The Mearim River is a river in
Maranhão
Maranhão () is a state in Brazil. Located in the country's Northeast Region, it has a population of about 7 million and an area of . Clockwise from north, it borders on the Atlantic Ocean for 2,243 km and the states of Piauí, Tocantins and ...
state of northern
Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
. The river originates in the southern part of Maranhão, and drains north into the
Baía de São Marcos, an
estuary
An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environm ...
that also receives the
Pindaré and
Grajaú rivers, which are sometimes considered tributaries of the Mearim. The lower Mearim is known for its
pororoca
The Pororoca (, ) is a tidal bore, with waves up to high that travel as much as inland upstream on the Amazon River and adjacent rivers. Its name might come from the indigenous Tupi language, where it could translate into "great roar". It could b ...
, or
tidal bore
Tidal is the adjectival form of tide.
Tidal may also refer to:
* ''Tidal'' (album), a 1996 album by Fiona Apple
* Tidal (king), a king involved in the Battle of the Vale of Siddim
* TidalCycles, a live coding environment for music
* Tidal (serv ...
.
The Mearim is approximately 800 kilometers long, flowing through the marshlands of the Atlantic Coastal Plain. It meets the Atlantic Ocean at the
Sao Marcos Bay, where it forms a common estuary with another river,
Pindare. The Mearim's primary source of water is rain. The river's upper and middle courses are characterized by rapids. Only the lower sections of the Mearim are suitable for navigation.
The river defines the southern boundary of the
Tocantins–Araguaia–Maranhão moist forests
The Tocantins–Araguaia–Maranhão moist forests (NT0170), also called the Tocantins/Pindaré moist forests, is an ecoregion in the north of Brazil to the south of the mouth of the Amazon River. It is part of the Amazon biome.
The ecoregion con ...
ecoregion.
References
Rivers of Maranhão
Tidal bores
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