Marco estratigráfico y sedimentológico de los yacimientos paleontológicos miocenos de Somosaguas (Madrid, España)

Abstract

Two new fossiliferous sites (Somosaguas Norte and Somosaguas Sur), dated as middle Aragonian (biozone E), are situated in the Miocene Intermediate Unit of the Madrid basin, in the Campus de Somosaguas of the Universidad Complutense de Madrid (Pozuelo de Alarcón, Madrid, Spain). The stratigraphic sequence more than 6 meters thick is made up by three litostratigraphic units: a lower unit (T1) formed by arkosic sands with clay matrix; an intermediate unit (T2) made by intercalations of fine-grained micaceous sandstones with climbing ripples, and brown lutites; and an upper unit (T3) formed by arkosic conglomerates with sandy matrix. These sediments represent the middle (T1 and T3) and distal (T2) facies of alluvial fans.