Comprehensive research on the restoration of scattered high-pressure metamorphic terranes in the Inner Zone of Southwest Japan
西南内带分散高压变质岩体恢复综合研究
基本信息
- 批准号:60302032
- 负责人:
- 金额:$ 3.58万
- 依托单位:
- 依托单位国家:日本
- 项目类别:Grant-in-Aid for Co-operative Research (A)
- 财政年份:1985
- 资助国家:日本
- 起止时间:1985 至 1986
- 项目状态:已结题
- 来源:
- 关键词:
项目摘要
The Sangun metamorphic belt is considered for a long time to be a major coherent glaucophanitic terrane of pre-Jurassic age, and to be paired with the low-pressure Hida metamorphic belt. However, recent studies on geochronology and tectonics have revealed that the belt is in fact comprised of three geologic units of different ages. A tentative threefold division is summarized as follows.1) Around 300 Ma (Carboniferous) group=Northern terrane: This terrane is confined to the northern marginal region (Wakasa, Nagato tectonic zone and Wakamiya) of the "Sangun belt", and corresponds to the western extension of the Hida marginal zone. Each distribution area of this terrane is bounded on adjacent units by distinctive faults and thrusts, and is also characterized by a dominance of serpentinite, metagabbroic and metagranitic rocks, which appear to compose dismembered ophiolite. These ophiolitic rocks have given radiometric ages of 470 to 380 Ma. It is worthy of note that the dates are identica … More l with those of the same kind rocks in the Hida marginal zone.2) Around 220 Ma (Triassic) group=Western terrane: This group occurs in the western region (north Kyushu to Yamaguchi Prefecture) of the "Sangun belt". In the Nishiki-cho area, K-Ar whole rock ages of weakly metamorphosed acidic tuffs are also dated as about 220 Ma, which are identical with Rb-Sr ages for the "Sangun pelitic schists". The acidic tuff and its adjacent siliceous slate yield Permian radiolarians (about 220 Ma). Thus, the 220 Ma would be considered to represent the final phase of the glaucophanitic metamorphism of the western terrane. This is consistent with geologic evidence that the "Sangun metamorphic rocks" are unconformably overlain by the Upper Triassic Mine Group.3) Around 180 Ma (Jurassic) group=Eastern terrane: Younger ages are widespread in the eastern region (Tottori, Okayama and Shimane Prefecture) of the "Sangun belt". In comparison with the western terrane, siliceous metamorphic rocks become conspicuously abundant, and some fensters composed of the equivalents of the Tamba Group are found in this terrane. Recently, Triassic conodonts and Jurassic type radiolarians were obtained from siliceous metamorphic rocks in the Motigase area. These may support a view that the metamorphic rocks of the eastern terrane are younger in age of their deposition as well as in metamorphic age than those of the western terrane. Less
三关变质带长期以来被认为是前侏罗纪时期的一个主要的相干蓝斑岩地体,并与低压Hida变质带相辅相成。然而,最近的地质年代学和构造学研究表明,该带实际上是由三个不同时代的地质单元组成的。一个暂定的三重划分总结如下。1)约300 Ma(石炭系)群=北部地体:该地体局限于“三关带”的北部边缘地区(若坂、长门构造带和若宫),对应于飞驒边缘带的西延。该地体的各个分布区均以断裂和逆冲为界,以蛇纹岩、变质岩和变质岩为主,呈碎裂蛇绿岩状。这些蛇绿岩的辐射年龄为470至380 Ma。值得注意的是,这些日期与Hida边缘带的同类岩石的日期是相同的。2)约220 Ma(三叠纪)组=西部地体:该组产于“三关带”西部地区(九州北部至山口县)。Nishiki-cho地区弱变质酸性凝灰岩的K-Ar全岩年龄约为220 Ma,与“三关泥质片岩”的Rb-Sr年龄一致。酸性凝灰岩及其邻近的硅质板岩产二叠纪放射虫(约220 Ma)。因此,220ma可被认为是西部地体的蓝辉岩变质作用的最后阶段。这与“三关变质岩”被上三叠统矿群不整合覆盖的地质证据是一致的。3)约180 Ma(侏罗纪)群=东部地体:“三关带”东部地区(鸟取、冈山、岛根县)普遍存在较年轻的时代。与西部地体相比,硅质变质岩明显丰富,在该地体中发现了一些与坦巴群相当的溶洞。最近在莫提格斯地区的硅质变质岩中发现了三叠纪牙形刺和侏罗纪型放射虫。这可能支持东部地体的变质岩在沉积年龄和变质年龄上都比西部地体的更年轻的观点。少
项目成果
期刊论文数量(14)
专著数量(0)
科研奖励数量(0)
会议论文数量(0)
专利数量(0)
西村祐二郎: "内帯高圧変成帯 NO.3,NO.4" 西村祐二郎, 49P (,19871986)
西村裕二郎:《内高压变质带NO.3、NO.4》 西村裕二郎,49P (,19871986)
- DOI:
- 发表时间:
- 期刊:
- 影响因子:0
- 作者:
- 通讯作者:
Yujiro NISHIMURA: Yujiro NISHIMURA. High-pressure metamorphic terranes in the Inner Zone, No. 3 & No. 4 (Naitai Kouatu Henseitai), 49 (1986 & 1987)
西村雄二郎:西村雄二郎。
- DOI:
- 发表时间:
- 期刊:
- 影响因子:0
- 作者:
- 通讯作者:
西村祐二郎: International Symposium on Pre-Jurassic East Asia,IGCP Project 224,Reports and Abstracts. 134-138 (1986)
西村裕次郎:前侏罗纪东亚国际研讨会,IGCP 项目 224,报告和摘要 134-138(1986)。
- DOI:
- 发表时间:
- 期刊:
- 影响因子:0
- 作者:
- 通讯作者:
Yukio ISOZAKI: "Early Jurassic radiolarians from bedded chert in Kamiaso, Mino belt, Central Japan" Earth Science (Chikyu Kagaku). 39. 429-442 (1985)
Yukio ISOZAKI:“来自日本中部美浓带 Kamiaso 层状燧石的早侏罗世放射虫”地球科学(Chikyu Kagaku)。
- DOI:
- 发表时间:
- 期刊:
- 影响因子:0
- 作者:
- 通讯作者:
{{
item.title }}
{{ item.translation_title }}
- DOI:
{{ item.doi }} - 发表时间:
{{ item.publish_year }} - 期刊:
- 影响因子:{{ item.factor }}
- 作者:
{{ item.authors }} - 通讯作者:
{{ item.author }}
数据更新时间:{{ journalArticles.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ monograph.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ sciAawards.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ conferencePapers.updateTime }}
{{ item.title }}
- 作者:
{{ item.author }}
数据更新时间:{{ patent.updateTime }}
NISHIMURA Yujiro其他文献
NISHIMURA Yujiro的其他文献
{{
item.title }}
{{ item.translation_title }}
- DOI:
{{ item.doi }} - 发表时间:
{{ item.publish_year }} - 期刊:
- 影响因子:{{ item.factor }}
- 作者:
{{ item.authors }} - 通讯作者:
{{ item.author }}
{{ truncateString('NISHIMURA Yujiro', 18)}}的其他基金
Comparative studies on metamorphic history and tectonic subdivision in Southwest Japan and New Zealand
日本西南部和新西兰的变质历史和构造细分的比较研究
- 批准号:
12640444 - 财政年份:2000
- 资助金额:
$ 3.58万 - 项目类别:
Grant-in-Aid for Scientific Research (C)
Low-grade metamorphism and K-Ar ages of several accetionary complexes in Southwest Japan
日本西南部几个增生杂岩的低级变质作用和 K-Ar 年龄
- 批准号:
07454121 - 财政年份:1995
- 资助金额:
$ 3.58万 - 项目类别:
Grant-in-Aid for Scientific Research (B)
相似海外基金
The study on the possibility of a ultra-high pressure metamorphic belt of the Higo and Kurosegawa Zones in Central Kyushu
九州中部肥后、黑濑川带超高压变质带可能性研究
- 批准号:
17204045 - 财政年份:2005
- 资助金额:
$ 3.58万 - 项目类别:
Grant-in-Aid for Scientific Research (A)