AUTHOR=Sakata Shoko , Inoue Mayuri , Tanaka Yasuaki , Nakamura Takashi , Sakai Kazuhiko , Ikehara Minoru , Suzuki Atsushi 

TITLE=Assessment of chemical compositions in coral skeletons (Acropora digitifera and Porites australiensis) as temperature proxies

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 11 - 2024

YEAR=2024

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2024.1329924

DOI=10.3389/fmars.2024.1329924

ISSN=2296-7745

ABSTRACT=Although biogenic carbonates, such as foraminifera and coccolithophorids, are valuable tools for reconstructing past environments, scleractinian corals also offer environmental data from tropical to subtropical regions with a higher time resolution. For example, oxygen isotopes (δ 18 O) and strontium-calcium (Sr/Ca) ratios have been utilized to reconstruct sea surface temperatures and salinity, primarily through the use of massive-type Porites sp. from the Pacific, as well as corals like Diploria and Montastrea from the Atlantic. While a few types of corals other than Porites have been utilized in paleoclimate studies, comprehensive evaluations of their geochemical tracers as temperature proxies have not been thoroughly conducted. Therefore, in this study, we focused on branching-type Acropora, which are found worldwide and are often present in fossil corals. We conducted a comparison of the chemical compositions (δ 18 O, δ 13 C, Sr/Ca, U/Ca, Mg/Ca, and Ba/Ca) of Acropora digitifera and Porites australiensis through temperature-controlled culture experiments.