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28-601: The plateau to the west of the range is drained by tributaries of the Uruguay River , including the Pelotas and Canoas , and by the Jacuí River and its tributaries, which drains south into the Lagoa dos Patos of Rio Grande do Sul. The Serra Geral is home to Aparados da Serra National Park and Serra Geral National Park , which are notable for their enormous canyons. The plateau is

56-655: A diplomatic crisis , compelling one of the companies move the project 250 kilometres (160 mi) south. Beginning in December 2005, the international bridges linking the Argentine province of Entre Ríos with Uruguay were intermittently blockaded by Argentine protesters, causing major disruptions in commercial traffic and tourism. In 2006, Argentina brought the dispute before the International Court of Justice . The ICJ completed hearings between Argentina and Uruguay regarding

84-484: A conflict over the construction of pulp mills on the Uruguay River. Two European companies, ENCE and Botnia, proposed building cellulose processing plants at Fray Bentos , Uruguay, opposite Gualeguaychú , Argentina. According to a 1975 treaty, Argentina and Uruguay were supposed to jointly agree on matters relating to the Uruguay River. Argentina alleged that Uruguay broke the treaty. Additionally, Argentina believed

112-458: A hillslope) observed in submarine canyons. Mass wasting is the term used for the slower and smaller action of material moving downhill. Slumping is generally used for rotational movement of masses on a hillside. Landslides, or slides, generally comprise the detachment and displacement of sediment masses. It is now understood that many mechanisms of submarine canyon creation have had effect to greater or lesser degree in different places, even within

140-426: A sea with a bed significantly below sea level is cut off from the larger ocean to which it is usually connected. The sea which is normally repleted by contact and inflow from the ocean is now no longer replenished and hence dries up over a period of time, which can be very short if the local climate is arid. In this scenario, rivers that previously flowed into the sea at a sea level elevation now can cut far deeper into

168-588: Is a major river in South America . It flows from north to south and forms parts of the boundaries of Brazil , Argentina and Uruguay , separating some of the Argentine provinces of La Mesopotamia from the other two countries. It passes between the states of Santa Catarina and Rio Grande do Sul in Brazil; forms the eastern border of the provinces of Misiones , Corrientes and Entre Ríos in Argentina; and makes up

196-492: Is a steep-sided valley cut into the seabed of the continental slope , sometimes extending well onto the continental shelf , having nearly vertical walls, and occasionally having canyon wall heights of up to 5 km (3 mi), from canyon floor to canyon rim, as with the Great Bahama Canyon . Just as above-sea-level canyons serve as channels for the flow of water across land, submarine canyons serve as channels for

224-500: Is crossed by five international bridges called (from north to south): Integration Bridge and Paso de los Libres-Uruguaiana International Bridge , between Argentina and Brazil; and the Salto Grande Bridge , General Artigas Bridge and Libertador General San Martín Bridge between Argentina and Uruguay . The drainage basin of the Uruguay River has an area of 365,000 km (141,000 sq mi). Its main economic use

252-563: Is the generation of hydroelectricity and it is dammed in its lower portion by the Salto Grande Dam and by the Itá Dam upstream in Brazil. Uruguay River at Salto Grande : Mean annual discharge at mouth: 217 km /a (6,900 m /s)–228 km /a (7,200 m /s) The main tributaries from the mouth: tributary tributary (km) (km ) (m /s) Yabotí Guazú Antes Period: 1971–2000 Argentina and Uruguay experienced

280-716: The Paraná River , the Uruguay forms the Río de la Plata estuary . It is navigable from around Salto Chico . Its main tributary is the Río Negro , which is born in the south of Brazil and goes through Uruguay for 500 km until its confluence with the Uruguay River, which is located 100 km north of the Uruguay's confluence with the Río de la Plata, in Punta Gorda, Colonia Department , Uruguay. The river

308-671: The Serra do Mar in Brazil , where the Canoas River and the Pelotas River are joined, at about 200 metres (660 ft) above mean sea level . At this stage, the river goes through uneven, broken terrain, forming rapids and falls. Its course through Rio Grande do Sul is not navigable. An unusual feature of the Uruguay River is a submerged canyon . This canyon formed during the Ice Age , when

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336-524: The abyssal plain , where the particles settle out. About 3% of submarine canyons include shelf valleys that have cut transversely across continental shelves, and which begin with their upstream ends in alignment with and sometimes within the mouths of large rivers , such as the Congo River and the Hudson Canyon . About 28.5% of submarine canyons cut back into the edge of the continental shelf, whereas

364-592: The early Cretaceous , and which has matching segments in Angola and Namibia in Africa. 29°08′03″S 49°59′41″W  /  29.13417°S 49.99466°W  / -29.13417; -49.99466 This geographical article relating to Rio Grande do Sul is a stub . You can help Misplaced Pages by expanding it . Uruguay River The Uruguay River ( Spanish : Río Uruguay [ˈri.o wɾuˈɣwaj] ; Portuguese : Rio Uruguai [ˈʁi.u uɾuˈɡwaj] )

392-444: The water depths as great as 3,000 meters (9,800 ft) where canyons have been mapped, as it is well established (by many lines of evidence) that sea levels did not fall to those depths. The major mechanism of canyon erosion is thought to be turbidity currents and underwater landslides . Turbidity currents are dense , sediment-laden currents which flow downslope when an unstable mass of sediment that has been rapidly deposited on

420-502: The Finnish company Botnia was polluting the fish and the overall environment of the river while Uruguay believed that the plant was not depositing a large amount of toxins in the Uruguay River. Starting in April 2005, residents of Gualeguaychú, as well as many others, protested, claiming that the plants would pollute the river shared by the two countries. Early in 2006, the conflict escalated into

448-519: The Moconá Falls are parallel to the river, not perpendicular . The falls are 10 metres (33 ft) to 12 metres (39 ft) high and between 1,800 metres (5,900 ft) and 3,000 metres (9,800 ft) wide. They are 1,215 km (755 mi) from the mouth of the river. The 17,491 ha (43,220 acres) Turvo State Park , created in 1947, protects the Brazilian side of the falls. Together with

476-830: The abyssal plain. Ancient examples have been found in rocks dating back to the Neoproterozoic . Turbidites are deposited at the downstream mouths or ends of canyons, building an abyssal fan . Submarine canyons are more common on the steep slopes found on active margins compared to those on the gentler slopes found on passive margins . They show erosion through all substrates, from unlithified sediment to crystalline rock . Canyons are steeper, shorter, more dendritic and more closely spaced on active than on passive continental margins. The walls are generally very steep and can be near vertical. The walls are subject to erosion by bioerosion , or slumping . There are an estimated 9,477 submarine canyons on Earth, covering about 11% of

504-576: The bottom of the bed now exposed. The Messinian salinity crisis is an example of this phenomenon; between five and six million years ago, the Mediterranean Sea became isolated from the Atlantic Ocean and evaporated away in roughly a thousand years. During this time, the Nile River delta, among other rivers, extended far beyond its present location, both in depth and length. In a cataclysmic event,

532-476: The climate was drier and the river was narrower. Its depth is up to 100 metres (330 ft) below the bottom of the river channel and it is 1/8 to 1/3 as wide as the river. The canyon is only visible in two places, one of which is the Moconá Falls (also called the Yucumã Falls). However, the falls are not visible for 150 days per year and become more like rapids when they are not visible. Unlike most waterfalls ,

560-507: The coldest part of Brazil, with frequent frosts and yearly snow , being home to the montane Araucaria moist forests . It is on Santa Catarina's portion of the Serra Geral where Brazil's coldest towns, Urubici , Urupema , São Joaquim and Bom Jardim da Serra , are located. The mountains and plateau are mainly basalt , formed as part of the Paraná large igneous province which erupted in

588-541: The continental slope. Different mechanisms have been proposed for the formation of submarine canyons. Their primary causes have been subject to debate since the early 1930s. An early and obvious theory was that the canyons present today were carved during glacial times, when sea level was about 125 meters (410 ft) below present sea level, and rivers flowed to the edge of the continental shelf. However, while many (but not all) canyons are found offshore from major rivers, subaerial river erosion cannot have been active to

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616-427: The continental slope. While at first glance the erosion patterns of submarine canyons may appear to mimic those of river-canyons on land, several markedly different processes have been found to take place at the soil/water interface. Many canyons have been found at depths greater than 2 km (1 mi) below sea level . Some may extend seawards across continental shelves for hundreds of kilometres before reaching

644-547: The dispute on October 2, 2009. In 2010, the court ruled that although Uruguay failed to inform Argentina of the construction of the pulp mills, the mills did not pollute the river, so closing the remaining pulp mill would be unjustified. Later in 2010, Argentina and Uruguay created a joint commission to coordinate activities on the river. The course of the Uruguay is crossed by the following bridges, beginning upstream: [REDACTED] Media related to Uruguay River at Wikimedia Commons Submarine canyon A submarine canyon

672-407: The flow of turbidity currents across the seafloor. Turbidity currents are flows of dense, sediment laden waters that are supplied by rivers, or generated on the seabed by storms, submarine landslides, earthquakes, and other soil disturbances. Turbidity currents travel down slope at great speed (as much as 70 km/h (43 mph)), eroding the continental slope and finally depositing sediment onto

700-415: The majority (about 68.5%) of submarine canyons have not managed at all to cut significantly across their continental shelves, having their upstream beginnings or "heads" on the continental slope, below the edge of continental shelves. The formation of submarine canyons is believed to occur as the result of at least two main process: 1) erosion by turbidity current erosion; and 2) slumping and mass wasting of

728-507: The same canyon, or at different times during a canyon's development. However, if a primary mechanism must be selected, the downslope lineal morphology of canyons and channels and the transportation of excavated or loose materials of the continental slope over extensive distances require that various kinds of turbidity or density currents act as major participants. In addition to the processes described above, submarine canyons that are especially deep may form by another method. In certain cases,

756-471: The upper slope fails, perhaps triggered by earthquakes. There is a spectrum of turbidity- or density-current types ranging from " muddy water" to massive mudflow, and evidence of both these end members can be observed in deposits associated with the deeper parts of submarine canyons and channels, such as lobate deposits (mudflow) and levees along channels. Mass wasting , slumping, and submarine landslides are forms of slope failures (the effect of gravity on

784-640: The western borders of the departments of Artigas , Salto , Paysandú , Río Negro , Soriano and Colonia in Uruguay. The name of the river tends to comes from the Spanish settlers' interpretation of the Guaraní language word the inhabitants of the region used to designate it. There are several interpretations, including "the river of the uru (an indigenous bird)", and "[river of] the uruguá" (an indigenous gastropod , Pomella megastoma ). The river measures about 1,838 km (1,142 mi) in length and starts in

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