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Brazil Size and Location
Size and Location
With its expansive territory, Brazil occupies most of the eastern
part of the South American continent and its geographic heartland,
as well as various islands in the Atlantic Ocean. The only countries
in the world that are larger are Russia, Canada, China, and the
United States (including Alaska). The national territory extends
4,395 kilometers from north to south (5°16'20" N to 33°44'32"
S latitude) and 4,319 kilometers from east to west (34°47'30"
E to 73°59'32" W longitude). It spans four time zones,
the westernmost of which, in Acre State, is the same as Eastern
Standard Time in the United States. The time zone of the capital
(Brasília) and of the most populated part of Brazil along
the east coast is two hours ahead of Eastern Standard Time, except
when it is on its own daylight savings time, from October to February.
The Atlantic islands are in the easternmost time zone.
Brazil possesses the archipelago of Fernando de Noronha, located
350 kilometers northeast of its "horn," and several small
islands and atolls in the Atlantic--Abrolhos, Atol das Rocas, Penedos
de São Pedro e São Paulo, Trindade, and Martim Vaz.
In the early 1970s, Brazil claimed a territorial sea extending 362
kilometers from the country's shores, including those of the islands.
On Brazil's east coast, the Atlantic coastline extends 7,367 kilometers.
In the west, in clockwise order from the south, Brazil has 15,719
kilometers of borders with Uruguay, Argentina, Paraguay, Bolivia,
Peru, Colombia, Venezuela, Guyana, Suriname, and French Guiana (see
table 2, Appendix). The only South American countries with which
Brazil does not share borders are Chile and Ecuador. A few short
sections are in question, but there are no major boundary controversies
with any of the neighboring countries.
Geology, Geomorphology, and Drainage
In contrast to the Andes, which rose to elevations of nearly 7,000
meters in a relatively recent epoch and inverted the Amazon's direction
of flow from westward to eastward, Brazil's geological formation
is very old. Precambrian crystalline shields cover 36 percent of
the territory, especially its central area. The principal mountain
ranges average elevations just under 2,000 meters. The Serra do
Mar Range hugs the Atlantic coast, and the Serra do Espinhaço
Range, the largest in area, extends through the south-central part
of the country (see fig. 3). The highest mountains are in the Tumucumaque,
Pacaraima, and Imeri ranges, among others, which traverse the northern
border with the Guianas and Venezuela.
In addition to mountain ranges (about 0.5 percent of the country
is above 1,200 meters), Brazil's Central Highlands include a vast
central plateau (Planalto Central). The plateau's uneven terrain
has an average elevation of 1,000 meters. The rest of the territory
is made up primarily of sedimentary basins, the largest of which
is drained by the Amazon and its tributaries. Of the total territory,
41 percent averages less than 200 meters in elevation. The coastal
zone is noted for thousands of kilometers of tropical beaches interspersed
with mangroves, lagoons, and dunes, as well as numerous coral reefs.
Brazil has one of the world's most extensive river systems, with
eight major drainage basins, all of which drain into the Atlantic
Ocean. Two of these basins--the Amazon and Tocantins-Araguaia--account
for more than half the total drainage area. The largest river system
in Brazil is the Amazon, which originates in the Andes and receives
tributaries from a basin that covers 45.7 percent of the country,
principally the north and west. The main Amazon river system is
the Amazonas-Solimões-Ucayali axis (the 6,762 kilometer-long
Ucayali is a Peruvian tributary), flowing from west to east. Through
the Amazon Basin flows one-fifth of the world's fresh water. A total
of 3,615 kilometers of the Amazon are in Brazilian territory. Over
this distance, the waters decline only about 100 meters. The major
tributaries on the southern side are, from west to east, the Javari,
Juruá, Purus (all three of which flow into the western section
of the Amazon called the Solimões), Madeira, Tapajós,
Xingu, and Tocantins. On the northern side, the largest tributaries
are the Branco, Japurá, Jari, and Negro. The above-mentioned
tributaries carry more water than the Mississippi (its discharge
is less than one-tenth that of the Amazon). The Amazon and some
of its tributaries, called "white" rivers, bear rich sediments
and hydrobiological elements. The black-white and clear rivers--such
as the Negro, Tapajós, and Xingu--have clear (greenish) or
dark water with few nutrients and little sediment.
The major river system in the Northeast is the São Francisco,
which flows 1,609 kilometers northeast from the south-central region.
Its basin covers 7.6 percent of the national territory. Only 277
kilometers of the lower river are navigable for oceangoing ships.
The Paraná system covers 14.5 percent of the country. The
Paraná flows south into the Río de la Plata Basin,
reaching the Atlantic between Argentina and Uruguay. The headwaters
of the Paraguai, the Paraná's major eastern tributary, constitute
the Pantanal, the largest contiguous wetlands in the world, covering
as much as 230,000 square kilometers.
Below their descent from the highlands, many of the tributaries
of the Amazon are navigable. Upstream, they generally have rapids
or waterfalls, and boats and barges also must face sandbars, trees,
and other obstacles. Nevertheless, the Amazon is navigable by oceangoing
vessels as far as 3,885 kilometers upstream, reaching Iquitos in
Peru. The Amazon river system was the principal means of access
until new roads became more important in the 1970s. The São
Francisco was also used for transportation in the past. Dams and
locks in the Paraná system have made it an important artery
for interstate and international trade in the 1990s.
The various river systems descending from the shields have endowed
Brazil with vast hydroelectric potential, estimated at 129,046 megawatts
(MW), of which 30,065 MW were in operation or under construction
in 1991. The largest hydroelectric projects are Itaipu, in Paraná,
with 12,600 MW; Tucuruí, in Pará, with 7,746 MW; and
Paulo Afonso, in Bahia, with 3,986 MW.
Data as of April 1997
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