Japan Geoscience Union Meeting 2023

Presentation information

[J] Online Poster

S (Solid Earth Sciences ) » S-VC Volcanology

[S-VC34] Volcanoes in the Sea

Tue. May 23, 2023 1:45 PM - 3:15 PM Online Poster Zoom Room (3) (Online Poster)

convener:Yoshihiko Tamura(Research Institute for Marine Geodynamics, Japan Agency for Maine-Earth Science and Technology), Eisuke Fujita(National research Instituite for Earth science and Disaster Resilience, Volcanic research department), Fukashi Maeno(Earthquake Research Institute, University of Tokyo), Shigeaki Ono(Japan Agency for Marine-Earth Science and Technology)

On-site poster schedule(2023/5/24 17:15-18:45)

1:45 PM - 3:15 PM

[SVC34-P10] Characteristics of rock samples collected from the submarine part of Hunga volcano, Tonga.

*Tomoki Sato1, Yoshihiko Tamura1, Qing Chang1, Richard Wysoczanski2, Kevin Mackay2 (1.Japan Agency for Marine-Earth Science and Technology, 2.National Institute of Water & Atmospheric Research Ltd)

Keywords:Hunga volcano, submarine volcano, dredge

A catastrophic eruption occurred at Hunga volcano on January 15, 2022. This volcano is a large submarine volcano located in the Tonga-Kermadec arc, 65 km north of Tongatapu Island, the capital of Tonga. Part of the caldera rim forms islands at the top of the volcano (Hunga Tonga and Hunga Ha'apai). Older lava collected from the islands are basaltic andesite to andesite [1], but the submarine section has not been previously studied. Recent pyroclastics from the volcano are andesitic in composition [1, 2]. Nishinoshima in the Izu-Ogasawara arc also erupts andesitic magma, and its shape as a submarine volcano is similar. There are several similarities between the two volcanoes. Therefore, the study of Hunga volcano may provide important insights for predicting and preparing for future eruptions of submarine volcanoes in the Izu-Ogasawara arc as well as other similar submarine volcanoes worldwide.
JAMSTEC and NIWA (National Institute of Water and Atmospheric Research Limited) made a Cooperative Research Agreement to collaborate in performing research on the magmatic evolution process of Hunga volcano. The cooperative studies will show the genesis of magmas of this submarine volcano by studying the dredged rocks. NIWA conducted a research cruise 3 months after the 2022 eruption (TAN 2206) and collected a variety of rock samples (lava, pumice, and scoria) from 8 sites (320-1,400 mbsl) on the seafloor around the Hunga volcano. Here we present a summary of the dredge and preliminary results of chemical compositions of the submarine samples as well as bathymetric maps of the edifice.

[1] Brenna et al. (2022) https://doi.org/10.1016/j.lithos.2022.106614
[2] Cronin et al. (2022) https://doi.org/10.5194/egusphere-egu22-13584