日本地球惑星科学連合2018年大会

講演情報

[EJ] Eveningポスター発表

セッション記号 S (固体地球科学) » S-GL 地質学

[S-GL29] 泥火山と地球化学的・地質地形学的・生物学的関連現象

2018年5月24日(木) 17:15 〜 18:30 ポスター会場 (幕張メッセ国際展示場 7ホール)

コンビーナ:浅田 美穂(国立研究法人海洋研究開発機構)、土岐 知弘(琉球大学理学部)、井尻 暁(国立研究開発法人海洋研究開発機構、共同)、辻 健(九州大学工学研究院)

[SGL29-P03] 西南日本におけるメタン湧水性生物群集

*ジェンキンズ ロバート1 (1.金沢大学理工研究域自然システム学系)

キーワード:methane seep、cold seep、chemosynthetic community

Japanese Islands yield many (more than 80) Cretaceous to Holocene cold-seep communities. Most of them are distributed in central Japan and Hokkaido island, and rare in southwestern Japan although there are relatively many Recent cold-seeps in Nankai Trough region. Recently, several Cenozoic cold-seeps in accretionary complex distributed in Wakayama and Kochi prefectures were investigated. This presentation mainly introduces two cold-seeps; late Eocene to early Oligocene Tanami seep in Kushimoto, Wakayama Prefecture (Amano et al., 2013; PPP) and late Oligocene to early Miocne Mitsu seep in Muroto, Kochi (umpublished data). The Tanami seep was formed during subduction of the Pacific and the Kula plates beneath the Eurasian Plate during the Paleogene (late Eocene to early Oligocene). The Mitsu seep would be formed during subduction of Shikoku Basin ridge. Both seeps are seep-related carbonate blocks with abundant molluscan assemblages including chemosynthetic bivalves, such as vesicomyids, lucinids, thyasirids and solemyids. Those ancient seeps would be important to understand evolution of cold-seep systems in southwestern Japan, including Nankai Trough region.