Geology and relief. About 52% of Paraná’s territory is over 600m and 89% over 300m; only three percent are below 200m. The morphological picture is dominated by flat surfaces arranged at high altitude, composing steep plateaus forming the mountains of Mar and Geral. Five units of relief follow each other from east to west, in the following order: coastal lowlands, Serra do Mar, crystalline plateau, paleozoic plateau and basaltic plateau.
The coastal lowland forms a strip of lowland with about twenty kilometers of average width. It comprises low and floodable terrains (alluvial plains and sandy formations) and crystalline hills approximately fifty meters high. In its northern portion, the coastal lowlands fragment to give way to the bay of Paranaguá, whose digitized aspect results from the penetration of the sea through old river valleys, that is, from the formation of rivers.
The Serra do Mar is the eastern edge of the crystalline plateau and dominates the coastal plain with its energetic escarpments. In the state of Paraná, unlike what occurs in São Paulo, the mountain range is fragmented into isolated massifs, including the level of the crystalline plateau (900m) until reaching the eastern edge. In general, the massifs exceed this level by one hundred meters. This means that in Paraná the Serra do Mar, in addition to the escarpment that faces east with a difference of one thousand meters, also presents an interior escarpment, facing west. However, this shows a gap of only one hundred meters.
The crystalline plateau, also called the first plateau of Paraná, presents a strip of crystalline terrain, which extends north-south, west of the Serra do Mar, with an average width of one hundred meters and about 900 meters high. The topography varies from rugged in the north to gently rolling in the south. An old lake, now full of sediments, forms the sedimentary basin of Curitiba.
The paleozoic plateau, also called the second plateau of Paraná or the plateau of Campos Gerais (or Ponta Grossa), develops in lands of the paleozoic period. It is bordered, on the east, by a escarpment, the Serrinha, which falls to the crystalline plateau and, on the west, by the wall of the Serra Geral, which rises to the basaltic plateau. The paleozoic plateau has a smooth topography and a slight slope to the west: at its eastern end it reaches 1,200m in height and, at the base of the Serra Geral, to the west, it registers only 500m. It forms a strip of land approximately one hundred kilometers wide and describes a gigantic half-moon, the concave of which faces east.
The basaltic plateau, or third plateau of Paraná, also called the Guarapuava plateau, is the most extensive of the state’s relief units. The Geral mountain range limits it to the east, which, with a 750m difference in altitude, dominates the Paleozoic plateau. To the west, the limit is marked by the Paraná River, which downstream of the point where the falls of Sete Quedas were, forms an impressive gorge (in fact, the plateau extends beyond the limits of the state of Paraná and forms part of the territories of Mato Grosso do Sul, Paraguay and Argentina).
Like the paleozoic plateau, the basaltic plateau gently descends to the west: it falls from 1,250m, to the east, to 300m on the banks of Paraná (upstream from Sete Quedas). Formed by a succession of basalt spills, stacked on top of each other, this plateau occupies the entire western half of the state. Its soils, developed from the products of the decomposition of basalt, constitute the “purple earth”, famous for its fertility.
Vegetation
According to plus-size-tips.com, two types of vegetation occur in Paraná: forests and fields. Forests are subdivided into tropical and subtropical. The fields, in clean and closed. The tropical forest is part of the Atlantic forest, which covered the entire eastern façade of the country with its broadleaved formations. In Paraná, it originally occupied an area equivalent to 46% of the state, including the lower portions (coastal lowlands, slopes of the Serra do Mar, Paraná, Iguaçu, Piquiri and Ivaí valleys) or of lower latitude (the entire northern part of the state). state).
The subtropical forest is a mixed forest, composed of broadleaf and coniferous formations. The latter are represented by the paraná pine (Araucaria angustifolia), which does not appear in pure clusters. The mixed forest or pine forest covered the highest portions of the state, that is, most of the crystalline plateau, the easternmost portion of the basaltic plateau and a small part of the paleozoic plateau. This formation occupied 44% of Paraná’s territory and still part of the states of São Paulo, Santa Catarina and Rio Grande do Sul. Currently, the country’s forests suffer the greatest economic exploitation, as it is the only one with a large number of individuals same species (pines) in clusters sufficiently dense (although not pure) to allow easy extraction.
In addition to the pine tree, the mixed forest also offers broadleaved species of economic value, such as imbuia, cedar and yerba mate. At the end of the 20th century, only a small part of forest formations remained in the state. Felling for logging and formation of fields for agriculture or pasture was responsible for its almost complete elimination. The last forest reserves in Paraná are found on the coastal plain, on the slopes of the Serra do Mar and in the valleys of the Iguaçu, Piquiri and Ivaí rivers.
Clean fields occur in the form of sparse patches across the plateaus of Paraná. The most extensive of these patches is that of the so-called general fields, which cover the entire eastern portion of the Paleozoic plateau and describe an immense half-moon on the state’s vegetation map. Other patches of clean field are those of Curitiba and Castro, on the crystalline plateau, those of Guarapuava, Palmas and others, smaller ones, on the basaltic plateau. Clean fields occupy about nine percent of the territory of Paraná. The closed fields have little expression in Paraná, where they occupy a very small area – less than one percent of the state’s surface. They form small patches in the paleozoic plateau and in the basaltic plateau.
