Regresar

Análisis petrográfico y estratigráfico de las terrazas marinas de la Formación Tablazo provincia de Santa Elena-Ecuador

Abstract:

The Tablazo Formation is in discordance with Cretoceous-Paleogene rocks from the Peninsula de Santa Elena. The age assigned is Pleistocene and a shallow marine depositional environment. This study is focused in the stratigraphic, sedimentary and petrographic description of the Tablazo Formation to detail the sedimentary environment. Three outcrops were chosen to macroscopic petrographic, texture and cementation type description from hand samples. The Dunham classification (1962) and the Bernard method (1967) for carbonate rocks were used, also calcimetry analysis. The rocks have an average of 52% of calcium carbonate composition and correspond to grainstones formed by fragments of organisms (bivalvos and foraminifera shells), and in a smaller proportion, other components were identified such as plagioclase and micas joined with carbonate cement, as observed in the thin sections, this cement corresponds to microesparite. Finally, the sites studied correspond to high-energy environemts.