Pulsos de inundación marina en la terminación de una plataforma carbonatada (Aptiense inferior de Aralar, Cuenca Vasco-Cantábrica)

Abstract

The Lower Aptian Sarastarri Limestone unit (Aralar, nor thern Spain), mainly consists of rudist and coral micrites and is nearly 200m thick. The uppermost 30m of the unit show sharp-based marly intervals attributed to two drowning events. Both marly intervals are immediately preceeded by laminated bioclastic rudstone facies, attributed to quick shoaling processes ending with subaerial exposure. A change of local subsidence conditions from uniform during the Sarastarri Limestone episode, to varying with distance during the Lareo Marl succeeding episode, is invoked to explain both drownings. Influence of oceanographic causes reported in other contemporaneous carbonate platforms is, however, not excluded