Terrestrial records of two hyperthermal events in the Cretaceous-Paleogene boundary suggest different control mechanisms

Two hyperthermal events with different carbon cycle perturbations occurred across the Cretaceous-Palaeogene boundary, i.e., the late Maastrichtian Warming Event and the Early Danian Dan-C2 event. This study uses a terrestrial δ¹³Ccarb record from the Nanxiong Basin (southeastern China) to compare with marine records. The results indicate that the Dan-C2 event exhibits typical hyperthermal characteristics, while the late Maastrichtian Warming Event shows a more muted and prolonged δ¹³C excursion. The absence of short-eccentricity cycles in the marine record during the late Maastrichtian Warming Event suggests Deccan volcanism's influence on the carbon cycle, whereas the Dan-C2 event shows less volcanic perturbation, implying different control mechanisms for these two events.

Mingming Ma, Mengdi Wang, Huixin Huang, Xiuming Liu