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49-581: The Paraná River , from which the Paraná Basin derived its name, flows along the central axis of the Paraná Basin and drains it. The Paraná Basin stretches from the Brazilian state of Mato Grosso in the north to northern Argentina and Uruguay in the south. The southern portion in Uruguay is locally known as Norte Basin. The first study on the Brazilian side of the Paraná Basin dates from 1841, when

98-465: A Brazilian Imperial Government Mission prospected for coal . Turning point in the basin's geological understanding was the "White Report", published in 1908 by the American geologist Israel C. White , head of the "Comissão de Estudos das Minas de Carvão de Pedra do Brasil" (Commission for Studies on Brazilian Coal Mines). One of the main results of these studies, besides the reconnaissance for coal,

147-480: A thin section using a method like the Gazzi-Dickinson Method . This yields the relative percentages of quartz, feldspar, and lithic grains and the amount of clay matrix. The composition of a sandstone can provide important information on the genesis of the sediments when used with a triangular Q uartz, F eldspar, L ithic fragment ( QFL diagrams ). However, geologist have not been able to agree on

196-427: A joint project between Paraguay and Argentina. The massive reservoir formed by the project has been the source of a number of problems for people living along the river, most notably the poorer merchants and residents in the low-lying areas of Encarnación, a major city on the southern border of Paraguay. River levels rose dramatically upon completion of the dam, flooding out large sections of the city's lower areas. From

245-478: A sandstone goes through as the degree of kinetic processing of the sediments increases. Dott's (1964) sandstone classification scheme is one of many such schemes used by geologists for classifying sandstones. Dott's scheme is a modification of Gilbert's classification of silicate sandstones, and it incorporates R.L. Folk's dual textural and compositional maturity concepts into one classification system. The philosophy behind combining Gilbert's and R. L. Folk's schemes

294-619: A series of seven cascades. This natural feature was said to rival the world-famous Iguazu Falls to the south. The falls were flooded, however, by the construction of the Itaipu Dam , which began operating in 1984. For approximately the next 200 km (120 mi), the Paraná flows southward and forms a natural boundary between Paraguay and Brazil until the confluence with the Iguazu River . Further upstream from this confluence, however,

343-462: A set of boundaries separating regions of the QFL triangle. Visual aids are diagrams that allow geologists to interpret different characteristics of a sandstone. For example, a QFL chart can be marked with a provenance model that shows the likely tectonic origin of sandstones with various compositions of framework grains. Likewise, the stage of textural maturity chart illustrates the different stages that

392-445: A twofold classification: Cement is what binds the siliciclastic framework grains together. Cement is a secondary mineral that forms after deposition and during burial of the sandstone. These cementing materials may be either silicate minerals or non-silicate minerals, such as calcite. Sandstone that becomes depleted of its cement binder through weathering gradually becomes friable and unstable. This process can be somewhat reversed by

441-837: Is a distinction that can be recognized in the field . In turn, the distinction between an orthoquartzite and a metaquartzite is the onset of recrystallization of existing grains. The dividing line may be placed at the point where strained quartz grains begin to be replaced by new, unstrained, small quartz grains, producing a mortar texture that can be identified in thin sections under a polarizing microscope. With increasing grade of metamorphism, further recrystallization produces foam texture , characterized by polygonal grains meeting at triple junctions, and then porphyroblastic texture , characterized by coarse, irregular grains, including some larger grains ( porphyroblasts .) Sandstone has been used since prehistoric times for construction, decorative art works and tools. It has been widely employed around

490-697: Is a river in south-central South America, running through Brazil, Paraguay, and Argentina for some 4,880 kilometres (3,030 mi). Among South American rivers, it is second in length only to the Amazon River . It merges with the Paraguay River and then farther downstream with the Uruguay River to form the Río de la Plata and empties into the Atlantic Ocean. The first European to go up

539-523: Is likely formed during eogenesis. Deeper burial is accompanied by mesogenesis , during which most of the compaction and lithification takes place. Compaction takes place as the sand comes under increasing pressure from overlying sediments. Sediment grains move into more compact arrangements, ductile grains (such as mica grains) are deformed, and pore space is reduced. In addition to this physical compaction, chemical compaction may take place via pressure solution . Points of contact between grains are under

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588-1231: Is one of the world's largest aquifer systems and an important source of fresh water in Argentina , Brazil, Paraguay and Uruguay . The lithology of the Aquifer consists mainly of highly permeable sandstones of the Botucatu and Pirambóia formations. The aquifer covers 1,200,000 km (460,000 sq mi) with an estimated volume of about 37,000 km (3.0 × 10 acre⋅ft) of water.       De Santa Ana, Héctor; Goso Aguilar, César; Montaño, Jorge; Piñeiro, Graciela; Muzio, Rossana; Rossello, Eduardo; Perea, Daniel; Ucha, Nelson (2004). Cuencas sedimentarias de Uruguay - geología, paleontología y recursos naturales - Mesozóico (PDF) . División Relaciones y Actividades Culturales de Facultad de Ciencias . pp. 1–219 . Retrieved 2017-09-11 . Paran%C3%A1 River (Period: 1971–2000)667 km /a (21,100 m /s) The Paraná River ( Portuguese : Rio Paraná [ˈʁi.u paɾaˈna] ; Spanish: Río Paraná [ˈri.o paɾaˈna] ; Guarani : Ysyry Parana )

637-896: Is overlain by the Huayquerian Ituzaingó Formation that underlies the Pleistocene Toropí and Yupoí Formations . Older Neogene formations in the basin comprise the Late Miocene Paraná Formation . The Uruguayan part of the basin contains the Late Pleistocene ( Lujanian ) Dolores and Sopas Formations and the Brazilian portion hosts the Lujanian Touro Passo Formation . The main natural resources extracted in Paraná Basin are groundwater , coal and oil shale . The Guaraní Aquifer

686-431: Is redeposited in the unstrained pore spaces. Mechanical compaction takes place primarily at depths less than 1,000 meters (3,300 ft). Chemical compaction continues to depths of 2,000 meters (6,600 ft), and most cementation takes place at depths of 2,000–5,000 meters (6,600–16,400 ft). Unroofing of buried sandstone is accompanied by telogenesis , the third and final stage of diagenesis. As erosion reduces

735-592: Is represented, at the base, by sheet-like, cross-bedded coarse to medium sandstones of the Furnas Formation and, on top, by a muddy section, rich in macrofossils and forming a potential petroleum source rock , named Ponta Grossa Formation . The Carboniferous to Early Triassic Gondwana I Supersequence has two distinctive features: Finally, during the Late Permian the Irati Formation

784-443: Is that it is better able to "portray the continuous nature of textural variation from mudstone to arenite and from stable to unstable grain composition". Dott's classification scheme is based on the mineralogy of framework grains, and on the type of matrix present in between the framework grains. In this specific classification scheme, Dott has set the boundary between arenite and wackes at 15% matrix. In addition, Dott also breaks up

833-589: The Asunción arch , a forebulge , to develop in Paraguay. The Asunción arch makes up the modern western boundary of Paraná Basin. The sedimentary column of the Paraná Basin was divided by Milani in 1997, into six second order allostratigraphic supersequences (in the sense of Vail, 1977). These sequences define the stratigraphic framework of the basin and are bound by distinct depositional hiati, caused by erosive events. The basal supersequence, deposited during

882-672: The Ordovician right up to the Cretaceous , thus spanning the time interval between 460 and 66 million years. The maximum thickness of the infill reaches 7,000 metres (23,000 ft) in its central area and is composed of sedimentary and igneous rocks. The sedimentary cover extends across various Precambrian geologic provinces: the Río de la Plata Craton , the Mantiqueira Province , the Luis Alves craton fragment ,

931-588: The Tocantins Province and the Paranapanema block . This last province is distinct in that it is wholly covered by basin sediments and therefore poorly known. The Paraná Basin is a typical intra-cratonic flexural basin, although during the Paleozoic it was a gulf that opened to the southwest. The basin genesis is related to the convergence between the former Gondwana supercontinent and

980-783: The oceanic crust of the former Panthalassa ocean. The basin formed, at least during the Paleozoic Gondwanide orogeny , as a foreland basin . In the Permian and Triassic the area between Asunción and Río Grande was uplifted in connection to the Gondwanide orogeny effectively splitting the basin in the two. The piling up of material in Bolivia and the Argentine Northwest during the Andean orogeny caused

1029-522: The sábalo ) are commercially important, and they are exploited for heavy internal consumption or for export. The Parana River delta ranks as one of the world's greatest bird-watching destinations. Much of the length of the Paraná is navigable , and the river serves as an important waterway linking inland cities in Argentina and Paraguay with the ocean, providing deepwater ports in some of these cities. The construction of enormous hydroelectric dams along

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1078-735: The African continent. The Late Jurassic to Early Cretaceous Gondwana III Supersequence is marked by two major events: A Cretaceous supersequence occurring in the north-central part of the basin and composed mainly of sandy-conglomeratic deposits. The northeasternmost part of the basin contains the Goio-Erê Formation , dating to the Turonian . In the Argentinian part of the basin, the Serra Geral Formation

1127-548: The Late Ordovician to Early Silurian , is constituted by three formations : Alto Garças Formation composed mainly of sandstones , Rio Ivaí Formation , represented by glacial Ordovician deposits that affected large areas of Gondwana and the Vila Maria Formation , a thick muddy sequence rich in fossil content: graptolites , trilobites , brachiopods and chitinozoa. This Devonian supersequence

1176-542: The Paraná River was the Venetian explorer Sebastian Cabot , in 1526, while working for Spain. A drought hit the river in 2021, causing a 77-year low. In eastern South America there is "an immense number of river names containing the element para- or parana- ", from Guarani language words meaning "river" or "sea"; attempts to derive a more precise meaning for the name of this, the largest of them, e.g. "kin of

1225-476: The Rio Paraná forms a massive drainage basin that encompasses much of the southcentral part of South America, essentially including all of Paraguay, much of southern Brazil, northern Argentina, and the southeastern part of Bolivia . If the Uruguay River is counted as a tributary to the Paraná, this watershed extends to cover most of Uruguay as well. The volume of water flowing into the Atlantic Ocean through

1274-515: The Río de la Plata roughly equals the volume at the Mississippi River delta . This watershed contains a number of large cities, including São Paulo , Buenos Aires , Rosario , Asunción , Brasília , and La Plata . The Paraná and its tributaries provide a source of income and of daily sustenance for fishermen who live along its banks. Some of the species of fish (such as the surubí and

1323-481: The Sun's solar cycle . The course of the Paraná is crossed by the following bridges, beginning upstream: Sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks . Most sandstone is composed of quartz or feldspar , because they are

1372-491: The application of tetraethyl orthosilicate (Si(OC 2 H 5 ) 4 ) which will deposit amorphous silicon dioxide between the sand grains. The reaction is as follows. Pore space includes the open spaces within a rock or a soil. The pore space in a rock has a direct relationship to the porosity and permeability of the rock. The porosity and permeability are directly influenced by the way the sand grains are packed together. Sandstones are typically classified by point-counting

1421-474: The city of Diamante, Entre Ríos , it splits into several arms and it forms the Paraná Delta . The main tributaries from the mouth: tributary tributary (km) (km ) (m /s) Tiestos Grandes de las Conchas Garupá Guazú Piray Guazú Piray Mini Guazú Urugua-i Francisco Falço Braço Sul Francisco Verdadeiro Guaçu (Arantes) Period: 1971–2000 Together with its tributaries,

1470-525: The common minerals most resistant to weathering processes at the Earth's surface, as seen in the Goldich dissolution series . Framework grains can be classified into several different categories based on their mineral composition: Matrix is very fine material, which is present within interstitial pore space between the framework grains. The nature of the matrix within the interstitial pore space results in

1519-552: The confluence with the Paraguay River, the Paraná again turns to the south for another approximately 820 km (510 mi) through Argentina, making a slow turn back to the east near the city of Rosario for the final stretch of less than 500 km (310 mi) before merging with the Uruguay River to form the Río de la Plata . This flows into the Atlantic Ocean . During the part of its course downstream from

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1568-456: The depositional environment, older sand is buried by younger sediments, and it undergoes diagenesis . This mostly consists of compaction and lithification of the sand. Early stages of diagenesis, described as eogenesis , take place at shallow depths (a few tens of meters) and are characterized by bioturbation and mineralogical changes in the sands, with only slight compaction. The red hematite that gives red bed sandstones their color

1617-407: The depth of burial, renewed exposure to meteoric water produces additional changes to the sandstone, such as dissolution of some of the cement to produce secondary porosity . Framework grains are sand-sized (0.0625-to-2-millimeter (0.00246 to 0.07874 in) diameter) detrital fragments that make up the bulk of a sandstone. Most framework grains are composed of quartz or feldspar , which are

1666-446: The different types of framework grains that can be present in a sandstone into three major categories: quartz, feldspar, and lithic grains. When sandstone is subjected to the great heat and pressure associated with regional metamorphism , the individual quartz grains recrystallize, along with the former cementing material, to form the metamorphic rock called quartzite . Most or all of the original texture and sedimentary structures of

1715-433: The greatest strain, and the strained mineral is more soluble than the rest of the grain. As a result, the contact points are dissolved away, allowing the grains to come into closer contact. Lithification follows closely on compaction, as increased temperatures at depth hasten deposition of cement that binds the grains together. Pressure solution contributes to cementing, as the mineral dissolved from strained contact points

1764-442: The hardness of individual grains, uniformity of grain size and friability of their structure, some types of sandstone are excellent materials from which to make grindstones , for sharpening blades and other implements. Non-friable sandstone can be used to make grindstones for grinding grain, e.g., gritstone . A type of pure quartz sandstone, orthoquartzite, with more of 90–95 percent of quartz, has been proposed for nomination to

1813-442: The most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand , sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topographic features, certain colors of sandstone have become strongly identified with certain regions, such as

1862-493: The much lower temperatures and pressures associated with diagenesis of sedimentary rock, but diagenesis has cemented the rock so thoroughly that microscopic examination is necessary to distinguish it from metamorphic quartzite. The term orthoquartzite is used to distinguish such sedimentary rock from metaquartzite produced by metamorphism. By extension, the term orthoquartzite has occasionally been more generally applied to any quartz-cemented quartz arenite . Orthoquartzite (in

1911-464: The narrow sense) is often 99% SiO 2 with only very minor amounts of iron oxide and trace resistant minerals such as zircon , rutile and magnetite . Although few fossils are normally present, the original texture and sedimentary structures are preserved. The typical distinction between a true orthoquartzite and an ordinary quartz sandstone is that an orthoquartzite is so highly cemented that it will fracture across grains, not around them. This

1960-638: The product of physical and chemical weathering of bedrock. Weathering and erosion are most rapid in areas of high relief, such as volcanic arcs , areas of continental rifting , and orogenic belts . Eroded sand is transported by rivers or by the wind from its source areas to depositional environments where tectonics has created accommodation space for sediments to accumulate. Forearc basins tend to accumulate sand rich in lithic grains and plagioclase . Intracontinental basins and grabens along continental margins are also common environments for deposition of sand. As sediments continue to accumulate in

2009-712: The red rock deserts of Arches National Park and other areas of the American Southwest . Rock formations composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs . Quartz-bearing sandstone can be changed into quartzite through metamorphism , usually related to tectonic compression within orogenic belts . Sandstones are clastic in origin (as opposed to either organic , like chalk and coal , or chemical , like gypsum and jasper ). The silicate sand grains from which they form are

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2058-706: The river is dammed by the Itaipu Dam, the third largest hydroelectric power plant in the world (following the Three Gorges Dam and the Baihetan Dam , both in the People's Republic of China ), creating a massive, shallow reservoir behind it. After merging with the Iguazu, the Paraná becomes the natural border between Paraguay and Argentina. Overlooking the Paraná River from Encarnación, Paraguay , across

2107-437: The river's length has blocked its use as a shipping corridor to cities further upstream, but the economic impact of those dams offsets this. The Yacyretá Dam and the Itaipu Dam on the Paraguay border have made the small, largely undeveloped nation of Paraguay the world's largest exporter of hydroelectric power . Due to its use for oceangoing ships, measurements of the water tables extend back to 1904. The data correlates with

2156-469: The river, is downtown Posadas, Argentina. The river continues its general southward course for about 468 km (291 mi) before making a gradual turn to the west for another 820 km (510 mi), and then encounters the Paraguay River , the largest tributary along the course of the river. Before this confluence, the river passes through a second major hydroelectric project, the Yacyretá Dam ,

2205-417: The sandstone are erased by the metamorphism. The grains are so tightly interlocked that when the rock is broken, it fractures through the grains to form an irregular or conchoidal fracture. Geologists had recognized by 1941 that some rocks show the macroscopic characteristics of quartzite, even though they have not undergone metamorphism at high pressure and temperature. These rocks have been subject only to

2254-526: The sea", have been discounted. The course is formed at the confluence of the Paranaiba and Rio Grande rivers in southern Brazil. From the confluence the river flows in a generally southwestern direction for about 619 km (385 mi) before encountering the city of Saltos del Guaira , Paraguay. This was once the location of the Guaíra Falls (Sete Quedas waterfalls, where the Paraná fell over

2303-626: The world in constructing temples, churches, homes and other buildings, and in civil engineering . Although its resistance to weathering varies, sandstone is easy to work. That makes it a common building and paving material, including in asphalt concrete . However, some types that have been used in the past, such as the Collyhurst sandstone used in North West England , have had poor long-term weather resistance, necessitating repair and replacement in older buildings. Because of

2352-616: Was deposited, represented by bituminous shale , a potential petroleum source rock, and famous worldwide for its Mesosaurus fauna . The top of this supersequence defines the end of the marine phase. This Triassic supersequence marks the beginning of continental sedimentation. The Santa Maria Group comprises the Candelária , Caturrita and Santa Maria Formations. In the Santa Maria Formation , it bears an important reptile and mammal fauna, that can be correlated to

2401-793: Was the discovery of Mesosaurus fossils within Permian black shales ( Irati Formation ), and the Glossopteris flora within the Permian coals. White was one of the first to propose the equivalence between the South American Permian strata and similar rocks of the Karoo Basin in South Africa . The basin developed during the Paleozoic and the Mesozoic with a sedimentary record comprising rocks from

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