used for paleontological research or harvested into products to be sold. Ghawar Anticline, Saudi Arabia,

1482-435: The underlying fault is tectonically uplifted, the more the strata will be deformed and must adapt to new shapes. The shape formed will also be very dependent on the properties and cohesion of the different types of rock within each layer. During the formation of flexural-slip folds, the different rock layers form parallel-slip folds to accommodate for buckling . A good way to visualize how the multiple layers are manipulated,

1521-459: The water on a ceremonial raft made of rushes, dove into the waters, washing off the gold. Afterward, trinkets, jewelry, and other precious offerings were thrown into the waters by worshipers. A few artifacts of gold and silver found at bottom hold proof to this claim; however, to date, attempts to drain the lake or salvage the gold (see Lake Guatavita gold ) have yielded no more than these. Anticline In structural geology , an anticline

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