High-Mg garnets in kyanite garnet amphibolite from the Tonaru metagabbro mass in the Sambagawa metamorphic belt, Besshi district, central Shikoku, Japan
High-Mg garnets in kyanite garnet amphibolite from the Tonaru metagabbro mass in the Sambagawa metamorphic belt, Besshi district, central Shikoku, Japan
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日本四国中部别子地区三波川变质带 Tonaru 变辉长岩中的高镁石榴石
DOI：
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
M. Kabir
中科院分区：
文献类型：
--
作者：
H. Matsuura;A. Takasu;M. Kabir
Tonaru地块以大型透镜体的形式出现在Besshi地区Sambagawa片岩的最高品位部分。该岩体由透辉石角闪岩和石榴石绿帘石角闪岩组成，并伴有少量榴辉岩。Tonaru变质长岩块体西部的蓝晶石石榴石角闪岩由角闪石（钙质角闪石、镁角闪石、闪辉石）、黝帘石、蓝晶石、石榴石、云母石、paragonite、margarite、绿泥石、石英和黄铁矿组成，呈角闪石和富黝辉石层交替的带状结构。卟绿石榴石直径可达8 cm，呈递进生长带，XPrp（0.40 ~ 0.52）从岩心到边缘逐渐增大。镁元素含量在石榴石最外层边缘最高（MgO为13.82 wt%），表明石榴石边缘处于变质高峰阶段。一些微脉遍布石榴石。微脉中充满富铁石榴石，偶有黝帘石。同一石榴石微脉具有富almantine组成（XAlm 0.45-0.50, XPrp 0.250.34）。Tonaru变质长岩块体西部蓝晶石石榴石角闪岩的变质演化可能分为两个变质事件。斑岩型高镁石榴石表现出从绿帘岩-蓝片岩相到榴辉岩相变质高峰的递进变质作用。在微脉中发育的富铁石榴石通常与裂缝充填矿物（蓝晶石、黝帘石、镁角闪石、铁辉石和绿泥石）共存，是第二次高磷变质事件的证据。这第二次变质事件可能与寡长-黑云母带的进阶三巴川变质作用有关。
The Tonaru mass occurs as a large lenticular body in the highest-grade portions of the Sambagawa schists in the Besshi district. The mass consists of diopside amphibolite and garnet epidote amphibolite accompanied by small amounts of eclogite. Kyanite garnet amphibolites from the western parts of the Tonaru metagabbro mass are composed of amphibole (calcic-amphibole; magnesiohornblende, tschermakite), zoisite, kyanite, garnet, phengite, paragonite, margarite, chlorite, quartz and pyrite, and show banded structure consisting of alternating amphibole and zoisite-rich layers. Porphyroblastic garnets reach up to 8 cm in diameter, and show a prograde growth zoning, with XPrp (0.40-0.52) increasing from core to rim. Magnesium contents are highest in the outermost rim (MgO 13.82 wt%), suggests the rims of the garnets record the peak metamorphic stage. Some microveins occur throughout the garnet. These microveins are filled by Fe-rich garnet, occasionally accompanied by zoisite. Micro-veins in the same garnet have an almandine-rich (XAlm 0.45-0.50, XPrp 0.250.34) composition. The metamorphic evolution of the kyanite garnet amphibolite from the western part of the Tonaru metagabbro mass is probably divided into two metamorphic events. The porphyroblastic high-Mg garnet represents prograde metamorphism from the epidote-blueschist facies that reached into the eclogite facies at the peak metamorphism. Fe-rich garnets developed in the microveins commonly coexist with fracture-filling minerals (kyanite, zoisite, magnesiohornblende, tschermakite and chlorite) that are evidence of a second high-P metamorphic event. This second metamorphic event probably correlates with the prograde Sambagawa metamorphism of the oligoclase-biotite zone.
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影响因子：
3.1
作者：
Whitney, Donna L.;Evans, Bernard W.
通讯作者：
Evans, Bernard W.
日本四国中部别子郡三波川变质带嘎佐地块的地质和变质作用
DOI：
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发表时间：
2005
期刊：
影响因子：
--
作者：
Sakurai;T.;Takasu;A
通讯作者：
A
来自桑巴川变质带 Tonaru 绿帘石角闪岩体的顺流榴辉岩。
DOI：
--
发表时间：
2005
期刊：
The Island Arc 14(in press)
影响因子：
--
作者：
Miyagi;Y.;Takasu;A.
通讯作者：
A.
影响因子：
3.9
作者：
Aoya, M
通讯作者：
Aoya, M