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93-586: Poldark Mine is a tourist attraction near the town of Helston in Cornwall , England, UK. It lies within the Wendron Mining District of the Cornwall and West Devon Mining Landscape World Heritage Site . Its features include underground guided tours through ancient tin mine workings; a museum of industrial heritage, mining equipment and Cornish social history; and a scheduled ancient monument and riverside gardens. It opened in 1972 as Wendron Forge and

186-461: A blowing house . The mine workings discovered in the 1970s were attributed by A. K. Hamilton Jenkin to an old tin mine known as Wheal Roots, which had probably been worked between about 1720 and 1780. By 1856 it had become part of the Wendron Consols mine and is shown on the surface plan of that mine as 'old men's workings' meaning that it was at that date considered a very old mine. The mine

279-429: A glacial armor . Ice can not only erode mountains but also protect them from erosion. Depending on glacier regime, even steep alpine lands can be preserved through time with the help of ice. Scientists have proved this theory by sampling eight summits of northwestern Svalbard using Be10 and Al26, showing that northwestern Svalbard transformed from a glacier-erosion state under relatively mild glacial maxima temperature, to

372-502: A 30-inch beam engine was acquired from the now abandoned village of Greensplat where it had been pumping 500 gallons of slurry a minute from a depth of 240 feet at a china clay pit near St Austell . The engine was the last to work in commercial service in Cornwall when it was stopped in 1959. The engine dates from 1850 when it was built for the Bunny tin mine. It took eight months in 1972 for

465-426: A considerable depth. A gully is distinguished from a rill based on a critical cross-sectional area of at least one square foot, i.e. the size of a channel that can no longer be erased via normal tillage operations. Extreme gully erosion can progress to formation of badlands . These form under conditions of high relief on easily eroded bedrock in climates favorable to erosion. Conditions or disturbances that limit

558-408: A fall in sea level, can produce a distinctive landform called a raised beach . Chemical erosion is the loss of matter in a landscape in the form of solutes . Chemical erosion is usually calculated from the solutes found in streams. Anders Rapp pioneered the study of chemical erosion in his work about Kärkevagge published in 1960. Formation of sinkholes and other features of karst topography

651-409: A few millimetres, or for thousands of kilometres. Agents of erosion include rainfall ; bedrock wear in rivers ; coastal erosion by the sea and waves ; glacial plucking , abrasion , and scour; areal flooding; wind abrasion; groundwater processes; and mass movement processes in steep landscapes like landslides and debris flows . The rates at which such processes act control how fast

744-479: A glacier-armor state occupied by cold-based, protective ice during much colder glacial maxima temperatures as the Quaternary ice age progressed. These processes, combined with erosion and transport by the water network beneath the glacier, leave behind glacial landforms such as moraines , drumlins , ground moraine (till), glaciokarst , kames, kame deltas, moulins, and glacial erratics in their wake, typically at

837-464: A homogeneous bedrock erosion pattern, curved channel cross-section beneath the ice is created. Though the glacier continues to incise vertically, the shape of the channel beneath the ice eventually remain constant, reaching a U-shaped parabolic steady-state shape as we now see in glaciated valleys . Scientists also provide a numerical estimate of the time required for the ultimate formation of a steady-shaped U-shaped valley —approximately 100,000 years. In

930-423: A large river can remove enough sediments to produce a river anticline , as isostatic rebound raises rock beds unburdened by erosion of overlying beds. Shoreline erosion, which occurs on both exposed and sheltered coasts, primarily occurs through the action of currents and waves but sea level (tidal) change can also play a role. Hydraulic action takes place when the air in a joint is suddenly compressed by

1023-487: A mountain mass similar to the Himalaya into an almost-flat peneplain if there are no significant sea-level changes . Erosion of mountains massifs can create a pattern of equally high summits called summit accordance . It has been argued that extension during post-orogenic collapse is a more effective mechanism of lowering the height of orogenic mountains than erosion. Examples of heavily eroded mountain ranges include

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1116-935: A rate of 30 to 40,000 gallons a day). 50°08′17″N 5°14′38″W  /  50.138°N 5.244°W  / 50.138; -5.244 Tourist attraction Places of natural beauty such as beaches , tropical island resorts , national parks , mountains , deserts and forests , are examples of traditional tourist attractions which people may visit. Cultural tourist attractions can include historical places, sites of significant historic event , monuments , ancient temples , zoos , aquaria , museums and art galleries , botanical gardens , buildings and structures (such as forts , castles , libraries , former prisons , skyscrapers , bridges ), theme parks and carnivals , living history museums , public art ( sculptures , statues , murals ), ethnic enclave communities, historic trains and cultural events. Factory tours, industrial heritage, creative art and crafts workshops are

1209-481: A reasonable admission charge or even for free, others may be of low quality and overprice their goods and services (such as admission, food, and souvenirs) in order to profit excessively from tourists. Such places are commonly known as tourist traps . Within cities, rides on boats and sightseeing buses are sometimes popular. Novelty attractions are oddities such as the " biggest ball of twine " in Cawker City, Kansas ,

1302-732: A supposed UFO crash site near Roswell, New Mexico and the alleged Loch Ness monster sightings in Scotland . Ethnic communities may become tourist attractions, such as Chinatowns in the United States and the black British neighborhood of Brixton in London , England. Tourists also look for special local culinary experiences such as street kitchens in Asian metropolises or the coffeehouse culture in Central Europe . In particular, cultural property and

1395-432: A surface is eroded. Typically, physical erosion proceeds the fastest on steeply sloping surfaces, and rates may also be sensitive to some climatically controlled properties including amounts of water supplied (e.g., by rain), storminess, wind speed, wave fetch , or atmospheric temperature (especially for some ice-related processes). Feedbacks are also possible between rates of erosion and the amount of eroded material that

1488-429: A team of volunteers under the direction of engineer Peter Treloar to erect it at Poldark Mine. By spring 1973 the engine was operating on compressed air. In the 1980s the attraction became known as "Ha'penny Park". Peter and Jose Young retired to Spain and sold Poldark Mine to John McLeod who ran it until it was placed in receivership in 1999. In 2000 the property was purchased by a company set up by Richard Williams who

1581-501: A wave closing the entrance of the joint. This then cracks it. Wave pounding is when the sheer energy of the wave hitting the cliff or rock breaks pieces off. Abrasion or corrasion is caused by waves launching sea load at the cliff. It is the most effective and rapid form of shoreline erosion (not to be confused with corrosion ). Corrosion is the dissolving of rock by carbonic acid in sea water. Limestone cliffs are particularly vulnerable to this kind of erosion. Attrition

1674-412: A weak bedrock (containing material more erodible than the surrounding rocks) erosion pattern, on the contrary, the amount of over deepening is limited because ice velocities and erosion rates are reduced. Glaciers can also cause pieces of bedrock to crack off in the process of plucking. In ice thrusting, the glacier freezes to its bed, then as it surges forward, it moves large sheets of frozen sediment at

1767-662: Is a good example of a region marketed and branded as a place for tourists to visit, mainly known for its Châteaux of the Loire valley . A tropical island resort is an island or archipelago that depends on tourism as its source of revenue. The Bahamas in the Caribbean , Bali in Indonesia , Phuket in Thailand , Hawaii in the United States , Fiji in the Pacific, and Santorini and Ibiza in

1860-537: Is already carried by, for example, a river or glacier. The transport of eroded materials from their original location is followed by deposition, which is arrival and emplacement of material at a new location. While erosion is a natural process, human activities have increased by 10–40 times the rate at which soil erosion is occurring globally. At agriculture sites in the Appalachian Mountains , intensive farming practices have caused erosion at up to 100 times

1953-490: Is also more prone to mudslides, landslides, and other forms of gravitational erosion processes. Tectonic processes control rates and distributions of erosion at the Earth's surface. If the tectonic action causes part of the Earth's surface (e.g., a mountain range) to be raised or lowered relative to surrounding areas, this must necessarily change the gradient of the land surface. Because erosion rates are almost always sensitive to

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2046-484: Is an example of extreme chemical erosion. Glaciers erode predominantly by three different processes: abrasion/scouring, plucking , and ice thrusting. In an abrasion process, debris in the basal ice scrapes along the bed, polishing and gouging the underlying rocks, similar to sandpaper on wood. Scientists have shown that, in addition to the role of temperature played in valley-deepening, other glaciological processes, such as erosion also control cross-valley variations. In

2139-409: Is distinguished from changes on the bed of the watercourse, which is referred to as scour . Erosion and changes in the form of river banks may be measured by inserting metal rods into the bank and marking the position of the bank surface along the rods at different times. Thermal erosion is the result of melting and weakening permafrost due to moving water. It can occur both along rivers and at

2232-602: Is marketed or markets itself as a place for tourists to visit". It may contain one or more tourist attractions and possibly some "tourist traps". Fátima town, for example, is a popular tourist destination in Portugal . Siem Reap town is a popular tourist destination in Cambodia , mainly owing to its proximity to the Angkor temples. The Loire valley , the third tourist destination in France ,

2325-437: Is not enough to prevent destruction, robbery and looting. The founding president of Blue Shield International Karl von Habsburg summed it up with the words: “Without the local community and without the local participants, that would be completely impossible”. Erosion Erosion is the action of surface processes (such as water flow or wind ) that removes soil , rock , or dissolved material from one location on

2418-405: Is of two primary varieties: deflation , where the wind picks up and carries away loose particles; and abrasion , where surfaces are worn down as they are struck by airborne particles carried by wind. Deflation is divided into three categories: (1) surface creep , where larger, heavier particles slide or roll along the ground; (2) saltation , where particles are lifted a short height into

2511-482: Is shown by the Trenear Mortar Stone, near to the entrance of Poldark Mine. It is an outcrop of granite which has at least 17 hollows in its upper face in which tin ore would have been crushed by hand, using stones. Although impossible to date precisely it is believed to have been in use during the later prehistoric period (c.2000BC to 43 AD). It is the only known example of such a mortar in south-west England and

2604-404: Is sparse and soil is dry (and so is more erodible). Other climatic factors such as average temperature and temperature range may also affect erosion, via their effects on vegetation and soil properties. In general, given similar vegetation and ecosystems, areas with more precipitation (especially high-intensity rainfall), more wind, or more storms are expected to have more erosion. In some areas of

2697-457: Is the main climatic factor governing soil erosion by water. The relationship is particularly strong if heavy rainfall occurs at times when, or in locations where, the soil's surface is not well protected by vegetation . This might be during periods when agricultural activities leave the soil bare, or in semi-arid regions where vegetation is naturally sparse. Wind erosion requires strong winds, particularly during times of drought when vegetation

2790-400: Is where particles/sea load carried by the waves are worn down as they hit each other and the cliffs. This then makes the material easier to wash away. The material ends up as shingle and sand. Another significant source of erosion, particularly on carbonate coastlines, is boring, scraping and grinding of organisms, a process termed bioerosion . Sediment is transported along the coast in

2883-634: The Corn Palace in Mitchell, South Dakota , or Carhenge in Alliance, Nebraska , where old cars serve in the place of stones in a replica of Stonehenge . Novelty attractions are not limited to the American Midwest, but are part of Midwestern culture . A tourist destination is a city, town, or other area that is significantly dependent on revenues from tourism, or "a country, state, region, city, or town which

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2976-479: The Duchy of Cornwall . The museum and mine now known as Poldark Mine started in summer 1966 when Peter Young, a Royal Marine , purchased the local smithy, Wendron Forge, in an auction in the hamlet of Trenear , while on weekend leave. Young quickly acquired about three acres of adjoining land which were separated by a large furniture store which was formerly a dairy and originally part of the Wendron Consols mine. He spent

3069-468: The Earth's crust and then transports it to another location where it is deposited . Erosion is distinct from weathering which involves no movement. Removal of rock or soil as clastic sediment is referred to as physical or mechanical erosion; this contrasts with chemical erosion, where soil or rock material is removed from an area by dissolution . Eroded sediment or solutes may be transported just

3162-658: The Great Plains , it is estimated that soil loss due to wind erosion can be as much as 6100 times greater in drought years than in wet years. Mass wasting or mass movement is the downward and outward movement of rock and sediments on a sloped surface, mainly due to the force of gravity . Mass wasting is an important part of the erosional process and is often the first stage in the breakdown and transport of weathered materials in mountainous areas. It moves material from higher elevations to lower elevations where other eroding agents such as streams and glaciers can then pick up

3255-700: The Timanides of Northern Russia. Erosion of this orogen has produced sediments that are now found in the East European Platform , including the Cambrian Sablya Formation near Lake Ladoga . Studies of these sediments indicate that it is likely that the erosion of the orogen began in the Cambrian and then intensified in the Ordovician . If the erosion rate exceeds soil formation , erosion destroys

3348-416: The accumulation zone above the glacial equilibrium line altitude), which causes increased rates of erosion of the mountain, decreasing mass faster than isostatic rebound can add to the mountain. This provides a good example of a negative feedback loop . Ongoing research is showing that while glaciers tend to decrease mountain size, in some areas, glaciers can actually reduce the rate of erosion, acting as

3441-405: The impact of a falling raindrop creates a small crater in the soil , ejecting soil particles. The distance these soil particles travel can be as much as 0.6 m (2.0 ft) vertically and 1.5 m (4.9 ft) horizontally on level ground. If the soil is saturated , or if the rainfall rate is greater than the rate at which water can infiltrate into the soil, surface runoff occurs. If

3534-455: The lower crust and mantle . Because tectonic processes are driven by gradients in the stress field developed in the crust, this unloading can in turn cause tectonic or isostatic uplift in the region. In some cases, it has been hypothesised that these twin feedbacks can act to localize and enhance zones of very rapid exhumation of deep crustal rocks beneath places on the Earth's surface with extremely high erosion rates, for example, beneath

3627-407: The surface runoff which may result from rainfall, produces four main types of soil erosion : splash erosion , sheet erosion , rill erosion , and gully erosion . Splash erosion is generally seen as the first and least severe stage in the soil erosion process, which is followed by sheet erosion, then rill erosion and finally gully erosion (the most severe of the four). In splash erosion ,

3720-457: The 19th century the site was occupied by the main dressing floors of Wendron Consols mine. This was where the tin ore was crushed and purified. When tin prices fell in the late 19th century many mines closed, although there is a record of 1893 indicating that a stream-work was still active at Trenear at that date. The author of the Poldark books Winston Graham gave permission to use the title as

3813-499: The 21st century, a strong link has been drawn between the increase in storm frequency with an increase in sediment load in rivers and reservoirs, highlighting the impacts climate change can have on erosion. Vegetation acts as an interface between the atmosphere and the soil. It increases the permeability of the soil to rainwater, thus decreasing runoff. It shelters the soil from winds, which results in decreased wind erosion, as well as advantageous changes in microclimate. The roots of

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3906-466: The Mediterranean are examples of popular island resorts. France , the United States , and Spain were the three most popular international destinations in 2017. The total number of international travelers arriving in those countries was about 234 million, contributing 8.9%, 7.7%, and 14.9%, respectively, to the total GDP of those countries. Although some years back, Africa was lean on tourism,

3999-472: The United States, owners and marketers of attractions advertise tourist attractions on billboards along the sides of highways and roadways, especially in remote areas. Tourist attractions often distribute free promotional brochures to be displayed in rest areas , information centers, fast food restaurants, and motel rooms or lobbies. While some tourist attractions provide visitors a memorable experience for

4092-433: The air, and bounce and saltate across the surface of the soil; and (3) suspension , where very small and light particles are lifted into the air by the wind, and are often carried for long distances. Saltation is responsible for the majority (50–70%) of wind erosion, followed by suspension (30–40%), and then surface creep (5–25%). Wind erosion is much more severe in arid areas and during times of drought. For example, in

4185-421: The author's personal assessments. Sometimes it is particularly emphasized that this particular tourist attraction has not yet been in the focus of the international tourism industry. Some of the sights are internationally known or target the national or local market. Some attractions are reserved for the local population or are rarely advertised because the main traffic routes and main airports are too far away. In

4278-463: The base along with the glacier. This method produced some of the many thousands of lake basins that dot the edge of the Canadian Shield . Differences in the height of mountain ranges are not only being the result tectonic forces, such as rock uplift, but also local climate variations. Scientists use global analysis of topography to show that glacial erosion controls the maximum height of mountains, as

4371-512: The coast. Rapid river channel migration observed in the Lena River of Siberia is due to thermal erosion, as these portions of the banks are composed of permafrost-cemented non-cohesive materials. Much of this erosion occurs as the weakened banks fail in large slumps. Thermal erosion also affects the Arctic coast , where wave action and near-shore temperatures combine to undercut permafrost bluffs along

4464-409: The coastline. Where there is a bend in the coastline, quite often a buildup of eroded material occurs forming a long narrow bank (a spit ). Armoured beaches and submerged offshore sandbanks may also protect parts of a coastline from erosion. Over the years, as the shoals gradually shift, the erosion may be redirected to attack different parts of the shore. Erosion of a coastal surface, followed by

4557-484: The continent is currently regarded as the second fastest growing tourism region with over 67 million tourists visits to Africa in 2018. Ethiopia , with a growth rate of 48.6% in 2018, is at the top of the list of African tourist centers. Other tourist locations in Africa include Cape Town, South Africa , Giza Necropolis , Egypt , The Maasai Mara National Reserve, Kenya , Victoria Falls , Zimbabwe and Zambia . From

4650-466: The destination and contribute to the overall experience of the trip. The ultimate primary purpose of attractions is to attract the customer's attention so that they can come to a specific location and explore the various attractions on vacation. In the travel and tourism industry, attractions therefore play a particularly important role as this attracts tourists from all over the world. Tourist attractions are also created to capitalize on legends such as

4743-411: The direction of the prevailing current ( longshore drift ). When the upcurrent supply of sediment is less than the amount being carried away, erosion occurs. When the upcurrent amount of sediment is greater, sand or gravel banks will tend to form as a result of deposition . These banks may slowly migrate along the coast in the direction of the longshore drift, alternately protecting and exposing parts of

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4836-563: The event of war, many tourist attractions are a special goal in order to cause lasting damage to the enemy or to finance the war. International attempts are therefore made to protect and preserve these economic and cultural foundations of a community, city or country. There is intensive cooperation between the United Nations , UNESCO and Blue Shield International on the protection of cultural goods and UNESCO World Heritage Sites. However, cooperation between organizations and state authorities

4929-442: The extensive erosion over geological time of a great depth of overlying sedimentary rocks which contained many ore-bearing lodes . Pebbles and grains of the heavy ore collected in the river gravels and sands, eventually leading to the rich tin-bearing grounds that were found near the surface of most of the river valleys flowing from the granite. Evidence that this abundance of ore was first recovered and processed in ancient times

5022-405: The extremely steep terrain of Nanga Parbat in the western Himalayas . Such a place has been called a " tectonic aneurysm ". Human land development, in forms including agricultural and urban development, is considered a significant factor in erosion and sediment transport , which aggravate food insecurity . In Taiwan, increases in sediment load in the northern, central, and southern regions of

5115-575: The flood regions result from glacial Lake Missoula , which created the channeled scablands in the Columbia Basin region of eastern Washington . Wind erosion is a major geomorphological force, especially in arid and semi-arid regions. It is also a major source of land degradation, evaporation, desertification, harmful airborne dust, and crop damage—especially after being increased far above natural rates by human activities such as deforestation , urbanization , and agriculture . Wind erosion

5208-417: The growth of protective vegetation ( rhexistasy ) are a key element of badland formation. Valley or stream erosion occurs with continued water flow along a linear feature. The erosion is both downward , deepening the valley , and headward , extending the valley into the hillside, creating head cuts and steep banks. In the earliest stage of stream erosion, the erosive activity is dominantly vertical,

5301-656: The individual places of the UNESCO World Heritage Site have developed into tourist attractions. If too many tourists frequent individual places, this can lead to environmental pollution and resistance from the local population, such as in Barcelona or Venice. With regard to this whole subject, there are already lists of destinations that are not recommended to tourists. There are innumerable lists and reviews of tourist attractions. Visitor statistics, cultural significance, beauty or age are used and these always reflect

5394-411: The island can be tracked with the timeline of development for each region throughout the 20th century. The intentional removal of soil and rock by humans is a form of erosion that has been named lisasion . Mountain ranges take millions of years to erode to the degree they effectively cease to exist. Scholars Pitman and Golovchenko estimate that it takes probably more than 450 million years to erode

5487-409: The local slope (see above), this will change the rates of erosion in the uplifted area. Active tectonics also brings fresh, unweathered rock towards the surface, where it is exposed to the action of erosion. However, erosion can also affect tectonic processes. The removal by erosion of large amounts of rock from a particular region, and its deposition elsewhere, can result in a lightening of the load on

5580-418: The material and move it to even lower elevations. Mass-wasting processes are always occurring continuously on all slopes; some mass-wasting processes act very slowly; others occur very suddenly, often with disastrous results. Any perceptible down-slope movement of rock or sediment is often referred to in general terms as a landslide . However, landslides can be classified in a much more detailed way that reflects

5673-407: The material has begun to slide downhill. In some cases, the slump is caused by water beneath the slope weakening it. In many cases it is simply the result of poor engineering along highways where it is a regular occurrence. Surface creep is the slow movement of soil and rock debris by gravity which is usually not perceptible except through extended observation. However, the term can also describe

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5766-438: The mechanisms responsible for the movement and the velocity at which the movement occurs. One of the visible topographical manifestations of a very slow form of such activity is a scree slope. Slumping happens on steep hillsides, occurring along distinct fracture zones, often within materials like clay that, once released, may move quite rapidly downhill. They will often show a spoon-shaped isostatic depression , in which

5859-506: The mine as location for a number of scenes for their 1977 series of Poldark . This included some of the underground sequences. In the 1977 television film The Man in the Iron Mask , the title character had his mask made and fitted at Wendron Forge, most other locations being in France. Another, shorter, BBC series Penmarrick was filmed at the mine in 1979. The most recent filming on the site

5952-484: The morphologic impact of glaciations on active orogens, by both influencing their height, and by altering the patterns of erosion during subsequent glacial periods via a link between rock uplift and valley cross-sectional shape. At extremely high flows, kolks , or vortices are formed by large volumes of rapidly rushing water. Kolks cause extreme local erosion, plucking bedrock and creating pothole-type geographical features called rock-cut basins . Examples can be seen in

6045-404: The most erosion occurs during times of flood when more and faster-moving water is available to carry a larger sediment load. In such processes, it is not the water alone that erodes: suspended abrasive particles, pebbles , and boulders can also act erosively as they traverse a surface, in a process known as traction . Bank erosion is the wearing away of the banks of a stream or river. This

6138-443: The name of the mine. He launched some of his books at Poldark Mine, including the last Poldark book in 2002, a year before his death. Actress Angharad Rees , who had the leading role of Demelza in the 1970s BBC TV costume drama Poldark was a regular visitor to the mine and gardens up to the time of her death in 2012. There is a memorial to her at Poldark Mine which was dedicated by her son. The BBC approached Peter Young to use

6231-531: The natural rate of erosion in the region. Excessive (or accelerated) erosion causes both "on-site" and "off-site" problems. On-site impacts include decreases in agricultural productivity and (on natural landscapes ) ecological collapse , both because of loss of the nutrient-rich upper soil layers . In some cases, this leads to desertification . Off-site effects include sedimentation of waterways and eutrophication of water bodies , as well as sediment-related damage to roads and houses. Water and wind erosion are

6324-464: The next few years purchasing and repairing agricultural and industrial machinery, though his intention was to run a business selling etchings that he designed and produced on site. The site was opened to the public in June 1971 as Wendron Forge after the level of the flood-prone ground was raised, facilities were constructed and about six working machines and engines were installed to interest visitors. In 1972

6417-434: The nutrient-rich upper soil layers . In some cases, the eventual result is desertification . Off-site effects include sedimentation of waterways and eutrophication of water bodies, as well as sediment-related damage to roads and houses. Water and wind erosion are the two primary causes of land degradation ; combined, they are responsible for about 84% of the global extent of degraded land , making excessive erosion one of

6510-461: The object of cultural niches like industrial tourism and creative tourism. Many tourist attractions are also landmarks . But sports events such as a soccer game, Formula 1 race or sailing regatta can also attract tourists. Tourists' expectations when visiting a particular place are related to several features of the chosen destination: culture, architecture, gastronomy, infrastructure, landscape, events, shopping, etc. These features attract people to

6603-411: The order of a few centimetres (about an inch) or less and along-channel slopes may be quite steep. This means that rills exhibit hydraulic physics very different from water flowing through the deeper, wider channels of streams and rivers. Gully erosion occurs when runoff water accumulates and rapidly flows in narrow channels during or immediately after heavy rains or melting snow, removing soil to

6696-480: The pipes lifted the water out of the mine. In the mine at Horse Whim Shaft the granite on the side of the shaft has been worn smooth by the rubbing of the kibble against it, this shaft is over 200 feet deep and its further depths remain unexplored. In the Museum a large cast and wrought iron kibble recovered from the main shaft can be seen, it dates from the 18th century when the mine was active in tin production. During

6789-556: The plants bind the soil together, and interweave with other roots, forming a more solid mass that is less susceptible to both water and wind erosion. The removal of vegetation increases the rate of surface erosion. The topography of the land determines the velocity at which surface runoff will flow, which in turn determines the erosivity of the runoff. Longer, steeper slopes (especially those without adequate vegetative cover) are more susceptible to very high rates of erosion during heavy rains than shorter, less steep slopes. Steeper terrain

6882-516: The primary motivations for a region to promote itself as a tourism destination is the expected economic benefit. According to the World Tourism Organization , 698 million people travelled to a foreign country in 2000, spending more than US$ 478 billion. International tourism receipts combined with passenger transport currently total more than US$ 575 billion – making tourism the world's number one export earner. Tourist attractions can: In

6975-764: The property was put up for sale, with a guide price of £350,000. It was purchased by David Edwards who had been involved with the Ffestiniog Railway and the Llechwedd Slate Caverns in Wales, and work to repair and restore the mine commenced immediately: it reopened in May 2014. The site lies in the valley of the River Cober on the Carnmenellis granite outcrop. The river valley was once extremely rich in tin ore because of

7068-413: The relief between mountain peaks and the snow line are generally confined to altitudes less than 1500 m. The erosion caused by glaciers worldwide erodes mountains so effectively that the term glacial buzzsaw has become widely used, which describes the limiting effect of glaciers on the height of mountain ranges. As mountains grow higher, they generally allow for more glacial activity (especially in

7161-828: The rolling of dislodged soil particles 0.5 to 1.0 mm (0.02 to 0.04 in) in diameter by wind along the soil surface. On the continental slope , erosion of the ocean floor to create channels and submarine canyons can result from the rapid downslope flow of sediment gravity flows , bodies of sediment-laden water that move rapidly downslope as turbidity currents . Where erosion by turbidity currents creates oversteepened slopes it can also trigger underwater landslides and debris flows . Turbidity currents can erode channels and canyons into substrates ranging from recently deposited unconsolidated sediments to hard crystalline bedrock. Almost all continental slopes and deep ocean basins display such channels and canyons resulting from sediment gravity flows and submarine canyons act as conduits for

7254-515: The runoff has sufficient flow energy , it will transport loosened soil particles ( sediment ) down the slope. Sheet erosion is the transport of loosened soil particles by overland flow. Rill erosion refers to the development of small, ephemeral concentrated flow paths which function as both sediment source and sediment delivery systems for erosion on hillslopes. Generally, where water erosion rates on disturbed upland areas are greatest, rills are active. Flow depths in rills are typically of

7347-424: The second time in 2014, and in that year was bought by David Edwards who had been involved with the Ffestiniog Railway and the Llechwedd Slate Caverns in Wales. He said he hoped to keep Poldark Mine as an open-air museum and heritage centre. In September 2022, it was reported that the mine had been closed for three years due to Edwards failing to pay rent for the attractions' underground portions, which are owned by

7440-532: The shoreline and cause them to fail. Annual erosion rates along a 100-kilometre (62-mile) segment of the Beaufort Sea shoreline averaged 5.6 metres (18 feet) per year from 1955 to 2002. Most river erosion happens nearer to the mouth of a river. On a river bend, the longest least sharp side has slower moving water. Here deposits build up. On the narrowest sharpest side of the bend, there is faster moving water so this side tends to erode away mostly. Rapid erosion by

7533-593: The soil. Lower rates of erosion can prevent the formation of soil features that take time to develop. Inceptisols develop on eroded landscapes that, if stable, would have supported the formation of more developed Alfisols . While erosion of soils is a natural process, human activities have increased by 10-40 times the rate at which erosion occurs globally. Excessive (or accelerated) erosion causes both "on-site" and "off-site" problems. On-site impacts include decreases in agricultural productivity and (on natural landscapes ) ecological collapse , both because of loss of

7626-433: The terminus or during glacier retreat . The best-developed glacial valley morphology appears to be restricted to landscapes with low rock uplift rates (less than or equal to 2mm per year) and high relief, leading to long-turnover times. Where rock uplift rates exceed 2mm per year, glacial valley morphology has generally been significantly modified in postglacial time. Interplay of glacial erosion and tectonic forcing governs

7719-401: The tourism industry supply perspective, a destination is usually defined by a geo-political boundary, and destination marketing is most commonly funded by governments. From the traveler perspective, a destination might be perceived quite differently. Tourism generates substantial economic benefits for both host countries and tourists' home countries. Especially in developing countries, one of

7812-409: The transfer of sediment from the continents and shallow marine environments to the deep sea. Turbidites , which are the sedimentary deposits resulting from turbidity currents, comprise some of the thickest and largest sedimentary sequences on Earth, indicating that the associated erosional processes must also have played a prominent role in Earth's history. The amount and intensity of precipitation

7905-563: The two primary causes of land degradation ; combined, they are responsible for about 84% of the global extent of degraded land, making excessive erosion one of the most significant environmental problems worldwide. Intensive agriculture , deforestation , roads , anthropogenic climate change and urban sprawl are amongst the most significant human activities in regard to their effect on stimulating erosion. However, there are many prevention and remediation practices that can curtail or limit erosion of vulnerable soils. Rainfall , and

7998-427: The valleys have a typical V-shaped cross-section and the stream gradient is relatively steep. When some base level is reached, the erosive activity switches to lateral erosion, which widens the valley floor and creates a narrow floodplain. The stream gradient becomes nearly flat, and lateral deposition of sediments becomes important as the stream meanders across the valley floor. In all stages of stream erosion, by far

8091-550: The world (e.g. western Europe ), runoff and erosion result from relatively low intensities of stratiform rainfall falling onto the previously saturated soil. In such situations, rainfall amount rather than intensity is the main factor determining the severity of soil erosion by water. According to the climate change projections, erosivity will increase significantly in Europe and soil erosion may increase by 13–22.5% by 2050 In Taiwan , where typhoon frequency increased significantly in

8184-491: The world (e.g. the mid-western US ), rainfall intensity is the primary determinant of erosivity (for a definition of erosivity check, ) with higher intensity rainfall generally resulting in more soil erosion by water. The size and velocity of rain drops is also an important factor. Larger and higher-velocity rain drops have greater kinetic energy , and thus their impact will displace soil particles by larger distances than smaller, slower-moving rain drops. In other regions of

8277-402: Was designated as a scheduled monument in 2009. The first mechanised tin stamping mill in Duchy land , and possibly in the whole of Cornwall, is recorded at Trenere Wolas (present-day Lower Trenear) in a document confirming that it was held by John Trenere, a freeman , in 1493. By 1650 the industrial buildings recorded at Trenere Wolas had expanded to a crazing-mill , two stamping-mills and

8370-507: Was in summer 2014, for the new BBC series of Poldark broadcast in 2015. The mine and its museum are part of the UNESCO Cornwall and West Devon Mining Landscape , a World Heritage Site . As of 2015, Poldark was the only complete tin mine in the UK open to the public for genuine underground tours of an 18th-century mine, and the only mine in Cornwall that pumps water to allow public access (at

8463-596: Was later known as Ha'penny Park . After an ancient tin mine was discovered on the site it was renamed after Winston Graham 's Poldark novels and the BBC television series that was first broadcast in 1975. The mine was researched by A. K. Hamilton Jenkin , an authority on Cornish mining history, who attributed it to Wheal Roots which had been active in the 18th century. The original owner, Peter Young, sold Poldark Mine in 1988 following which it passed through two owners and declined in popularity. It went into administration for

8556-542: Was reported to have "put all of his efforts into developing this into one of the most atmospheric tourist underground mine experiences in Europe". At this time one of the attractions was Evening 'Ghost Tours'; the site was licensed for the holding of civil weddings; and it was twinned with the Llywernog Silver-Lead Mine in Wales. Following Williams' death in 2012, the attraction again declined in popularity until it went into administration in 2014. Early that year

8649-477: Was worked using horses and water wheels to power all the machinery and to pump water from it. In the museum there are the remains of an early 'rag and chain' pump used before the days of steam to raise water from mines and which was found when the mine was rediscovered in the 1970s. The pump consisted of a series of wooden pipes made from tree trunks and through which a large endless chain was pulled. The chain had rags tied to it at intervals which when pulled up through

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