Brazil Geology 4

Brazil Geology and Morphology Part 4

According to sourcemakeup.com, the coast is generally low and lagoon throughout the vast area where the Amazon River estuary and the Tocantins-Pará estuary join, divided by the island of Marajó as wide as Switzerland, facing N. by the islands of Caviana and Mexiana and in which the rocky base emerges, as well as in the section to the north of the estuary itself, up to the Cape of Orange, and to the SE. up to the mouth of the Gurupí. Then it, less bare, engraved by small breasts, surrounded by small islands, becomes higher, up to the gulf of S. Marcos, which the island of S. Luiz de Maranhão divides from that of S. Josè.

It then continues for more than 150 km. monotonous and sterile, up to the Parnahyba delta, and even without salient features is the remaining coastal stretch of the states of Ceará and Rio Grande do Norte up to Cape Calcanhar, to the NW. di Capo S. Rocco, where ESE general management ends. From Capo Calcanhar to Porto de Pedras, in the states of Rio Grande do Norte, Parahyba, Pernambuco and Alagôas, the general course of the coast, while slightly bending towards the east, does not depart from the direction of the meridian, as well as later, up to the southern extremity: of the Confederation, it does not depart from the general direction of SSO. After the mouth of the S. Francisco the terrain appears more rugged, more frequent are the inlets, including a real large gulf: the Bahia de Todos os Santos, semi-elliptical, which, partly barred towards midday by the island of Itaparica, it goes in for about 80 km. among the lands (v. Bahia). The Itacolomí (Itacolomis) coral group, which reaches the latitude of M. square kilometers, emerges in front of Caravellas. Then the coast becomes low and marshy between the mouth of the Rio Doce and the Bahia de Victoria or de Espirito Santo, to return bumpy and irregular up to the mouth of the Parahyba (north of the Cape of S. Thomé) and then again low and lagoon (Bananeiras, Salgada, Feia, Carapebús lagoons), up to Capo Frio. And another festoon of lagoons (Araruama, Saquarema, Maricá) stretches along the thin and sterile border between C. Frio and the Bay of Rio de Janeiro. This is Guanabara, 400 sq km wide, full of coves, like those of Juruiuba and Armaçào in the eastern section, of Botafogo and Sacco do Caiú in the western one: a real “hidden lake, set with islands”, including those of Governador and Paquetá, das Cohras, Villegaignon and Lage “with the its strange fortress similar to a gigantic whale watching over the entrance “. After a short stretch of low lands, other arms of the sea that simulate the appearance of lakes between promontories, and picturesque rocks and islands, such as the mountainous Ilha Grande; then a group of smaller islands around the greater and higher island of São Sebastião (1300 m) facing the extreme southern offshoots of the Serra do Mar. Further south, the coast appears typically low where, between low and sandy islands, the Mar Pequeno de Iguapé in the State of S. Paolo as he returns high and jagged in the state of Paraná, where is the vast inlet named after Paranaguá, connected by rail to the capital Curityba. Along most of the coast of Santa Catharina, faced by the islands of San Francisco and Santa Catharina, the general trend is in the direction of the meridian, almost as far as the Punta di Santa Martha Grande from which the general direction of SW resumes. In the state of Rio Grande do Sul the coast is arid, monotonous, bordered by lagoons, including the long and low Lagoa dos Patos, which a narrow sandy rim divides from the sea and a channel (Rio de S. Gonçalo) connects with the Lagôa Mirim.

Overall, while there is no shortage of vast river islands (of Sant’Anna, between two branches of the Araguaya, a western tributary of the Tocantins, of Tupinambarana in the Amazon River, not far from the mouth of the Madeira, etc.), and not to mention those of the estuarî of the Amazons and Pará, the area of ​​the coastal islands appears very limited, and even smaller is that of the so-called oceanic islands. Among these is the group that perhaps from the first discoverers had the name of S. Giovanni, to then soon assume that of Fernando de Noronha, at about 3 ° 50 ′ lat. S. The main island of the group, about 15 sq km wide. and a half, it rises 500 nautical miles NE. from the Pernambuco coast: volcanic, bordered by vermilion sand dunes, rich in phosphates, with agricultural production closely related to precipitation, it had only strategic value and function as a deportation area, until the very recent advances in the air force gave it a new task. NE. by Fernando de Noronha, and properly at about 0 ° 55 ′ lat. N. and 29 ° 15 ‘. long. O., there is a group of conical rocks, barely 20 meters high (Penedo do S. Pedro and do S. Paulo), while almost at the same longitude, but at about 21 ° S., is the group that has its name from greater island of Trinidade (640 miles from the coast of the state of Espirito Santo), and not far away the group of Martin Vaz, made up of three islets.

Brazil Geology 4