JpGU-AGU Joint Meeting 2020

Presentation information

[E] Oral

M (Multidisciplinary and Interdisciplinary) » M-IS Intersection

[M-IS14] Evolution of Pelagic Realm

convener:Atsushi Matsuoka(Department of Geology, Faculty of Science, Niigata University), Toshiyuki Kurihara(Graduate School of Science and Technology, Niigata University), Tetsuji Onoue(Department of Earth and Planetary Sciences, Faculty of Science, Kyushu University), XIN LI(State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences)

[MIS14-02] Myr-scale monsoon records paced with Milankovitch cycles during Triassic-Jurassic

*Masayuki Ikeda1, Kazumi Ozaki2, Shintaro Kadoya3 (1.Shizuoka University, 2.Toho University, 3.Washington University)

Earth’s orbital variations on timescales of 104-105 years, known as Milankovitch cycles, have played a critical role in pacing climate change and ecosystem dynamics, through glacial and/or monsoon dynamics. However, the climatic and biotic consequences of these cycles on much longer (~107 years) timescales remain unclear, due to a lack of long proxy records with precise age constraints. Here, we show ~10-Myr scale variations in early Mesozoic (250-180 Ma) records of pelagic biogenic-silica burial flux, atmospheric pCO2, and sea-surface-temperature (SST). Their phase relationships, coupled with carbon cycle modeling results, suggest that orbitally-paced summer monsoon dynamics modulates changes in global weatherability, affecting changes in pCO2 and SST.