Mapeamento de Ecocaráteres no Sistema Estuarino do Piraquê-Açu, Aracruz – Es

This research is an attempt that through the recognition of echo characters to start a study on geology/sedimentology of the Piraque-açu river estuary, estuary system located in Aracruz, ES. The echo characters recognition and mapping were accomplished through high resolution seismic and superficial sedimentology. With the association of these data, geophysical and sedimentalogical were recognized three echo characters pattern, which were subdivided according to the seismic signature characteristics (reflection and penetration) totalizing seven estuary echo characters. The spatial distribution of these allows a division of the estuary system in three distinct areas that differ by the prevalence of a kind of echo character and the type of sediment. These characteristics can be associated to distinct sedimentary processes in this estuary: i) the mouth of the estuary, where prevails the sand and the low penetration; ii) the zone of join, where sand-mud and mud-sand sediments and pattern of reflection determined by the bottom sediment and geology; iii) The rivers Piraque-açu and Piraque-Mirim with predominance of sand-mud and mud-sand sediments and echo character with penetration influenced by the mud concentration and geology/ sub superficial reflectors. In this sectors, the morphology/geology estuarine tertiary sediments and outcrops limiting the penetration of seismic.