Caracterización de las acumulaciones loéssicas en el valle medio del río Tajo, España

Abstract

The Central Spain plains have a great paleoclimatic interest. They are located around 40° N and at heights of 450/650 m.a.s.l. During the Pleistocene their paleosedimentary environment developed under Mediterranean climates, degraded or separated by small hiatus. In these plains, loess represents one of the most suitable surface deposits to reconstruct past environments and for the determination of climate changes. For this study, over one hundred samples from such deposits were collected, in which the determination of physical properties was carried out through mechanical analysis. The age of the loess has been obtained by thermoluminescence and can be linked to the Oxygen isotope (OIS) 3 and 2 (Würm period and Late Glacial) phases. The loess are correlated with other cold features in this area. Among them, are the «stratified debris slope deposits» related to breakdown by seasonal freezing and thawing.