Geomorfologia costeira e morfologia praial da planície costeira do município de Marapanim (PA).

Abstract

The geomorphology of the Paraense coast is basically formed by three geomorphological units: Residual Massif, Plateaus Zone and Lowered Plateau of the Amazon. The beaches of the municipality of Marapanim, located in the northeastern Paraense, in the physiographic sector Atlantic Coast of Salgado Paraense, are influenced by a semidiurnal macromaric dynamics of amplitudes around 5m. In order to better understand geomorphological and coastal dynamics, a cartographic and bibliographical survey was carried out, aerial photographic survey with drone, topographic survey of seven morphological profiles, two on Araticum-Mirim beach, three on Crispim beach , one on the beach of Marudá and one on the beach of Lembe, later through the digital processing of these profiles it was possible to characterize two large geomorphological compartments: Coastal Plateau (cliffs and abrasion platforms) and Coastal Plain (tidal plain lamosa mangroves, estuaries, dunes and beaches). Through a topographic survey, one can see beaches with an extensive intermaré zone, in which its dynamics form a high energy environment, presenting a typical pattern of dissipative and intermediary beaches. With lower slope of the intermaré zone in profile 2 of Crispim beach, with topographic difference existing between the limits of this zone of 2.6m and, in contrast, the beach of Lembe with the topographic difference between the limits of the zone of intermaré of 5,6m. The other beaches did not show a great topographic variation between their profiles, presenting topographic difference between the intermaré limits of 2.9m and 3.2m, in addition to the slope of the upper intermarine zone of 1º10'18 "and 2º17'26", in the zone of intermaré average 0º20'04" and 0º50 ', in the zone of inferior intermaré 0º07'05" and 0º25'44 "for the beaches of Marudá and Araticum-Mirim, respectively.