Asociaciones de foraminíferos bentónicos y evolución paleoambiental del Plioceno inferior en el sector de Elche-Crevillente (Cuenca del Bajo Segura, Alicante) : resultados preliminares

Abstract

Benthic foraminifer assemblages of two Early Pliocene sections located between Elche and Crevillente are studied. In both sucessions three stratigraphic units are distinguished: P0 Unit, littoral conglomerates (transgressive lag); P1 Unit, pelagic marl-dominated interval; and P2 Unit, shallow marine calcarenites. Benthic foraminifers in the P1 and P2 Units are grouped in three main paleoecological categories: shallow water euryhaline (A), intermediate water (B), and deep water stenohaline (C). Distribution trends in these paleoecological groups, planctonic/benthonic ratios, and sedimentological data permit the reconstruction of the Early Pliocene paleoenvironmental evolution of this area. End-Messinian unconformity corresponds to an incissed valley, subsequently filled with Early Pliocene marls (P1). The acommodation space reduction determined the progressive decrease of the planctonic and the deep water stenohaline benthic foraminifers.