The coastal zone is influenced by oceanic, atmospheric and continental agents, that present a complex system of depositional environments. The northeastern Pará has 600km of wid, where are found several coastal environments such as beaches, mangroves and estuaries. This coast being cut by tidal channels that represents ebb tidal deltas, as in tip Mariteua, Guará Island, micro-region of Salgado Paraense. The objective of this resarch was understood the morfosedimentation in the tip Mariteua based in sedimentological data analisys obtained through treatment and processing of surface sample in 4 shore line transversal transect, were was collect topographic informations whit Total Station Equipment.in field visits in three months of the year 2010 (March, May and August). The sediment transport was determined from the grain size trend analysis and comparing this trends between near stations. The Marituea tip presented strong erosive trend, comproved by destruction of houses, vegetation and dunes near the high tide line, being more evident during the rainy months, and constant removal of sediment confined to channels. In Mariteua tip during March (rainy period) fine grand was totaly predominant (100%), very well selected (75%), assymetry approximately symmetrical (54%) and leptokurtic kurtosis (55%). In May (transition period) were fine grain was predominantly (99%), very well selectedd (70%), assymmetry approximately symmetrical (60%) leptokurtic kurtosis (78%). In August (less rainy period) there was fine sand predominiun (98%), very well selected (70%), negative asymmetry (59%) and kurtosis mesocúrtica (80%). The changes in the distribution of granulometric statistical parameters in the different months of the study are related to the dynamics of the channels that cut the delta and tidal channel near. The morphology of these varies with the different energy levels in different seasons, where sediments of larger diameter were found farther from the AML followed by months of study
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