New sedimentological and palynological data from the Permian and Triassic series of the Sancerre-Couy core, Paris Basin, France

Abstract

A new description and sampling campaign of the Sancerre-Couy core has been achieved to reconstruct the evolution of the depositional environments of the Permian and Triassic series and the palynological evolution of the Permian to Lower Jurassic series. High-resolution sequence stratigraphy of the Permian and Triassic series of the Paris Basin, based on well-log analysis, is used to determine seven progradational-retrogradational cycles in the Permian and twelve cycles in the Triassic. Out of the 54 samples collected from the Sancerre-Couy-1 core, only 23 were palynologically productive. Based on the taxonomic composition, four palynological assemblages are distinguished, three of which have been described in previous studies. These three classical palynological assemblages of the Sancerre-Couy-1 core are documented in detail for the first time in this present study. The description of the new assemblage and its correlation can be used to reassess the previously assigned ages: assemblage SC-1 is late Ladinian in age, SC-2 is of the Ladinian–Carnian transition, SC-3 is early Carnian in age, and SC-4 is of late Rhaetian age, whereas it had previously been assigned a Hettangian age.