Mineral Evolution and Zircon Geochronology of Mafic Enclave in Granitic Gneiss of the Quanji Block and Implications for Paleoproterozoic Regional Metamorphism
详细信息
- 责任者：Zhang Lu (Faculty of Earth Sciences ; China University of Geosciences ; Wuhan 430074 ; China) ; Liao Fanxi
- 刊名：Earth Science Frontiers
- 出版年：2011
- 卷期：18(2)
- 关键词：镁铁质成分 ; mafic composition ; 花岗质片麻岩 ; granitic gneiss ; 铀—铅计时 ; U-Pb dating ; 青藏高原 ; Qinghai-Tibetan Plateau
- 页码：p.79-84
- 图表：5 illus., 1 table, 24 refs.
- 分类号：0802
- 出版序号：20120199
- issnNo：ISSN1005-2321
- isbnNo：CN11-3370/P
摘要
A wall-rock-derived meta-mafic enclave was discovered in the Early-Paleoproterozoic Delingha monzogranitic gneiss in the middle part of the Quanji Block. The enclave includes three rocks, from the margin to the center, being hornblende plagioclase pyroxenite, amphibolite, and garnet-hornblende schist. Three generations of mineral assemblages have been identified from petrological evidence and microtextural relationship in the hornblende plagioclase pyroxenite. It is suggested that all regionally developed monzogranitic gneisses in the Quanji Block underwent regional metamorphism with the Dakendaban Group, in response to the global assembly event of the Columbia supercontinent.