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62-547: This Park is named after the waterfall that it encompasses, Bridal Veil Falls, which is the 38th highest waterfall in British Columbia . However, it is commonly misstated as the 4th tallest in Canada . The falls drop 122 metres (400 feet) over a wide rock face, creating a "veil-like" effect. Unfortunately, only the bottom 200–250 feet can clearly be viewed from the base due to the viewing-points' location directly at

124-500: 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

186-549: A falls, so almost anything is possible given the right geological and hydrological setting. Waterfalls normally form in a rocky area due to erosion. After a long period of being fully formed, the water falling off the ledge will retreat, causing a horizontal pit parallel to the waterfall wall. Eventually, as the pit grows deeper, the waterfall collapses to be replaced by a steeply sloping stretch of river bed. In addition to gradual processes such as erosion, earth movement caused by earthquakes or landslides or volcanoes can lead to

248-405: A fault as oblique requires both dip and strike components to be measurable and significant. Some oblique faults occur within transtensional and transpressional regimes, and others occur where the direction of extension or shortening changes during the deformation but the earlier formed faults remain active. The hade angle is defined as the complement of the dip angle; it is the angle between

310-582: A fault hosting valuable porphyry copper deposits is northern Chile's Domeyko Fault with deposits at Chuquicamata , Collahuasi , El Abra , El Salvador , La Escondida and Potrerillos . Further south in Chile Los Bronces and El Teniente porphyry copper deposit lie each at the intersection of two fault systems. Faults may not always act as conduits to surface. It has been proposed that deep-seated "misoriented" faults may instead be zones where magmas forming porphyry copper stagnate achieving

372-489: A fault plane, where it becomes locked, are called asperities . Stress builds up when a fault is locked, and when it reaches a level that exceeds the strength threshold, the fault ruptures and the accumulated strain energy is released in part as seismic waves , forming an earthquake . Strain occurs accumulatively or instantaneously, depending on the liquid state of the rock; the ductile lower crust and mantle accumulate deformation gradually via shearing , whereas

434-408: A fault's age by studying soil features seen in shallow excavations and geomorphology seen in aerial photographs. Subsurface clues include shears and their relationships to carbonate nodules , eroded clay, and iron oxide mineralization, in the case of older soil, and lack of such signs in the case of younger soil. Radiocarbon dating of organic material buried next to or over a fault shear

496-427: A hanging wall or foot wall where a thrust fault formed along a relatively weak bedding plane is known as a flat and a section where the thrust fault cut upward through the stratigraphic sequence is known as a ramp . Typically, thrust faults move within formations by forming flats and climbing up sections with ramps. This results in the hanging wall flat (or a portion thereof) lying atop the foot wall ramp as shown in

558-484: A major fault. Synthetic faults dip in the same direction as the major fault while the antithetic faults dip in the opposite direction. These faults may be accompanied by rollover anticlines (e.g. the Niger Delta Structural Style). All faults have a measurable thickness, made up of deformed rock characteristic of the level in the crust where the faulting happened, of the rock types affected by

620-400: A manner that creates multiple listric faults. The fault panes of listric faults can further flatten and evolve into a horizontal or near-horizontal plane, where slip progresses horizontally along a decollement . Extensional decollements can grow to great dimensions and form detachment faults , which are low-angle normal faults with regional tectonic significance. Due to the curvature of

682-421: A non-vertical fault are known as the hanging wall and footwall . The hanging wall occurs above the fault plane and the footwall occurs below it. This terminology comes from mining: when working a tabular ore body, the miner stood with the footwall under his feet and with the hanging wall above him. These terms are important for distinguishing different dip-slip fault types: reverse faults and normal faults. In

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744-465: A pioneering work on waterfalls. In 1942 Oscar von Engeln wrote of the lack of research on waterfalls: Waterfall sites more than any other geomorphic feature attract and hold the interest of the general public. Because they have such a popular approval waterfalls are not given serious attention by some students of systematic geomorphology. This attitude is not to be commended. Waterfalls are significant items for geomorphic investigation. As late as 1985

806-464: A reverse fault, the hanging wall displaces upward, while in a normal fault the hanging wall displaces downward. Distinguishing between these two fault types is important for determining the stress regime of the fault movement. Faults are mainly classified in terms of the angle that the fault plane makes with the Earth's surface, known as the dip , and the direction of slip along the fault plane. Based on

868-795: A role in many cultures, as religious sites and subjects of art and music. Many artists have painted waterfalls and they are referenced in many songs, such as those of the Kaluli people in Papua New Guinea . Michael Harner titled his study of the Jivaroan peoples of Ecuador The Jivaro: People of the Sacred Waterfalls. Artists such as those of the Hudson River School and J. M. W. Turner and John Sell Cotman painted particularly notable pictures of waterfalls in

930-603: A scholar felt that "waterfalls remain a very much neglected aspect of river studies". Studies of waterfalls increased dramatically in the second half of the 20th century. Numerous waterfall guidebooks exist, and the World Waterfall Database is a website cataloging thousands of waterfalls. Many explorers have visited waterfalls. European explorers recorded waterfalls they came across. In 1493, Christopher Columbus noted Carbet Falls in Guadeloupe , which

992-506: A stream or river flowing into a glacier continues to flow into a valley after the glacier has receded or melted. The large waterfalls in Yosemite Valley are examples of this phenomenon, which is referred to as a hanging valley . Another reason hanging valleys may form is where two rivers join and one is flowing faster than the other. When warm and cold water meets by a gorge in the ocean, large underwater waterfalls can form as

1054-461: A top layer of resistant bedrock before falling onto softer rock, which erodes faster, leading to an increasingly high fall. Waterfalls have been studied for their impact on species living in and around them. Humans have had a distinct relationship with waterfalls since prehistory, travelling to see them, exploring and naming them. They can present formidable barriers to navigation along rivers. Waterfalls are religious sites in many cultures. Since

1116-408: A wall of ice that is often unstable. Consequently, the base of the falls becomes an extremely hazardous area, leading to the closure of the park during the winter season. While the falls are frozen solid, they become a sought-after destination for ice climb . However, climbers recognize the difficulty of climbing in these conditions and the infrequency of stable climbing conditions. Bridal Veil Falls

1178-422: Is a horst . A sequence of grabens and horsts on the surface of the Earth produces a characteristic basin and range topography . Normal faults can evolve into listric faults, with their plane dip being steeper near the surface, then shallower with increased depth, with the fault plane curving into the Earth. They can also form where the hanging wall is absent (such as on a cliff), where the footwall may slump in

1240-410: Is a stub . You can help Misplaced Pages by expanding it . Waterfall A waterfall is any point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf . Waterfalls can be formed in several ways, but the most common method of formation is that a river courses over

1302-408: Is a type of stream pool formed at the bottom of a waterfall. A waterfall may also be referred to as a "foss" or "force". Waterfalls are commonly formed in the upper course of a river where lakes flow into valleys in steep mountains. A river sometimes flows over a large step in the rocks that may have been formed by a fault line . Waterfalls can occur along the edge of a glacial trough , where

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1364-423: Is a zone of folding close to a fault that likely arises from frictional resistance to movement on the fault. The direction and magnitude of heave and throw can be measured only by finding common intersection points on either side of the fault (called a piercing point ). In practice, it is usually only possible to find the slip direction of faults, and an approximation of the heave and throw vector. The two sides of

1426-824: Is also no agreement how to measure the height of a waterfall, or even what constitutes one. Angel Falls in Venezuela is the tallest waterfall in the world , the Khone Phapheng Falls in Laos are the widest, and the Inga Falls on the Congo River are the biggest by flow rate , while the Dry Falls in Washington are the largest confirmed waterfalls ever. The highest known subterranean waterfall

1488-544: Is defined by the direction of movement of the ground as would be seen by an observer on the opposite side of the fault. A special class of strike-slip fault is the transform fault when it forms a plate boundary. This class is related to an offset in a spreading center , such as a mid-ocean ridge , or, less common, within continental lithosphere , such as the Dead Sea Transform in the Middle East or

1550-466: Is fractured or otherwise more erodible. Hydraulic jets and hydraulic jumps at the toe of a falls can generate large forces to erode the bed, especially when forces are amplified by water-borne sediment. Horseshoe-shaped falls focus the erosion to a central point, also enhancing riverbed change below a waterfall. A process known as "potholing" involves local erosion of a potentially deep hole in bedrock due to turbulent whirlpools spinning stones around on

1612-588: Is in Vrtoglavica Cave in Slovenia . The Denmark Strait cataract is an undersea overflow which could be considered a "waterfall" under a very broad usage of that term; if so included, it is the largest known waterfall. Artificial waterfalls are water features or fountains that imitate a natural waterfall. The Cascata delle Marmore is the tallest artificially built waterfall at 541 feet (165 m). Fault (geology) In geology ,

1674-543: Is often critical in distinguishing active from inactive faults. From such relationships, paleoseismologists can estimate the sizes of past earthquakes over the past several hundred years, and develop rough projections of future fault activity. Many ore deposits lie on or are associated with faults. This is because the fractured rock associated with fault zones allow for magma ascent or the circulation of mineral-bearing fluids. Intersections of near-vertical faults are often locations of significant ore deposits. An example of

1736-492: Is particularly clear in the case of detachment faults and major thrust faults . The main types of fault rock include: In geotechnical engineering , a fault often forms a discontinuity that may have a large influence on the mechanical behavior (strength, deformation, etc.) of soil and rock masses in, for example, tunnel , foundation , or slope construction. The level of a fault's activity can be critical for (1) locating buildings, tanks, and pipelines and (2) assessing

1798-425: 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,

1860-804: Is undoubtedly presented by the continent of Africa, the 'darkness' of which is almost entirely due to this cause." Waterfalls are often visited by people simply to see them. Hudson theorizes that they make good tourism sites because they are generally considered beautiful and are relatively uncommon. Activities at waterfalls can include bathing, swimming, photography, rafting , canyoning , abseiling , rock climbing , and ice climbing . Waterfalls can also be sites for generating hydroelectric power and can hold good fishing opportunities. Wealthy people were known to visit areas with features such as waterfalls at least as early as in Ancient Rome and China . However, many waterfalls were essentially inaccessible due to

1922-762: The Alpine Fault in New Zealand. Transform faults are also referred to as "conservative" plate boundaries since the lithosphere is neither created nor destroyed. Dip-slip faults can be either normal (" extensional ") or reverse . The terminology of "normal" and "reverse" comes from coal mining in England, where normal faults are the most common. With the passage of time, a regional reversal between tensional and compressional stresses (or vice-versa) might occur, and faults may be reactivated with their relative block movement inverted in opposite directions to

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1984-477: The Gocta Cataracts were first announced to the world in 2006. Waterfalls can pose major barriers to travel. Canals are sometimes built as a method to go around them, other times things must be physically carried around or a railway built . In 1885, the geographer George Chisholm wrote that, "The most signal example of the effect of waterfalls and rapids in retarding the development of civilisation

2046-541: The black swift and white-throated dipper . These species preferentially nest in the space behind the falling water, which is thought to be a strategy to avoid predation. Some waterfalls are also distinct in that they do not flow continuously. Ephemeral waterfalls only flow after a rain or a significant snowmelt. Waterfalls can also be found underground and in oceans. The geographer Andrew Goudie wrote in 2020 that waterfalls have received "surprisingly limited research." Alexander von Humboldt wrote about them in

2108-657: The seismic shaking and tsunami hazard to infrastructure and people in the vicinity. In California, for example, new building construction has been prohibited directly on or near faults that have moved within the Holocene Epoch (the last 11,700 years) of the Earth's geological history. Also, faults that have shown movement during the Holocene plus Pleistocene Epochs (the last 2.6 million years) may receive consideration, especially for critical structures such as power plants, dams, hospitals, and schools. Geologists assess

2170-400: The 1820s. There is no name for the specific field of researching waterfalls, and in the published literature been described as "scattered", though it is popular to describe studying waterfalls as "waterfallology". An early paper written on waterfalls was published in 1884 by William Morris Davis , a geologist known as the "father of American geography". In the 1930s Edward Rashleigh published

2232-444: The 18th century, they have received increased attention as tourist destinations, sources of hydropower , and—particularly since the mid-20th century—as subjects of research. A waterfall is generally defined as a point in a river where water flows over a steep drop that is close to or directly vertical. In 2000 Mabin specified that "The horizontal distance between the positions of the lip and plunge pool should be no more than c 25% of

2294-703: The 19th century. One of the versions of the Shinto purification ceremony of misogi involves standing underneath a waterfall in ritual clothing. In Japan the Nachi Falls are a site of pilgrimage, as are falls near Tirupati , India, and the Saut-d'Eau , Haiti. The Otavalos use Piguchi waterfall as part of the Churru ritual which serves as a coming of age ceremony. Many waterfalls in Africa were places of worship for

2356-426: The base of the waterfall by abrasion , creating a deep plunge pool in the gorge downstream. Streams can become wider and shallower just above waterfalls due to flowing over the rock shelf, and there is usually a deep area just below the waterfall because of the kinetic energy of the water hitting the bottom. However, a study of waterfalls systematics reported that waterfalls can be wider or narrower above or below

2418-492: The base. It is located at the south end of the land set aside as provincial Park. Their source is Mount Archibald , and they flow into Bridal Creek, which then travels to Cheam Lake Wetlands Regional Park and finally to the Fraser River . During drier summer months, the volume of the water decreases significantly, reducing the visual impact of the waterfall. Bridal Veil Falls tend to freeze during cold winters, creating

2480-441: The bed, drilling it out. Sand and stones carried by the watercourse therefore increase erosion capacity. This causes the waterfall to carve deeper into the bed and to recede upstream. Often over time, the waterfall will recede back to form a canyon or gorge downstream as it recedes upstream, and it will carve deeper into the ridge above it. The rate of retreat for a waterfall can be as high as one-and-a-half metres per year. Often,

2542-403: The brittle upper crust reacts by fracture – instantaneous stress release – resulting in motion along the fault. A fault in ductile rocks can also release instantaneously when the strain rate is too great. Slip is defined as the relative movement of geological features present on either side of a fault plane. A fault's sense of slip is defined as the relative motion of the rock on each side of

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2604-401: The cold water rushes to the bottom. The caprock model of waterfall formation states that the river courses over resistant bedrock , erosion happens slowly and is dominated by impacts of water-borne sediment on the rock, while downstream the erosion occurs more rapidly. As the watercourse increases its velocity at the edge of the waterfall, it may pluck material from the riverbed, if the bed

2666-436: The direction of slip, faults can be categorized as: In a strike-slip fault (also known as a wrench fault , tear fault or transcurrent fault ), the fault surface (plane) is usually near vertical, and the footwall moves laterally either left or right with very little vertical motion. Strike-slip faults with left-lateral motion are also known as sinistral faults and those with right-lateral motion as dextral faults. Each

2728-678: The environment of the waterfall itself. A 2012 study of the Agbokim Waterfalls , has suggested that they hold biodiversity to a much higher extent than previously thought. Waterfalls also affect terrestrial species. They create a small microclimate in their immediate vicinity characterized by cooler temperatures and higher humidity than the surrounding region, which may support diverse communities of mosses and liverworts . Species of these plants may have disjunct populations at waterfall zones far from their core range. Waterfalls provide nesting cover for several species of bird, such as

2790-456: The fault and of the presence and nature of any mineralising fluids . Fault rocks are classified by their textures and the implied mechanism of deformation. A fault that passes through different levels of the lithosphere will have many different types of fault rock developed along its surface. Continued dip-slip displacement tends to juxtapose fault rocks characteristic of different crustal levels, with varying degrees of overprinting. This effect

2852-402: The fault concerning the other side. In measuring the horizontal or vertical separation, the throw of the fault is the vertical component of the separation and the heave of the fault is the horizontal component, as in "Throw up and heave out". The vector of slip can be qualitatively assessed by studying any drag folding of strata, which may be visible on either side of the fault. Drag folding

2914-576: The fault plane and a vertical plane that strikes parallel to the fault. Ring faults , also known as caldera faults , are faults that occur within collapsed volcanic calderas and the sites of bolide strikes, such as the Chesapeake Bay impact crater . Ring faults are the result of a series of overlapping normal faults, forming a circular outline. Fractures created by ring faults may be filled by ring dikes . Synthetic and antithetic are terms used to describe minor faults associated with

2976-401: The fault plane, the horizontal extensional displacement on a listric fault implies a geometric "gap" between the hanging and footwalls of the fault forms when the slip motion occurs. To accommodate into the geometric gap, and depending on its rheology , the hanging wall might fold and slide downwards into the gap and produce rollover folding , or break into further faults and blocks which fil in

3038-427: The fault-bend fold diagram. Thrust faults form nappes and klippen in the large thrust belts. Subduction zones are a special class of thrusts that form the largest faults on Earth and give rise to the largest earthquakes. A fault which has a component of dip-slip and a component of strike-slip is termed an oblique-slip fault . Nearly all faults have some component of both dip-slip and strike-slip; hence, defining

3100-415: The formation of waterfalls. Waterfalls are an important factor in determining the distribution of lotic organisms such as fish and aquatic invertebrates, as they may restrict dispersal along streams. The presence or absence of certain species can have cascading ecological effects, and thus cause differences in trophic regimes above and below waterfalls. Certain aquatic plants and insects also specialize in

3162-475: The gap. If faults form, imbrication fans or domino faulting may form. A reverse fault is the opposite of a normal fault—the hanging wall moves up relative to the footwall. Reverse faults indicate compressive shortening of the crust. A thrust fault has the same sense of motion as a reverse fault, but with the dip of the fault plane at less than 45°. Thrust faults typically form ramps, flats and fault-bend (hanging wall and footwall) folds. A section of

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3224-661: The native peoples and got their names from gods in the local religion. "In Chinese tradition, the waterfall represents" the season of autumn , yin , and the Chinese dragon 's power over water that comes from the former two. There are thousands of waterfalls in the world, though no exact number has been calculated. The World Waterfall Database lists 7,827 as of 2013, but this is likely incomplete; as noted by Hudson, over 90% of their listings are in North America. Many guidebooks to local waterfalls have been published. There

3286-500: The original movement (fault inversion). In such a way, a normal fault may therefore become a reverse fault and vice versa. In a normal fault, the hanging wall moves downward, relative to the footwall. The dip of most normal faults is at least 60 degrees but some normal faults dip at less than 45 degrees. A downthrown block between two normal faults dipping towards each other is a graben . A block stranded between two grabens, and therefore two normal faults dipping away from each other,

3348-412: The right time for—and type of— igneous differentiation . At a given time differentiated magmas would burst violently out of the fault-traps and head to shallower places in the crust where porphyry copper deposits would be formed. As faults are zones of weakness, they facilitate the interaction of water with the surrounding rock and enhance chemical weathering . The enhanced chemical weathering increases

3410-728: The rise of Romanticism , and increased importance of hydropower with the Industrial Revolution . European explorers often preferred to give waterfalls names in their own language; for instance, David Livingstone named Victoria Falls after Queen Victoria , though it was known by local peoples as Mosi-oa-Tunya. Many waterfalls have descriptive names which can come from the river they are on, places they are near, their features, or events that happened near them. Some countries that were colonized by European nations have taken steps to return names to waterfalls previously renamed by European explorers. Exploration of waterfalls continues;

3472-504: The rock stratum just below the more resistant shelf will be of a softer type, meaning that undercutting due to splashback will occur here to form a shallow cave-like formation known as a rock shelter under and behind the waterfall. Eventually, the outcropping , more resistant cap rock will collapse under pressure to add blocks of rock to the base of the waterfall. These blocks of rock are then broken down into smaller boulders by attrition as they collide with each other, and they also erode

3534-468: The term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the distinction, as the rock between the faults is converted to fault-bound lenses of rock and then progressively crushed. Due to friction and the rigidity of the constituent rocks, the two sides of a fault cannot always glide or flow past each other easily, and so occasionally all movement stops. The regions of higher friction along

3596-546: The treacherous terrain surrounding them until improvements began to be made such as paths to the falls, becoming common across the United Kingdom and America in the 1800s and continuing through the 1900s and into the 21st century. Remote waterfalls are now often visited by air travel. Human development has also threatened many waterfalls. For instance, the Guaíra Falls , once one of the most powerful waterfalls in

3658-423: The waterfall height." There are various types and methods to classify waterfalls. Some scholars have included rapids as a subsection. What actually constitutes a waterfall continues to be debated. Waterfalls are sometimes interchangeably referred to as "cascades" and "cataracts", though some sources specify a cataract as being a larger and more powerful waterfall and a cascade as being smaller. A plunge pool

3720-677: The world, were submerged in 1982 by a human-made dam, as were the Ripon Falls in 1952. Conversely, other waterfalls have seen significantly lower water levels as a result of diversion for hydroelectricity , such as the Tyssestrengene in Norway. Development of the areas around falls as tourist attractions has also destroyed the natural scene around many of them. Waterfalls are included on thirty-eight World Heritage Sites and many others are protected by governments. Waterfalls play

3782-551: Was likely the first waterfall Europeans recorded seeing in the Americas. In the late 1600s, Louis Hennepin visited North America, providing early descriptions of Niagara Falls and the Saint Anthony Falls . The geographer Brian J. Hudson argues that it was uncommon to specifically name waterfalls until the 1700s. The trend of Europeans specifically naming falls was in tandem with increased scientific focus on nature,

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3844-497: Was named in the 19th century by the village of Popkum . In the early 20th century, the village used the waterfall with a hydro-electric generator to power the chalet and heated swimming pool in the village. Only the concrete foundation of the generator can be found today. 49°11′N 121°44′W  /  49.183°N 121.733°W  / 49.183; -121.733  ( Bridal Veil Falls Provincial Park ) This British Columbia protected areas related article

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