RECONHECIMENTO E MAPEAMENTO SÍSMICO DE PALEOCANAIS AO LARGO DA PLATAFORMA CONTINENTAL INTERNA DA ILHA DE SANTA CATARINA.

The characteristics of bottom and shallow subsurface of the adjacent internal continental shelf of Santa Catarina island were mapped through the interpretation of 27 seismic profiles. Those seismic profiles demonstrated eight sedimentary structures correlated to ancient fluvial systems, thus considered as paleochannels. The identified acoustic reflectors, which represent contacts between sedimentary strata, named R1, R2 and R3, bounded old depositional scenarios and represent, past drainage systems. The identified paleochannels were strongly associated with sea level fluctuations from the transgressive phase, which began after the Last Glacial Maximum with the river mouths and coastal plain drowning, until the subsequent cover of those structures by transgressive sands conforming the current adjacent continental shelf of the island of Santa Catarina. [ABSTRACT FROM AUTHOR]