O arquipélago dos Abrolhos: Geomorfologia e Aspectos Gerais

Abstract

Physiographic aspects of the Abrolhos archipel are des cribed with the purpose to contribute information for the manage ment plan of the newly created marine park. The archipel, composed by four major islands and one minor one, are of vulcanic character. Tow of the islands, Santa Barbara and Redonda, shows strata of sedimentary rocks, mainly sandstones, with Intercalations of basaltic intrusions. The others are entirely composed of mafic rocks. The region suffered a tilting of about 13º to NNW, resulting in asymmetric topographic profiles with the development of high cliffs at the south side of the islands. A wave abrasion platform is found with interruptions around the islands. Low precipitation and high evaporation results in a water deficit that inhibits the development of soils and vegatation making the islands unsuitable for heavy visitation.