Terrestrial paleoclimate transition associated with continental weathering and drift during the Aptian-Albian of East Asia

Reconstruction of Aptian-Albian paleocli-mate obtained from marine records remains a challenging topic, but studies on coeval ter-restrial paleoclimate and trigger mechanisms have lagged substantially. In this study, new multiproxy data from mudrocks in the Fuxin Basin of NE China provide a high-resolution terrestrial climate record from East Asia. Here, we demonstrate the occurrence of ter-restrial climate cooling during the late Aptian (118-113 Ma), which interrupted the mid -Cretaceous warming shown in global records. Nearly uniform long-term global climate trends attributable to tectonism, volcanism, and weathering occur in Early Cretaceous terrestrial and marine records. In the Fuxin Basin, the long-term terrestrial climate was characterized by increasing temperatures during the late early Aptian, gradual cool-ing during the late Aptian, and subsequent enhanced warming during the early Albian. Moreover, chemical weathering and humid-ity during these intervals were low, moderate to high, and then moderate, respectively. A markedly reduced high-elevation paleogeo-morphology under strong continental weath-ering during the late Aptian increased the variability in chemical weathering fluxes as the Eurasian plate in NE China drifted SE during the Early Cretaceous and then NE during the Late Cretaceous. We suggest that a combination of enhanced continental weathering and weakened plate drift induced changes in atmospheric CO2, while the geo-graphic setting ultimately led to cooling in the Fuxin Basin during the late Aptian. Our results illustrate the importance of exploring long-term tectonic-climatic-biotic feedbacks to improve our understanding of tectonic processes and ecological transitions across various spatiotemporal scales.

Automated summary

In this study, new data from mudrocks in the Fuxin Basin of NE China provide a high-resolution terrestrial climate record from East Asia during the late Aptian to early Albian. The results show a cooling period during the late Aptian, breaking the trend of global warming in the mid-Cretaceous. The study suggests that enhanced continental weathering and weakened plate drift induced changes in atmospheric CO2, leading to the cooling climate in the Fuxin Basin.