GEOMETRIA DA UNIDADE ALOSTRATIGRÁFICA SLD13 (ZANCLEANO SUP. - GELASIANO) NO SECTOR SW DA BACIA CENOZÓICA DO BAIXO TEJO (ALPIARÇA - PENÍNSULA DE SETÚBAL) – INTERPRETAÇÕES DEPOSICIONAIS E TECTÓNICAS

Abstract

The geometry of the allostratigraphic unit SLD13 (uppermost Zanclean to Gelasian) in the area of Alpiarça - Setúbal Península (Lower Tejo Cenozoic Basin) was investigated. The methods involved comprised: a) literature review; b) identification of the unit base and top surfaces from geological maps 1/50000; c) production of maps with the altitudes of the base and top surfaces; d) production of maps with structure contours of the base surface; e) interpretation of the geometry of basal and top surfaces. The geometry of the basal surface allows us to identify large paleovalleys and the main paleodrainage axis, but also the sin-sedimentary tectonic deformation and the more recent tectonic displacements.