Revisiting the Permian Stratigraphy of the Kuznetsk Coal Basin Using Radioisotopic Data: Sedimentology, Biotic Events, and Palaeoclimate

Radioisotopic dating of five stratigraphic levels within the Permian succession of the Kuznetsk Coal Basin refines the ages of the corresponding stratigraphic units and, for the first time, enables their direct correlation with the International Chronostratigraphic Chart (2024). The analysis reveals significant discrepancies between the updated ages and the previously accepted regional scheme (1982–1996). A comparison of the durations of regional stratigraphic units with estimated rates of coal and siliciclastic sediment accumulation indicates that the early Permian contains the most prolonged stratigraphic hiatuses. The updated stratigraphic framework enables a re-evaluation of the temporal sequence of regional sedimentological, volcano-tectonic and biotic events, allowing for more accurate comparison with the global record. Palaeoclimate reconstructions indicate that during the early Permian, the Kuznetsk Basin was characterised by a relatively warm, humid, and aseasonal climate, consistent with its mid-latitude position during the Late Palaeozoic Ice Age. In contrast, the middle to late Permian shows a transition to a temperate, moderately humid climate with pronounced seasonality, differing from the warmhouse conditions of low-latitude palaeoequatorial regions. The latest Lopingian reveals a distinct trend toward increasing dryness, consistent with global palaeoclimate signals associated with the end-Permian crisis.