Morfodinâmica de praias dominadas por mesomarés na Planície Arenosa de Almofala, NW do Ceará (Brasil)

Abstract

Morphodynamic of beaches dominated by Mesotide in the Almofala Sandy Plain, NW of Ceará (Brazil). The morphodynamics of the oceanic beaches of the Almofala sandy plain varies due to the oceanographic parameters (waves, tides and coastal currents), meteorological (rains, winds and storms) and anthropogenic (shrimp farms). The objectives are to analyze the processes of progradation and retrogradation of the coastline and the morphodynamics of beaches. The Almofala, Barreira and Torrões beaches are located on the west coast of Ceará. The methodology consisted of the acquisition of topographical data (DGPS), oceanographic parameters (period, direction, high wave and tidal range) and sediments samples. These beaches had RTR with dominate wave. The parameter ε showed longitudinal bar and runnel system on the Almofala and Torrões beaches, and reflective on the Barreira beach. The parameter Ω showed intermediate terrace stage on the beach at the low tide on the Almofala beach and dissipative stage on the Barreira and Torrões beaches, with a predominance of fine grain sand (44%) and on the Almofala and Torrões beaches and medium sand (29%) on the Barreira beach. These beaches are semi-exposed, operating winds (5,5 m/s) and waves (0,56 m), with erosion in the Barreira beach (-64,5 m³) and Torrões beach (-72,1 m³), and accretion (62,83 m³) in the Almofala beach, according year of 2007.