講演情報
[MZZ49-04]Pushing the Frontier of Earth’s Deep-Time CO2 Reconstructions
*Hana Jurikova1、Ross Whiteford2、Molly Trudgill3、Lucia Angiolini4、James W.B. Rae1 (1.University of St Andrews, UK、2.Royal Holloway University of London, UK、3.Laboratoire des Sciences du Climat et de l'Environnement (LSCE), France、4.University of Milan, Italy)
キーワード：
atmospheric CO2 and ocean pH、boron isotopes、brachiopods、mass extinctions、Earth's deep-time carbon cycle、palaeoceanography and palaeoclimatology
Atmospheric CO2 and ocean pH records derived from the boron isotope composition of foraminifers’ shells have, over the last couple of decades, revolutionised our understanding of the Cenozoic (~66 million years) carbon cycle. However, deeper-time reconstructions have generally been regarded as controversial due to difficulties in interpreting the rock record, including disentangling secondary influences and the lack of constraints on ancillary parameters required to calculate CO2 from boron isotopes. Here, we will summarise recent advances in boron isotope analysis and their application to brachiopods, which now allow robust CO2 and climate reconstructions to be extended further back in time to the emergence of complex multicellular life on Earth (~500 million years ago). By showcasing new Palaeozoic and Mesozoic boron isotope records, we will explore the role of CO2 in driving Earth’s major climate transitions and mass extinctions. These advances push the frontier of Earth’s deep-time CO2 reconstructions, providing unprecedented insight into the role of CO2 in environmental, biotic, and climatic change - past, present, and future.