number of downloads : ?
Title Transcription
Chemical zoning of garnets from the low-grade metamorphic rocksof the Silgara Formation, Santander Massif, Eastern CordilleraColombian Andes
Title Alternative
Chemical zoning of garnets from the low-grade metamorphic rocksof the Silgara Formation, Santander Massif, Eastern Cordillera(Colombian Andes)
File
language
jpn
Author
C., Rios
Description
The Lower Paleozoic Silgara Formation is exposed in the Pescadero-Aratoca area,southwestern Santander Massif,and consists of metapelites and interlayered metabasic rocks intruded by Triassic-Jurassic calc-alkaline granites.A sequence of metamorphic zones was developed during Caledonian low-P/T metamorphism.The regional metamorphic grade of the Silgara Formation decreases southwestward,from the sillimanite zone,through the staurolite and garnet zones,to the biotite-zone.Metamolphism has occunrred under conditions of high-temperature and low-pressure(Buchan type metamorphism),and reflects the high heat flow that exists in this part of the Santander Massif.
Garnet in the pelitic schists preserves chemical zoning,with decreasing X_<Mn>,and increasing X_<Fe> and X_<Mg> from core to rim,suggesting craystal growth during increasing temperature.X_<Ca> increases outwards and reaches a maximum at mantle,and is dependant on metamolphic pressure(maximum X_<Ca> indicates peak metamorphic pressure).
Journal Title
島根大学地球資源環境学研究報告
Volume
18
Start Page
97
End Page
107
ISSN
13439774
Published Date
1999-12-25
NCID
AA11455176
Publisher
島根大学総合理工学部地球資源環境学教室
Publisher Aalternative
Department of Geoscience, Interdisciplinary Faculty of Science and Engineering, Shimane University
NII Type
Departmental Bulletin Paper
OAI-PMH Set
Interdisciplinary Graduate School of Science and Engineering
Remark
12-14,16+ / 1993+
このエントリーをはてなブックマークに追加