c of relati vo sea-lcvel fluct uatio ns durin g t he Upper Quat ern ary are repr esen ted by nurncrou s geological, bio logica l, and pre-historical (shell-midd ens) re cord s foun d along th e Brazilian coast líne. Aba ut 700 of th esc rccord s, dated most1y by the radiocarbon method , are d istrib ut cd t hrough th e Stat es of Alagoas, Sergipe. Bah ia, Esp írito Santo, Rio de Janeir o, São Paul o, Paraná, and Santa Cata rina. T he coasta l plains of th ese states , representing about 50% of th e Brazilian coast, havc beco geo logically mapped , in part or entlre ly during t he last lO years. Th e geological map s are accompan ied by sea levei fluctuati on curves for the past 7,000 years for the Stat es of Bahia (Salvador, Ilhéus, and Caravelas sectors), Rio de Janeiro (Angra dos Reis sector), São Paulo (Santo s and Cananéia-Iguape sectors), Paraná (Paranaguá sector) and Santa Catarina (Itajaf-Laguna sector). These informations allowed us t o kno w that th e relat ive sca levei fluct uations during t he last t housand years played a very importan t role in th c constru ction of the Brazilian Coastal plains. It was alsc demon strated th at th e relative sea levei fluctu at ions during thc Upper Quaternary have been important for th e constru ction of t he river mouth coasta l plains of São Francisco (SE/AL), Jequitinhonha (BA), Doce (ES) and Paraíb a do Sul (RJ) rivers, whose evolutionary histories were quite different in relation to th e classical delta plains prcsent ed in th e geological literature.

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This paper presents a numerical modeling estimation of the sediment dispersion patterns caused by waves inciding through four distinct coastline contours of the delta plain of the Doce River during the Late Holocene. For this, a wave climate model based on the construction of wave refraction diagrams, as a function of current boundary conditions, was defi ned and was assumed to be valid for the four coastlines. The numerical modeling was carried out on basis of the refraction diagrams, taking into account the angle of approximation and the wave height along the coastline. The results are shown to be comparable with existing data regarding the directions of net longshore drift of sediments estimated from the integration of sediment cores, interpretation of aerial photographs and C 14 datings. This fact apparently suggests that, on average, current boundary conditions appear to have remained with the same general characteristics since 5600 cal yr BP to the present. The used approach may prove useful to evaluate the sediment dispersion patterns during the Late Holocene in the Brazilian east-northeast coastal region.

PATTERNS OF SEDIMENT DISPERSION ALONG THE DISCOVERY COAST (BRAZIL) The patterns of sediment dispersion along the Discovery Coast (Brazil) is characterized by three sediment longshore transport divergent zones. The divergent zones were defined through analysis of the wave climate along with wave refraction diagrams and the establishment of a sediment dispersion model. In the study area the sediment dispersion and the associated divergent zones are mainly controlled by coral reefs located along the coast, forming a barrier to the stronger SE and SSE waves. This causes, in some coastal segments, an inversion in the sediment drift direction, due to the dominance of the weaker E and NE waves.

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