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Welcomes you to the Icebreaker Party

Survey and Dredge in High protected Environmental Vulcanic open sea Island

Fontes, José Bartolomeu, Siqueira, Hailton

 

Fernando de Noronha is an isolated volcanic archipelago in the Atlantic South Equatorial, and its main island the visible part of a chain of underwater mountains (DORSAL MEDIAN ATLANTIC), located in the geographic coordinates 03 51’south and 32 25′ west, and distant about 345 miles from Cape St. Roque in the state of Rio Grande do Norte and 545 miles from Recife, Pernambuco. Consisting of 21 islands, islets and rocks of volcanic origin, the main island Rasa area of 18.4 km2 whose major axis about 10 km, maximum width of 3.5 km and a perimeter of 60 km. The base of this enormous volcanic formation is more than 4,000 meters deep. The main island, whose name is the same archipelago, is 91% of the total area, highlighting also the islands of Rata, Sela Gineta, Hairy, St. Joseph and the islets of the Lion and the Widow. Studies show that the formation of islands time of two to twelve million years.
Faced with severe environmental constraints the objective of the work of dredging was to ensure a safe depth for the boats that supply the island with the basic materials for life of the islanders. In addition to fuel, food, water and products, the removal of all trash in the archipelago is made by the port. Furthermore the movement of boats of tourism, based on the local economy, carry out the transfer of tourists also in the port of Fernando de Noronha.
A portion of the dredged material was disposed at a depth of 50 meters and the other was used for the distribution on the island, since the high quality sand for construction has one of the world’s highest costs in the archipelago.
We used two types of dredges and for a better result. The bathymetry was essential for the evaluation and monitoring of underwater features and behavior of the material. Some objects in the background as the show features special wreck barge near the access channel.