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The most important stratified screes of the Iberian Range are found in Sierra de Albarracín. These slope deposits have been traditionally considered, without absolute datings, as having been formed during various Pleistocene cold phases. The aim of this paper is to establish the sedimentological, morphological, chronological, and paleoenvironmental characteristics of these deposits through the study of four profiles recorded in the Calomarde canyon (El Rollo, El Molino, and Royuela) and Toril. The most representative profile is that of El Rollo as it is formed by basal tufa and stratified scree layers separated by paleosoils. Radiocarbon datings obtained from paleosoil samples show that the sequence ranges between the early and middle Holocene. The profiles from El Molino and Royuela, as well as the upper levels of Toril, complete the sequence showing deposits from upper Holocene (Bronze Age and ‘Little Ice Age’). These data show the oscillations during the Holocene between colder phases, represented by the stratified screes, and warmer–wetter phases with soil development and local tufa deposits. This geomorphological and pedological response to the Holocene climatic variability shows its clearest records in the canyons. However, there are almost no Pleistocene accumulations – with the exception of that of Toril (minimum age of <43.5 ka BP). The possibility of relating this succession of Holocene environmental changes to known regional and global climatic stages converts these accumulations into the most important Holocene paleoenvironmental record from the Iberian Ranges and the most complete sequence of Holocene stratified screes from the Mediterranean area. [ABSTRACT FROM AUTHOR]

The rocky and indented coast of NW Iberia is characterized by the presence of highly valuable and vulnerable, small and shallow barrier–lagoon systems structurally controlled. The case study was selected to analyse barrier–lagoon evolution based on detailed sedimentary architecture, chronology, geochemical and biological proxies. The main objective is to test the hypothesis of structural control and the significance at regional scale of any high-energy event recorded. This work is also aimed at identifying general patterns and conceptualizing the formation and evolution of this type of coastal systems. The results allowed us to establish a conceptual model of Holocene evolution that applies to rock-bounded barrier–lagoon systems. The initial stage (early Holocene) is characterized by freshwater peat sedimentation and ended by marine flooding. The timing of the marine flooding depends on the relation between the elevation of the basin and the relative mean sea-level position; the lower the topography, the earlier the marine inundation. Thus, the age of basin inundation ranged from 8 to 4 ka BP supporting significant structural differences. Once marine inundation occurred, all systems followed similar evolutionary patterns characterized by a phase of landward barrier migration and aeolian sedimentation towards the back-barrier (i.e. retrogradation) that extended circa 3.5 ka BP. The later phases of evolution are characterized by a general trend to the stabilization of the barriers and the infilling of the lagoons. This stabilization may be temporally interrupted by episodes of enhanced storminess or sediment scarcity. In this regard, washover deposits identified within the sedimentary architecture of the case study explored here suggest pervasive high-energy events coeval with some of the cooling events identified in the North Atlantic during the mid- to late Holocene. [ABSTRACT FROM AUTHOR]