A Carbon Isotopic Stratigraphic Pattern of the Late Palaeozoic Coals in the North China Platform and Its Palaeoclimatic Implications

Abstract This paper gives the stable carbon isotopic data in coals from the Late Namurian to Kazanian stages in the Serteng Mt., Xishan and Huainan coalfields of the North China Platform. Its stratigraphic pattern shows that several isotopic shifts are apparent, and the large δ¹³C negative shifts (approximately 2.5 to 3.0 %%) occurred during the Stephanian, Artinskian and Kazanian are observed in three Permo-Carboniferous coalfields. Those negative shifts are neither related to the coal rank and coal macerals, nor caused by the variety of peat-forming plants. The general decrease in the δ¹³C values of the Stephanian, Artinskian and Kazanian coals is consistent with an overall decrease in the δ¹³C values of ambient atmospheric CO₂ and/or a relative increase in atmospheric P_co2 during the coal-forming periods. Therefore the authors postulate that the oxidation of peat, and the δ₁₃C-depleted CO₂ flux into the atmosphere during the above stages may have contributed to coeval palaeoclimatic warming by way of the greenhouse effect.