[U-03] Advanced understanding of Quaternary and Anthropocene hydroclimate changes in East Asia

[U03-01] A rapid increase in anthropogenic fingerprints in the Beppu Bay stratigraphy as a potential marker of the onset of the Anthropocene

★Invited Papers

*Michinobu Kuwae¹, Bruce P. Finney², Zhiyuan Shi³, Aya Sakaguchi³, Narumi Tsugeki⁴, Takayuki Omori⁵, Tetsuro Agusa⁶, Yoshiaki Suzuki⁷, Yusuke Yokoyama⁵, Hirofumi Hinata¹, Yoshio Hatada¹, Jun Inoue⁸, Kazumi Matsuoka⁹, Misaki Shimada¹⁰, Hikaru Takahara¹⁰, Shin Takahashi¹, Daisuke Ueno¹¹, Atsuko Amano⁷, Jun Tsutsumi³, Masanobu Yamamoto¹², Keiji Takemura¹³, Keitaro Yamada¹⁴, Ken Ikehara⁷, Tsuyoshi Haraguchi¹⁵, Stephen Tims¹⁶, Michaela Froehlich¹⁶, L. Keith Fifield¹⁶, Takahiro AZE⁵, Kimikazu Sasa³, Tsutomu Takahashi⁵, Masumi Matsumura³, Yukinori Tani¹⁷, Peter R. Leavitt¹⁸, Hideyuki Doi¹³, Tomohisa Irino¹², Kazuyoshi Moriya¹⁹, Akira Hayashida²⁰, Kotaro Hirose²¹, Hidekazu Suzuki²², Yoshiki Saito²³ (1.Ehime Univ., 2.Idaho State Univ., 3.University of Tsukuba, 4.Matsuyama University, 5.The University of Tokyo, 6.Prefectural University of Kumamoto, 7.National Institute of Advanced Industrial Science and Technology, 8.Osaka Metropolitan University, 9.Nagasaki University, 10.Kyoto Prefectural University, 11.Saga University, 12.Hokkaido University, 13.Kyoto University, 14.Ritsumeikan University, 15.Osaka City University, 16.The Australian National University, 17.University of Shizuoka, 18.University of Regina, 19.Waseda University, 20.Doshisha University, 21.University of Hyogo, 22.Tokyo University of Marine Science and Technology, 23.Shimane University)

Keywords:Anthropocene, GSSP, Beppu Bay, anthropogenic fingerprints, Great Accelelation

‘Great Acceleration’ has been a convincing rationale of the start of an Anthropocene epoch because of the intensity, magnitude, planetary significance, and global isochroneity (Waters et al., 2022). While there are diverse proxy records that support impacts of the Great Acceleration on the geological environments around the mid-20th century, they show diachronous timings not only between the different proxy-based anthropogenic events but also between sites for the same proxy. Therefore, the onset of the Great Acceleration seen in the geological strata still remains to be well-defined. It also remains unclear whether or not a rapid increase in plutonium, which is considered a primary marker of the start of the Anthropocene, is consistent with a geological marker of the onset of the Great Acceleration. Here we present cumulative numbers of the anthropogenic fingerprints in the Beppu Bay sediments, which were detected from 57 proxies (Kuwae et al., 2022). An explosion of the number of fingerprints in the Beppu Bay stratigraphy could detect the impacts of intensified human activities on the geological environments and produce a simple and reasonable geological marker of the onset of the Great Acceleration. An explosion of the anthropogenic fingerprints was detected at the 1953 CE level (64.6 cm depth in the master core, a candidate for the Anthropocene GSSP), at which radioactivity of ^239+240Pu starts abruptly increasing (Kuwae et al., 2022). This result supports that the plutonium signature is suitable as the onset of the Great Acceleration and the Anthropocene.

References
Kuwae, M., Finney, B., Shi, Z., Sakaguchi, A., Tsugeki, N., Omori, T., Agusa, T., Suzuki, Y., Yokoyama, Y., Hinata, H., Hatada, Y., Inoue, J., Matsuoka, K., Shimada, M., Takahara, H., Takahashi, S., Ueno, D., Amano, A., Tsutsumi, J., Yamamoto, M., Takemura, K., Yamada, K., Ikehara, K., Haraguchi, T., Tims, S., Froehlich, M., Fifield, L.K., Aze, T., Matsumura, M., Takahashi, T., Sasa, K., Tani, Y., Leavitt, P.R., Doi, H., Irino, T., Moriya, K., Hayashida, A., Hirose, K., Suzuki, H. and Saito, Y. (2022) Beppu Bay, Japan, as a candidate Global boundary Stratotype Section and Point for the Anthropocene series. The Anthropocene Review. https://doi.org/10.1177/20530196221135077
Waters, C.N., Williams, M., Zalasiewicz, J., Turner, S.D., Barnosky, A.D., Head, M.J., Wing, S.L., Wagreich, M., Steffen, W., Summerhayes, C.P., Cundy, A.B., Zinke, J., Fiałkiewicz-Kozieł, B., Leinfelder, R., Haff, P.K., McNeill, J.R., Rose, N.L., Hajdas, I., McCarthy, F.M.G., Cearreta, A., Gałuszka, A., Syvitski, J., Han, Y., An, Z., Fairchild, I.J., Ivar do Sul, J.A. and Jeandel, C. (2022) Epochs, events and episodes: Marking the geological impact of humans. Earth-Science Reviews 234:104171.