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49-470: This open-pit mine in the western part of the Masa San Dionisio was begun in 1907 after major subsidence in some of the higher-altitude parts of the area two years earlier, caused by the combustion of pyrites in the earlier subterranean mines. The mines were nationalized in 1954 but later sold back to a private company. As of October 2009, the current owner, EMED Tartessus, says they will have

98-480: A century, this was home to many of the miners, first those working in the subterranean mine and then in the Corta Atalaya open pit. The population peaked around 1910: In 1970, La Atalaya had 257 buildings and a population of 823. That year, approval was received to enlarge the pit; in 1971, La Atalaya was destroyed because it was in the path of the mining. La Atalaya was not the only townsite sacrificed to

147-630: A comparative analysis of various land subsidence monitoring techniques. The results indicated that InSAR offered the highest coverage, lowest annual cost per point of information and the highest point density. Additionally, they found that, aside from continuous acquisition systems typically installed in areas with rapid subsidence, InSAR had the highest measurement frequencies. In contrast, leveling, non-permanent GNSS, and non-permanent extensometers generally provided only one or two measurements per year. These methods project future land subsidence trends by extrapolating from existing data, treating subsidence as

196-569: A form of mass wasting. A distinction is then made between mass wasting by subsidence, which involves little horizontal movement, and mass wasting by slope movement. Soil creep is a slow and long term mass movement. The combination of small movements of soil or rock in different directions over time is directed by gravity gradually downslope. The steeper the slope, the faster the creep. The creep makes trees and shrubs curve to maintain their perpendicularity, and they can trigger landslides if they lose their root footing. The surface soil can migrate under

245-459: A function solely of time. The extrapolation can be performed either visually or by fitting appropriate curves. Common functions used for fitting include linear, bilinear, quadratic, and/or exponential models. For example, this method has been successfully applied for predicting mining-induced subsidence. These approaches evaluate land subsidence based on its relationship with one or more influencing factors, such as changes in groundwater levels,

294-443: A large mass of earth and rocks down a hill or a mountainside. Landslides can be further classified by the importance of water in the mass wasting process. In a narrow sense, landslides are rapid movement of large amounts of relatively dry debris down moderate to steep slopes. With increasing water content, the mass wasting takes the form of debris avalanches , then earthflows , then mudflows . Further increase in water content produces

343-424: A new approach for tackling nonlinear problems. It has emerged as a promising method for simulating and predicting land subsidence. 80 (1921-1960) 6.5 (1952-1968) 4 (2003-2010) 100 (1997-2002) Slope movement Mass wasting , also known as mass movement , is a general term for the movement of rock or soil down slopes under the force of gravity . It differs from other processes of erosion in that

392-431: A number of years, a cumulative drying occurs as the tree grows. That can lead to the opposite of subsidence, known as heave or swelling of the soil, when the tree declines or is felled. As the cumulative moisture deficit is reversed, which can last up to 25 years, the surface level around the tree will rise and expand laterally. That often damages buildings unless the foundations have been strengthened or designed to cope with

441-489: A result of increased effective stress . In this way, land subsidence has the potential of becoming self-perpetuating, having rates up to 5 cm/yr. Water management used to be tuned primarily to factors such as crop optimization but, to varying extents, avoiding subsidence has come to be taken into account as well. When differential stresses exist in the Earth, these can be accommodated either by geological faulting in

490-425: A sheetflood, which is a form of sheet erosion rather than mass wasting. On Earth , mass wasting occurs on both terrestrial and submarine slopes. Submarine mass wasting is particularly common along glaciated coastlines where glaciers are retreating and great quantities of sediments are being released. Submarine slides can transport huge volumes of sediments for hundreds of kilometers in a few hours. Mass wasting

539-555: A solidified crust of rock; mining; pumping of subsurface fluids, such as groundwater or petroleum ; or warping of the Earth's crust by tectonic forces. Subsidence resulting from tectonic deformation of the crust is known as tectonic subsidence and can create accommodation for sediments to accumulate and eventually lithify into sedimentary rock . Ground subsidence is of global concern to geologists , geotechnical engineers , surveyors , engineers , urban planners , landowners, and

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588-417: A very muddy stream (stream erosion), without a sharp dividing line. Many forms of mass wasting are recognized, each with its own characteristic features, and taking place over timescales from seconds to hundreds of years. Based on how the soil, regolith or rock moves downslope as a whole, mass movements can be broadly classified as either creeps or landslides . Subsidence is sometimes also regarded as

637-431: Is rock glaciers , which form from rockfall from cliffs oversteepened by glaciers. Landslides can produce scarps and step-like small terraces. Landslide deposits are poorly sorted . Those rich in clay may show stretched clay lumps (a phenomenon called boudinage ) and zones of concentrated shear. Debris flow deposits take the form of long, narrow tracks of very poorly sorted material. These may have natural levees at

686-684: Is a common phenomenon throughout the Solar System, occurring where volatile materials are lost from a regolith . Such mass wasting has been observed on Mars , Io , Triton , and possibly Europa and Ganymede . Mass wasting also occurs in the equatorial regions of Mars, where stopes of soft sulfate -rich sediments are steepened by wind erosion. Mass wasting on Venus is associated with the rugged terrain of tesserae . Io shows extensive mass wasting of its volcanic mountains. Mass wasting affects geomorphology , most often in subtle, small-scale ways, but occasionally more spectacularly. Soil creep

735-419: Is a general term for any process of erosion that is driven by gravity and in which the transported soil and rock is not entrained in a moving medium, such as water, wind, or ice. The presence of water usually aids mass wasting, but the water is not abundant enough to be regarded as a transporting medium. Thus, the distinction between mass wasting and stream erosion lies between a mudflow (mass wasting) and

784-427: Is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope movement . Processes that lead to subsidence include dissolution of underlying carbonate rock by groundwater ; gradual compaction of sediments ; withdrawal of fluid lava from beneath

833-456: Is rarely apparent but can produce such subtle effects as curved forest growth and tilted fences and telephone poles. It occasionally produces low scarps and shallow depressions. Solifluction produced lobed or sheetlike deposits, with fairly definite edges, in which clasts (rock fragments) are oriented perpendicular to the contours of the deposit. Rockfall can produce talus slopes at the feet of cliffs. A more dramatic manifestation of rockfall

882-451: Is relatively predictable in its magnitude, manifestation and extent, except where a sudden pillar or near-surface tunnel collapse occurs (usually very old workings ). Mining-induced subsidence is nearly always very localized to the surface above the mined area, plus a margin around the outside. The vertical magnitude of the subsidence itself typically does not cause problems, except in the case of drainage (including natural drainage)–rather, it

931-415: Is the associated surface compressive and tensile strains, curvature, tilts and horizontal displacement that are the cause of the worst damage to the natural environment, buildings and infrastructure. Where mining activity is planned, mining-induced subsidence can be successfully managed if there is co-operation from all of the stakeholders. This is accomplished through a combination of careful mine planning,

980-629: The Gaillard Cut of the Panama Canal accounted for 55,860,400 cubic meters (73,062,600 cu yd) of the 128,648,530 cubic meters (168,265,924 cu yd) of material removed while excavating the cut. Rockslides or landslides can have disastrous consequences, both immediate and delayed. The Oso disaster of March 2014 was a landslide that caused 43 fatalities in Oso, Washington , US. Delayed consequences of landslides can arise from

1029-736: The Solar System . Subsidence is sometimes regarded as a form of mass wasting. A distinction is then made between mass wasting by subsidence, which involves little horizontal movement, and mass wasting by slope movement . Rapid mass wasting events, such as landslides, can be deadly and destructive. More gradual mass wasting, such as soil creep, poses challenges to civil engineering , as creep can deform roadways and structures and break pipelines. Mitigation methods include slope stabilization , construction of walls, catchment dams, or other structures to contain rockfall or debris flows, afforestation , or improved drainage of source areas. Mass wasting

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1078-401: The Corta Atalaya open-pit mine. In 1873, Rio Tinto Company, later Rio Tinto Group , acquired the mines of Riotinto. Encountering the problem of transporting miners from their homes to their workplaces, and taking only economic concerns into consideration, they planned construction of houses where the miners had already built huts to stay overnight near the mines. Thus, the village of La Atalaya

1127-473: The North Lode Golf Club, founded in 1890, it was Spain's oldest, but was abandoned to the growth of the Corta Atalaya pit. It reopened in 1992 under its current name and configuration. The following images help to give a sense of the scale of the mine. 37°42′12″N 6°36′10″W  /  37.70333°N 6.60278°W  / 37.70333; -6.60278 Subsidence Subsidence

1176-409: The area. The subsidence was brought to a halt when secondary recovery wells pumped enough water into the oil reservoir to stabilize it. Land subsidence can occur in various ways during an earthquake. Large areas of land can subside drastically during an earthquake because of offset along fault lines. Land subsidence can also occur as a result of settling and compacting of unconsolidated sediment from

1225-422: The asthenosphere. If mass is added to a local area of the crust (e.g., through deposition ), the crust subsides to compensate and maintain isostatic balance . The opposite of isostatic subsidence is known as isostatic rebound —the action of the crust returning (sometimes over periods of thousands of years) to a state of isostacy, such as after the melting of large ice sheets or the drying-up of large lakes after

1274-401: The brittle crust , or by ductile flow in the hotter and more fluid mantle . Where faults occur, absolute subsidence may occur in the hanging wall of normal faults. In reverse, or thrust, faults, relative subsidence may be measured in the footwall. The crust floats buoyantly in the asthenosphere , with a ratio of mass below the "surface" in proportion to its own density and the density of

1323-481: The debris transported by mass wasting is not entrained in a moving medium, such as water, wind, or ice. Types of mass wasting include creep , solifluction , rockfalls , debris flows , and landslides , each with its own characteristic features, and taking place over timescales from seconds to hundreds of years. Mass wasting occurs on both terrestrial and submarine slopes, and has been observed on Earth , Mars , Venus , Jupiter's moon Io , and on many other bodies in

1372-507: The effect. High buildings can create land subsidence by pressing the soil beneath with their weight. The problem is already felt in New York City , San Francisco Bay Area , Lagos . Land subsidence leads to the lowering of the ground surface, altering the topography. This elevation reduction increases the risk of flooding , particularly in river flood plains and delta areas. Earth fissures are linear fractures that appear on

1421-534: The end of 2010. Two films have used the former mine as a locale: El corazón de la tierra , directed by Antonio Cuadri and based on the novel of the same name by Juan Cobos Wilkins , a political-historical film about the Rio Tinto mines; and the science fiction film Proxima , written and directed by Carlos Atanes , which used the mine as an otherworldly landscape. The nearby golf course Club de Golf Atalaya has grass only on its putting greens . Originally

1470-673: The excessive extraction of groundwater, making it a growing problem throughout the world. Groundwater fluctuations can also indirectly affect the decay of organic material. The habitation of lowlands , such as coastal or delta plains, requires drainage . The resulting aeration of the soil leads to the oxidation of its organic components, such as peat , and this decomposition process may cause significant land subsidence. This applies especially when groundwater levels are periodically adapted to subsidence, in order to maintain desired unsaturated zone depths, exposing more and more peat to oxygen. In addition to this, drained soils consolidate as

1519-706: The formation of landslide dams , as at Thistle, Utah , in April 1983. Volcano flanks can become over-steep resulting in instability and mass wasting. This is now a recognised part of the growth of all active volcanoes. It is seen on submarine volcanoes as well as surface volcanoes: Kamaʻehuakanaloa (formerly Loihi) in the Hawaiian–Emperor seamount chain and Kick 'em Jenny in the Lesser Antilles Volcanic Arc are two submarine volcanoes that are known to undergo mass wasting. The failure of

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1568-521: The ground level. Since exploitation of the Slochteren ( Netherlands ) gas field started in the late 1960s the ground level over a 250 km area has dropped by a current maximum of 30 cm. Extraction of petroleum likewise can cause significant subsidence. The city of Long Beach, California , has experienced 9 meters (30 ft) over the course of 34 years of petroleum extraction, resulting in damage of over $ 100 million to infrastructure in

1617-455: The influence of cycles of freezing and thawing, or hot and cold temperatures, inching its way towards the bottom of the slope forming terracettes . Landslides are often preceded by soil creep accompanied with soil sloughing —loose soil that falls and accumulates at the base of the steepest creep sections. Solifluction is a form of creep characteristics of arctic or alpine climates. It takes place in soil saturated with moisture that thaws during

1666-402: The land surface, characterized by openings or offsets. These fissures can be several meters deep, several meters wide, and extend for several kilometers. They form when the deformation of an aquifer, caused by pumping, concentrates stress in the sediment. This inhomogeneous deformation results in the differential compaction of the sediments. Ground fissures develop when this tensile stress exceeds

1715-443: The last ice age. Lake Bonneville is a famous example of isostatic rebound. Due to the weight of the water once held in the lake, the earth's crust subsided nearly 200 feet (61 m) to maintain equilibrium. When the lake dried up, the crust rebounded. Today at Lake Bonneville , the center of the former lake is about 200 feet (61 m) higher than the former lake edges. Many soils contain significant proportions of clay. Because of

1764-545: The mine operating again before the end of 2013. Corta Atalaya is a mine in western part of the Iberian Pyrite Belt . It is part of a zone of volcanogenic massive sulfide ore deposits of Silurian to Carboniferous age which has produced significant copper, zinc, lead, gold and silver. The village of La Atalaya was constructed for the subterranean mining of the San Dionisio seam , which in 1907 became

1813-420: The mine. Earlier, the original location of Minas de Riotinto lay in the path of the mine; the town was moved to its present site. As of 2008, EMED Mining owns 100% of the mine, through its 100%-owned subsidiary, EMED Tartessus SL. EMED Tartessus is currently tasked with cleaning and restarting the mine, and Proyecto de Rio Tinto to operate it for the long term. For some time after the mine closed in 1992, it

1862-556: The public in general. Pumping of groundwater or petroleum has led to subsidence of as much as 9 meters (30 ft) in many locations around the world and incurring costs measured in hundreds of millions of US dollars. Land subsidence caused by groundwater withdrawal will likely increase in occurrence and related damages, primarily due to global population and economic growth, which will continue to drive higher groundwater demand. Subsidence frequently causes major problems in karst terrains, where dissolution of limestone by fluid flow in

1911-525: The shaking of an earthquake. The Geospatial Information Authority of Japan reported immediate subsidence caused by the 2011 Tōhoku earthquake . In Northern Japan, subsidence of 0.50 m (1.64 ft) was observed on the coast of the Pacific Ocean in Miyako , Tōhoku , while Rikuzentakata, Iwate measured 0.84 m (2.75 ft). In the south at Sōma, Fukushima , 0.29 m (0.95 ft)

1960-573: The sides of the tracks, and sometimes consist of lenses of rock fragments alternating with lenses of fine-grained earthy material. Debris flows often form much of the upper slopes of alluvial fans . Triggers for mass wasting can be divided into passive and activating (initiating) causes. Passive causes include: Activating causes include: Mass wasting causes problems for civil engineering , particularly highway construction . It can displace roads, buildings, and other construction and can break pipelines. Historically, mitigation of landslide hazards on

2009-620: The subsurface creates voids (i.e., caves ). If the roof of a void becomes too weak, it can collapse and the overlying rock and earth will fall into the space, causing subsidence at the surface. This type of subsidence can cause sinkholes which can be many hundreds of meters deep. Several types of sub-surface mining , and specifically methods which intentionally cause the extracted void to collapse (such as pillar extraction, longwall mining and any metalliferous mining method which uses "caving" such as "block caving" or "sub-level caving") will result in surface subsidence. Mining-induced subsidence

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2058-409: The summer months to creep downhill. It takes place on moderate slopes, relatively free of vegetation, that are underlain by permafrost and receive a constant supply of new debris by weathering . Solifluction affects the entire slope rather than being confined to channels and can produce terrace-like landforms or stone rivers . A landslide, also called a landslip, is a relatively rapid movement of

2107-405: The taking of preventive measures, and the carrying out of repairs post-mining. If natural gas is extracted from a natural gas field the initial pressure (up to 60 MPa (600 bar )) in the field will drop over the years. The pressure helps support the soil layers above the field. If the gas is extracted, the overburden pressure sediment compacts and may lead to earthquakes and subsidence at

2156-595: The tensile strength of the sediment. Land subsidence can lead to differential settlements in buildings and other infrastructures , causing angular distortions. When these angular distortions exceed certain values, the structures can become damaged, resulting in issues such as tilting or cracking. Land subsidence causes vertical displacements (subsidence or uplift). Although horizontal displacements also occur, they are generally less significant. The following are field methods used to measure vertical and horizontal displacements in subsiding areas: Tomás et al. conducted

2205-441: The very small particle size, they are affected by changes in soil moisture content. Seasonal drying of the soil results in a lowering of both the volume and the surface of the soil. If building foundations are above the level reached by seasonal drying, they move, possibly resulting in damage to the building in the form of tapering cracks. Trees and other vegetation can have a significant local effect on seasonal drying of soils. Over

2254-665: The volume of groundwater extraction , and clay content. This model assumes that changes in piezometric levels affecting aquifers and aquitards occur only in the vertical direction. It allows for subsidence calculations at a specific point using only vertical soil parameters. Quasi-three-dimensional seepage models apply Terzaghi 's one-dimensional consolidation equation to estimate subsidence, integrating some aspects of three-dimensional effects. The fully coupled three-dimensional model simulates water flow in three dimensions and calculates subsidence using Biot's three-dimensional consolidation theory. Machine learning has become

2303-435: Was founded in 1883. The company simply substituted more durable buildings for the huts, constructing neighborhoods in the locations the miners had already chosen. Construction began on 100 houses, each of 45 square metres (480 sq ft), providing only the most minimal necessities of lodging. The company then went on to build a public plaza, chapel, grocery store, casino, school, and a Guardia Civil barracks. For almost

2352-672: Was observed. The maximum amount of subsidence was 1.2 m (3.93 ft), coupled with horizontal diastrophism of up to 5.3 m (17.3 ft) on the Oshika Peninsula in Miyagi Prefecture . Groundwater-related subsidence is the subsidence (or the sinking) of land resulting from groundwater extraction. It is a growing problem in the developing world as cities increase in population and water use, without adequate pumping regulation and enforcement. One estimate has 80% of serious land subsidence problems associated with

2401-534: Was possible to visit the mine. EMED Tartessus did not allow the public to visit as of 2007, but was discussing the possibility of changing that. EMED projects that eventually the mine will again employ 450 people, and that they will be spending over €130 million per year in Spain. As of September 2007, they had spent €3.5 million and budgeted another €15 million toward cleanup and resumption of operations. As of 26 October 2009, they projected that production would resume by

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