After that (it has less than 70 million years) the African continent if moved away from American, shortening s distance, the east, ties the Atlantic Ocean. But only well later, it has 12 million years (Tertiary period) the rise of the mountain range of Andes, formed an important barrier in the place where internal depressions and seas existed, blocking the exit of the river for Pacifico, flowing then in direction it opposes for the Atlantic, as it makes until today. Source: All the cited episodes, had occurred of slow form throughout millions of years. After ' ' fechamento' ' for the mountain range of Andes and before the river ' ' transbordasse' ' for the Atlantic, it had the formation of enormous lakes that occupied the area of the current hidrogrfica basin. During this long period of backwaters, immense amounts of sediments in suspension (or carried for rains when draining for the surfaces of the ground) had been precipitated and accumulated in deep of the lakes, constituting sedimentary lands. With the opening for the side of Atlantic, forming the current estuary, the dammed waters if had flowed off, the lands had dried and this ground sedimentary started to be town for the vegetation (current Amazonian forest).
Amazonian complex (River and Tributaries) Source: Source: Images of Google.com.br This complex system of rivers, in general very crooked because of the planura of the land. The river Amazon, constitutes the main axle or spine of this fluvial system, is divided in three main pursuings: the first one, whose springs if find in Andes Peruvian are the river Maraon. As the segment is when entering in the Brazilian territory (after the borders of Peru and Colombia) that it takes the name of the river Solimes. finally, when receiving the great Black river (in front of city of Manaus) is then that the river Amazon is initiated, the third segment, ties to discharge in the Atlantic.