Paleosols are stratigraphic tools of great importance in the study of continental basins. Unlike in large-scale marine basins, where there is good knowledge of the factors that control its filling, in continental setting there is a complex and high-frequency interplay among accommodation, deposition, and erosion, and a major influence of the climate in the rate of the sediment and water supply from sources to the basin. The development of soils is directly related to climate, vegetation, parent material, topographic relief, and time of development, which may be useful to describe alternating phases of active tectonic and quiescence. Paleosols stand out in paleoclimatic interpretations and high-frequency climatic changes have been described based on their study. In strongly deformed basins, the differentiation between lithostratigraphic units with very similar facies but different ages may be problematic. In those cases, paleosols are a good distinguishing criterion because they are very sensitive to climatic and topographic changes. In the Southern border of the Pyrenees, Permian-Triassic terrestrial red-beds were deposited in discontinuous sub-basins affected by tectonic activity contemporaneous with the sedimentation that generated internal unconformities of different order. Subsequent Alpine tectonic inversion greatly affected the configuration of the basins, adding complexity to its study. In this work, the paleosols observed in the field were described, classified, and interpreted in order to study the link between pedogenesis and the evolution of the landscape under certain tectonic and palaeoclimatic conditions. Grouped into palaeocatenas, the lateral variation of pedotypes across the landscape is useful to interpret topography and water table variations, which can be explained taking into account large-scale variations of climate, accommodation, and sedimentary supply. The study of hydrological and climatic conditions was complemented with the identification of the mineralogical composition of the parent material and δ13C and δ18O isotopic signatures from inorganic pedogenic carbonate of paleosols and lacustrine limestones. The continental Permian and Triassic basins of western Europe are strongly disconnected and characterized by several hiatuses. The results provided here can be useful to improve the knowledge of the tectonic and palaeoclimatic conditions of the western Tethys during the first stages of Pangea break-up.
Permian and Triassic paleosols in the fluvial-lacustrine record of the central Pyrenees Basin, Spain: A stratigraphic tool for interpreting syn-tectonic sedimentary evolution and paleoclimate.
Lloret Quirante Joan;Gretter Nicola;Ronchi Ausonio
2021-01-01
Abstract
Paleosols are stratigraphic tools of great importance in the study of continental basins. Unlike in large-scale marine basins, where there is good knowledge of the factors that control its filling, in continental setting there is a complex and high-frequency interplay among accommodation, deposition, and erosion, and a major influence of the climate in the rate of the sediment and water supply from sources to the basin. The development of soils is directly related to climate, vegetation, parent material, topographic relief, and time of development, which may be useful to describe alternating phases of active tectonic and quiescence. Paleosols stand out in paleoclimatic interpretations and high-frequency climatic changes have been described based on their study. In strongly deformed basins, the differentiation between lithostratigraphic units with very similar facies but different ages may be problematic. In those cases, paleosols are a good distinguishing criterion because they are very sensitive to climatic and topographic changes. In the Southern border of the Pyrenees, Permian-Triassic terrestrial red-beds were deposited in discontinuous sub-basins affected by tectonic activity contemporaneous with the sedimentation that generated internal unconformities of different order. Subsequent Alpine tectonic inversion greatly affected the configuration of the basins, adding complexity to its study. In this work, the paleosols observed in the field were described, classified, and interpreted in order to study the link between pedogenesis and the evolution of the landscape under certain tectonic and palaeoclimatic conditions. Grouped into palaeocatenas, the lateral variation of pedotypes across the landscape is useful to interpret topography and water table variations, which can be explained taking into account large-scale variations of climate, accommodation, and sedimentary supply. The study of hydrological and climatic conditions was complemented with the identification of the mineralogical composition of the parent material and δ13C and δ18O isotopic signatures from inorganic pedogenic carbonate of paleosols and lacustrine limestones. The continental Permian and Triassic basins of western Europe are strongly disconnected and characterized by several hiatuses. The results provided here can be useful to improve the knowledge of the tectonic and palaeoclimatic conditions of the western Tethys during the first stages of Pangea break-up.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.