Chronostratigraphy and Paleoclimatology of the Lodève Basin, France: Evidence for a pan-tropical aridification event across the Carboniferous–Permian boundary

Abstract

a b s t r a c tPaleosols preserved within the Carboniferous-Permian succession of the Lodève Basin, Massif Central, France change stratigraphically from Histosols to calcic Vertisols and Calcisols to gypsic Vertisols and ultimately back to calcic Vertisols and Calcisols. New high-precision U-Pb zircon ages (CA-IDTIMS) for tuff beds within the Lodève and adjacent Graissessac basins significantly revise the chronostratigraphy of these and correlated Permian terrestrial basins of eastern Euramerica. Under the newly revised chronostratigraphy presented here these stratigraphic changes in morphology indicate a substantial drying of paleoenvironments across the Carboniferous-Permian boundary with a trend toward progressively more arid and seasonal climates through most of the early Permian. This newly-realized chronology provides a paleoenvironmental and paleoclimatic timeline for eastern tropical Pangea that is contemporaneous with similar records in western Pangea and suggests pantropical, progressive climate change toward aridity and seasonality occurred from the Late Carboniferous through early Permian.

Aridification across the Carboniferous–Permian transition in central equatorial Pangea: The Catalan Pyrenean succession (NE Iberian Peninsula)

“…Both French and Catalan ichnoassemblages display the same ichnotaxa (Gand, 1988;Gand and Durand, 2006;Mujal et al, 2016a). More tentatively, Hyloidichnus is only found in the upper ichnoassociation of Les Esglésies (Mujal et al, 2016a), and the lower appearance of this ichnotaxon in the Lodève Basin is at the Rabejac Fm (Gand and Durand, 2006), aged early-middle Artinskian (Michel et al, 2015).…”

“…By contrast, few regions have been analyzed in equivalent latitudes from Central Pangea. Such regions include central and eastern Europe Eros et al, 2012;Opluštil et al, 2013Opluštil et al, , 2017a) and the French Lodève Basin Lopez et al, 2008;Michel et al, 2015Michel et al, , 2016. In fact, C-P terrestrial successions of southwestern Europe (Western Tethys or eastern equatorial Euramerica) are mostly characterized by large stratigraphic hiatuses, both due to erosion and/or lack of sedimentation (Cassinis et al, 2013;Gretter et al, 2015).…”

“…290 Ma (Michel et al, 2015). Both French and Catalan ichnoassemblages display the same ichnotaxa (Gand, 1988;Gand and Durand, 2006;Mujal et al, 2016a).…”

Re-assessment of lithostratigraphy, biostratigraphy, and volcanic activity of the Late Paleozoic Intra-Sudetic, Krkonoše-Piedmont and Mnichovo Hradiště basins (Czech Republic) based on new U-Pb CA-ID-TIMS ages

“…Although these data are still relatively rare, where available, they help to calibrate local lithostratigraphic units, identify hiatuses, and via numerical ages correlate local lithostratigraphic units and biozones to Global Chart (e.g. Davydov et al 2010, Pointon et al 2012, Schmitz & Davydov 2012, Michel et al 2015, Opluštil et al 2016. Such an approach can be very useful in continental basins, where floral and faunal biozones are difficult to correlate to marine zones and, in turn, to global stages.…”

New material of Alierasaurus ronchii (Synapsida, Caseidae) from the Permian of Sardinia (Italy), and its phylogenetic affinities

“…Caseids, together with the varanopids, represent one of two primitive clades that co-exist with the more derived therapsid synapsids (Dilkes and Reisz, 1996;Reisz and Laurin, 2001;Maddin et al, 2008;Reisz and Fröbisch, 2014). The youngest known occurrence of caseids may be represented by a still undescribed large caseid from the La Lieude Formation of the Lodève Basin, a rock unit tentatively assigned to an early Lopingian age by some authors (Schneider et al, 2006;Lopez et al, 2008) while other authors ascribe this formation to the Wordian (Gand and Durand, 2006;Michel et al, 2015).…”