Phases of sedimentation and soil formation in SE Spain during the Holocene (Eastern Betic Cordillera)

Abstract

This work gathers the set of available regional geochronological data (14C, Th/U, OSL, TL) on alluvial sediments, calcretes and soils for the semiarid SE Spain to build a theoretical timescale for the most important phases of sedimentation and soil formation occurred in the zone during the Holocene. Most of the data come from the set of paleoseismological and paleoclimatic research in the Murcia–Almería region during the last 15 years. The gathered geochronological data set includes approximately 60 dates, covering the last 11 ka, of which 12 data corresponds to calcretes and carbonate soils. The robust data set of 14C ages allows to construct a detailed ages frequency distribution function discriminating periods (bins) of 500 years. The analysis clearly identifies the climatic events of 8.2 and 2.4 ka, recently considered as GSSP for the Northgrippian and the Meghalayan ages, as drier periods with minor sedimentation, but enhanced calcrete formation, especially the first one. The analysis also identifies the Holocene optimum, as well as the Roman and Medieval warm periods as phases of major sedimentation.