火山弧深部におけるマグマ過程,日高変成帯主帯を例として

火山弧深处的岩浆过程，以日高变质带为例

• 批准号: 06740393
• 负责人: 大和田 正明
• 金额: $ 0.77万
• 依托单位: Yamaguchi University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Encouragement of Young Scientists (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 无数据
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06740393/
• 关键词: 下部地殻; 深成複合岩体; 火山弧深部相

下部地殻条件のもとで固結した深成複合岩体を火山弧深部相の化石とみなし,マントル起源の玄武岩質マグマと下部地殻の相互作用を直接観察することは,高温型変成帯における変成作用の熱源を明らかにできる.また,同時にマグマ過程の解明にも貢献できる.下部地殻の断片が露出している日高変成帯主帯において,下部地殻の部分溶融による花崗岩質マグマとマントル起源の玄武岩質マグマの相互作用に着目し,変成岩類と火成岩類との地質学的・岩石学的関係を解明するする目的で今年度の研究に取り組んだ.対象とした地域は,日高変成帯主帯のうち比較的露出条件がよく,各種岩石が分布する南部地域である.その結果以下の点が明らかになった.1.日高変成帯主帯南部地域は,主に深成岩類と泥質・砂質変成岩類から構成される.2.本地域の地質構造は,基本的に低角度の衝上断層によるナップ構造が卓越する.これにより,地殻深部物質が地表部に上昇してきた.しかし,今までほとんど見逃されてきた低角の正断層が初生的な地質の累重構造に貢献している.また,変成帯の上昇に関連した衝上断層の一部は,体角度正断層を切っている.3.深成岩類の活動は,少なくとも2回のステージに区分される.早期のものは,グラニュライト相変成作用を被り,周囲の変成岩類と類似する面構造や線構造を持つ.この期の岩石は,上述した低角度の正断層によって切られている.後期のものは,早期のものに比べ変形の程度が弱いかほとんど認められず,上記の衝上断層を切るものもある.4.早期に属する塩基性岩類は,N-MORB的な組成を示すのに対し,後期のそれは島弧的な組成を示す.また,後期岩石のRb-Sr全岩鉱物アイソクロン年代は18Maを示す.

In the lower part of the earth, the condition, the solid, the plutonic complex rock mass, the volcanic arc deep facies, the fossil, the origin, the basalt, the lower ground, the interaction, the high-temperature type, the origin, the origin, the interaction, and the high temperature type. Thank you, and at the same time, we will explain the process and offer your thanks. The fragments of the lower terrane reveal that the height of the lower part of the earth is higher than the other, and the lower part of the earth is partially melted, the origin of the basalt, the origin of the basalt, the interaction of basalts, the understanding of petrology of diagenetic igneous rocks and geochemistry, the purpose of this year's study is to learn from this year's research. For example, the solar height becomes the exposure condition of the main weather area, and all kinds of rocks are distributed in the southern region. The results show that the following information is clear. 1. The sun-high climate dominates the southern region, which is dominated by deep diagenetic rocks, mud sand, diagenetic sand and diagenetic rocks. 2. The local area is built on the ground, and the basic "low angle" is used to create "excellence". The ground is deep, the surface is deep, and the ground is deep. Today, I am trying to escape from the low angle, which is cutting off the newborn land. The angle of the body is cut off, and the angle is cut off. 3. The activity of deep diagenetic rocks is less than 2 times higher than that of other rocks. In the early stage, the system was affected by each other, and the type of diagenesis was similar to that of the production line. During the period of rock, the above-mentioned "low angle" is broken and cut. In the later period, it was weaker than the shape in the early stage, and it was cut off in the upper stage. 4. In the early stage, it belongs to the basic rock type, the composition of the N-MORB shows the composition of the basic rock, and the composition of the later arc shows the composition of the arc. In the later period, the whole rock Rb-Sr shows the age of the whole rock and the age of the 18Ma.

项目成果

小山内康人: "日高変成帯における高温変成作用と地殻溶融" 地質ニュース. 478号. 34-44 (1994)

小山内泰人：“日高变质带的高温变质作用和地壳熔融”，《地质新闻》第478期。34-44（1994）。