日本地球惑星科学連合2023年大会

講演情報

[J] オンラインポスター発表

セッション記号 S (固体地球科学) » S-CG 固体地球科学複合領域・一般

[S-CG52] 海洋底地球科学

2023年5月24日(水) 13:45 〜 15:15 オンラインポスターZoom会場 (6) (オンラインポスター)

コンビーナ:沖野 郷子(東京大学大気海洋研究所)、田所 敬一(名古屋大学地震火山研究センター)

現地ポスター発表開催日時 (2023/5/23 17:15-18:45)

13:45 〜 15:15

[SCG52-P21] Prospecting areas for Mn-Nodules, Co-rich Crust and Gas Hydrates for Deep Sea Mining in Chile: a review

*LUCIA ALEJANDRA VILLAR-MUNOZ1、Masataka Kinoshita2、Joaquim P. Bento3、Nathan Bangs4、Dhugal Lindsay5、Ivan Vargas-Cordero6、Umberta Tinivella6、Michela Giustiniani6、Natsue Abe5、Eduardo Contreras-Reyes1 (1.DEPARTAMENTO DE GEOFISICA, FACULTAD DE CIENCIAS FISICAS Y MATEMATICAS, UNIVERSIDAD DE CHILE, SANTIAGO, CHILE、2.Earthquake Research Institute, the University of Tokyo, Tokyo, 113-0032, Japan.、3.Escuela de Ciencias del Mar, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile. 、4.Institute for Geophysics, Jackson School of Geosciences, The University of Texas at Austin, U.S. 、5.Mantle Drilling Promotion Office, MarE3, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokohama, Japan.、6.Istituto Nazionale di Oceanografia e di Geofisica Sperimentale - OGS, 34010, Trieste, Italy. )

キーワード:gas hydrates, polymetallic nodules, deep sea mining

Chile has a maritory five times larger than its territory. It is one of the Latin American countries with more geophysical and tectonic information about its seabed, motivated mainly by the understanding of the important seismic activity along several geological features and by the subduction of the Nazca plate under the South American plate. Chile includes several features within its exclusive economic zone (EEZ), such as a long submarine trench; submarine ridges (one of them intersecting the continent in front of the central zone and another that has originated from different magma sources); more than one hundred significant seamounts; the Chile Ridge active spreading center; several oceanic fracture zones in the Nazca plate; the downgoing Antarctic plate; an active margin associated with the surface upwelling of colder, nutrient-rich waters that contribute to the formation of new minerals; two microplates; extensive abyssal plains and several submarine canyons in the forearc.

Despite all this variety of geological features, which are often associated with the presence of marine minerals, the mineral and energy resources of the seabed in Chile have not yet been efficiently addressed. This is due to the fact that Chile is the world's largest exporter of copper and other terrestrial mineral resources, downplaying the importance of marine resources.

However, during the last decade, several novel studies showing the extent of gas hydrate reservoir in Chile (from 33-56o S), that serve as an energy resource as well as a source of greenhouse gases, have again attracted the attention of the Chilean scientific community. In this study, we add new seismic images related to a huge hydrate deposit not identified previously. In addition, we present new geological data associated with the presence of polymetallic nodules and cobalt-rich crusts in the Chilean EEZ, which represent the most important but least explored resource of critical elements and base metals in the country, crucial for the production of low carbon energy, electromobility and new technologies.

Furthermore, we compiled diverse geological and geophysical data to elaborate the first review of prospective areas of mineral and energy resources for deep sea mining in the Chilean EEZ, positioning Chile not only as a source of terrestrial minerals, but also as a great source of energy and metals prized by the current industry.