Anomalous weathering records in the Cleveland Basin (Yorkshire, UK) during the T‐OAE global warming

Abstract

Early Toarcian (~183 Ma) was marked by a global warming event which accelerated continental chemical weathering. To constrain the early Toarcian weathering intensity of a Cleveland Basin (Yorkshire, UK) region, this study employed its sediment chemical weathering proxies (potassium/aluminium (K/Al) and K/rubidium (K/Rb)). The K/Al and K/Rb exhibit an anomalous chemical weathering intensity signal from the contemporaneous warm, moist world. Variations in weathering intensity for the Yorkshire section inversely comply with detrital grain size changes (indicated by Al/silicon (Al/Si)). This finding implies that continental chemical weathering did not play a major role in changing detrital grain sizes in the Yorkshire sediments. Instead, short‐term sea‐level changes in the Cleveland Basin can explain the stratigraphic variations in detrital grain sizes. Anomalies of geochemical proxies for chemical weathering and eustatic sea‐level changes do exist at local scales possibly driven by Milankovitch cycle, which reminds us to be more careful when reconstructing palaeoclimate states.