沈み込み帯火山活動

スポンサーリンク

概要

• 論文の詳細を見る

• Subduction zone magmatism can be subdivided into three categories based on the difference in the depth of the original mantle activity responsible for the upwelling and the subsequent melting of mantle materials ; arc magmatism (<200 km depth), backarc intraplate magmatism (〜650 km), and superplume magmatism (〜2900 km). Physical and geochemical characteristics of arc magmatism may be largely explained by migration of H_2O associated with dehy dration/hydration reactions taking place both in the subducted slab and the downdragged portion of the mantle wedge. Backarc intraplate magmatism typically occurring in NE China-Far East Russia behind the Japanese arc-trench system may be the surface manifestation of the upwelling of harzburgitic materials which formally compose the residual peridotite portion of the oceanic lithosphere and less dense than the surrounding upper mantle materials. Partial melting of such a depleted plume with a certain degree of entrainment of an enriched subcontinental mantle material may be consistent both with the trace element and isotope compositions of those intraplate lavas. Ocean island hotspot lavas from S. Pacific and S. Atlantic are distinct in that those magmas tap a source which is 1) more fertile and more enriched in basaltic component and 2) higher in U/Pb ratios than other normal hotspot lavas than the normal hotspot source. Those magmas also have higher Nb/Zr ratios, suggesting the melting process in the presence of silicate perovskite in the lower mantle. Whole-mantle-scale recycling of the basaltic oceanic crust may contribute to forming such characteristic OIB magmas.

• 特定非営利活動法人日本火山学会の論文
• 1997-04-25

著者

• 巽 好幸

  School Of Earth Sciences Ihs Kyoto University

• 荒井 里栄子

  Graduate School of Human and Enviromental Studies, Kyoto University

• 小木曾 哲

  Department of Earth and Planetary Sciences, Tokyo Institute of Technology

• 荒井 里栄子

  Graduate School Of Human And Enviromental Studies Kyoto University

• 小木曾 哲

  Department Of Earth And Planetary Sciences Tokyo Institute Of Technology

関連論文

• A1 インド洋、レユニオン島及びモーリシャス島の火山学的意義とその予備調査 (1994)
• 322. インド洋ホット・スポットとしてのレユニオン島の地学的意義とその予備的調査(1994)
• WG3:巨大海台掘削計画--地球システム変動予測をめざして (総特集 21世紀の深海掘削への展望--ODPからOD21へ) -- (2部 21世紀の深海掘削への展望--OD21)
• 沈み込み帯火山活動
• 7. 島弧マグマの発生 : 島弧中央部と会合部
• 桜島・沖小島流紋岩 -K-Ar年代および岩石学的特徴-
• B37 浜田産メリライトーオリビンネフェリナイト
• 沈み込み帯オフィオライトの成因 (オフィオライト)
• 沈み込み帯における玄武岩質マグマの発生--1983年以降のモデル (故坪井誠太郎先生追悼講演会要旨)
• G37 浜田ネフェリナイトの成因 : 交代作用を受けたマントル起源
• ス-パ-プル-ムの起源と活動史をさぐる

もっと見る 閉じる

スポンサーリンク