Late Pleistocene to recent climate change in Córdoba Province, Argentina: Geomorphological evidence

Abstract

Abstract Repeated episodes of climate change affected the Cordoba Plains during the Late Pleistocene and Holocene. Many of the geomorphologic features of Cordoba Province were developed in response to climatic oscillations, and their development can be correlated to changes in precipitation and hydrologic regimes. Alternating periods marked by dry climate and high evapotranspiration rates were interspersed with more humid intervals, and can be correlated using stratigraphic and geomorphic evidence at the regional level. The initial phase of the Late Pleistocene was characterized by significant loess deposition and the formation of large alluvial fans. These sediments and landforms are representative of a dry climate. The transition to the Late Pleistocene was marked by the initiation of a humid climate regime, giving rise to enhanced fluvial activity and sedimentation, expansion and integration of drainage networks, and development of paludal areas and successions. Pedogenesis occurred in the interbasin areas, involving precipitation of silica and sesquioxides. During Latest Pleistocene–Early Holocene time, coinciding in part with the ‘Last Glacial Maximum’, a dry and cool climate resulted in widespread aeolian sand and loess deposition. The Early to Mid-Holocene was characterized by humid subtropical conditions which became established throughout the region, accompanied by pedogenic development of profiles with prominent Bt horizons, and further modification of drainage networks. During the Mid to Late Holocene, these warm and humid conditions were replaced by a semiarid climate, resulting in widespread aeolian deposition. Wind action formed deflation hollows and dune fields in several areas. The climate reverted to subhumid and temperate conditions during the latter part of the Late Holocene, and small areas of wetlands developed. The Little Ice Age was marked by climatic deterioration, and the deposition of a thin layer of aeolian sediment. The current climate of Cordoba is subhumid and temperate.