Geochronology and tectonics of the Tien-Shan Mountains in the Athashy and Aktyuz areas, Kyrgyzstan

吉尔吉斯斯坦阿塔什和阿克图兹地区天山山脉的地质年代学和构造

• 批准号: 17340149
• 负责人: TAKASU Akira
• 金额: $ 9.33万
• 依托单位: Shimane University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2005
• 资助国家: 日本
• 起止时间: 2005 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-17340149/
• 关键词: metamorphic geology; Tien-Shan Mountains; geochronology; tectonics; zircon; monazite; Sambagawa metamorphic belt; 三波川変成岩

(1)The clasts of glaucophane eclogites were newly found from a conglomerate bed tectonically overlying on the regional eclogite formation (Choloktor Formation) in the Atbashy area The eclogites in the Choloktor Formation ware crystallized thorn the conditions of the glaucophane schist fides to the eclogite facies (>15kb, 500-560℃). The eclogites from the conglomerate have experienced two events of high pressure type metamorphism, ie. metamorphismform to form. eclogite (>15 kb, 490-590℃) and metamorphism from the glaucophane schist facies to the epidote amphibolite fades. These suggest that there are at least two tectonic and metamorphic events of eclogite formation in the Paleozoic Southern Tien-Shan .(2) Coesites have been newly described from talc-garnet-chloritoid schists and quartzites in the Makbal area. This suggests that the matrix metamorphic rocks of the eclogite blocks are suffered UHP metamorphism.(3) The metamorphic conditions of the eclogites form the Neldy Formation and Makbal Formation are >12 kb, 480-570℃ and >15 kb, 540-620℃, respectively. Both eclogites were suffered prograde metamorphism of the epidote amphibolite facies and the glaucophane schist facies, respectively.(4) Monazite separated from the talc-garnet-chloritoid schists were dated by COME U-Pb method, and the ages of the monazite are 480 Ma The ages of the monazites in garnet porphyroblasts were also measured and the ages are the same as those of separated monazites, 480 Ma is the age of the UHF metamorphism in the Makbal area. The K-Ar ages of biotite schists and amphibolites are 769 Ma and 881 Ma, respectively and they are older than the age of the UHP metamorphism.(4) Eclogites in the Aktyuz area experienced the amphibolite to granulite facies metamorphism (4-10 kb, 560-660℃) before the eclogite metamorphism (15-25 kb, 600-710℃), suggesting a metamorphism of inception of subduction event.

(1)阿特巴什地区区域性榴辉岩组(Choloktor组)上构造上覆的砾岩层中新发现了蓝闪石榴辉岩碎屑。Choloktor组中的榴辉岩结晶将蓝闪石片岩的条件刺入了榴辉岩相(>15kb, 500-560℃）。砾岩中的榴辉岩经历了两次高压型变质作用，即：变质形成。榴辉岩（>15 kb，490-590℃）和从蓝闪石片岩相到绿帘角闪岩的变质作用。这表明古生代南天山至少存在两次榴辉岩形成的构造和变质事件。(2)在马克巴尔地区的滑石-石榴石-绿泥石片岩和石英岩中新发现了柯石英。这表明榴辉岩块体的基质变质岩发生了超高压变质作用。(3)Neldy组和Makbal组榴辉岩的变质条件分别为>12 kb, 480~570℃和>15 kb, 540~620℃。两种榴辉岩分别经历了绿帘角闪岩相和蓝绿石片岩相的前变质作用。(4)从滑石-石榴石-绿泥石片岩中分离出独居石，采用COME U-Pb法测年，独居石年龄为480 Ma。同时测定了石榴石成斑细胞中独居石的年龄，为 与分离的独居石相同，480Ma是Makbal地区超高频变质作用的年龄。黑云母片岩和角闪岩的K-Ar年龄分别为769 Ma和881 Ma，均早于超高压变质作用的年龄。(4)阿克图兹地区榴辉岩在榴辉岩变质作用(15-25 kb， 600-710℃），表明俯冲事件开始时发生变质作用。

项目成果

Polymetamorphism of Aktyuz eclogites (northern Kyrgyz Tien-Shan) deduced from inclusions in garnets.

从石榴石中的包裹体推断出阿克图兹榴辉岩（吉尔吉斯天山北部）的多变质作用。

• 发表时间: 2007
• 期刊: Journal of Mineralogical and Petrological Science 102
• 作者: Orozbaev;R.T.;Takasu;A.;Tagiri;M.;Bakirov;A.B.;Sakiev;K. S.
• 通讯作者: K. S.

熱年代学データに基づく日高山脈の上昇史.

基于热年代学数据的日高山脉隆起历史。

• 发表时间: 2006
• 期刊: 地質学雑誌 112
• 作者: Kasahara;J.;三好建正;川上源太郎.大平寛人・.有田一則・板谷徹丸・川村信人
• 通讯作者: 川上源太郎.大平寛人・.有田一則・板谷徹丸・川村信人

Distribution of Fe2+ in a synthetic (Ca, Na)2(Mg, Fe2+)Si207-melilite : 57Fe Mossbauer and X-ray Rietveld studies

Fe2 在合成 (Ca, Na)2(Mg, Fe2 )Si2O7-黄长石中的分布：57Fe Mossbauer 和 X 射线 Rietveld 研究

• 发表时间: 2005
• 期刊: Journal of Mineralogical and Petrological Science (refereed journal) 100
• 作者: Akasaka;M.;Nagashima;M.;Makino;K.;Ohashi;H
• 通讯作者: H

西南日本外帯の地殻構造:2002年四国-瀬戸内海横断地殻構造探査の成果.

日本西南部外围地区的地壳结构：2002 年四国-濑户内海地壳结构勘探的结果。

• 发表时间: 2006
• 期刊: 地震研究所彙報 80
• 作者: Tagiri;M.;Oba;T.;Fujinawa;A.;三好建正;三好建正;佐藤比呂志・児島悠司・村田明広・伊藤谷生・高須 晃他
• 通讯作者: 佐藤比呂志・児島悠司・村田明広・伊藤谷生・高須 晃他

岡山県大佐山三郡変成岩に産する含クロム珪酸塩鉱物の産状と化学組成-特に含クロムパンペリー石について-

冈山县小佐山三群变质岩中存在的含铬硅酸盐矿物的赋存状态及化学成分 - 特别是含铬泵贝利石 -

• 发表时间: 2007
• 作者: Michibayashi;K.;N.Abe et al.;浜田麻希.・阪本志津枝・赤坂正秀・高須 晃
• 通讯作者: 浜田麻希.・阪本志津枝・赤坂正秀・高須 晃