气候变化领域集成服务门户(CCPortal): Identical metamorphic record in distinct petrochemical systems: Case study of microscopically interlayered garnet amphibolite and metapelite from the Danba dome, SW China

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DOI	10.1016/j.lithos.2023.107488
	Identical metamorphic record in distinct petrochemical systems: Case study of microscopically interlayered garnet amphibolite and metapelite from the Danba dome, SW China
	Li, Zhen M. G.; Chen, Yi-Chao; Gaidies, Fred; Zhao, Yan-Lin; Wu, Chun-Ming
发表日期	2024
ISSN	0024-4937
EISSN	1872-6143
起始页码	468
卷号	468
英文摘要	It is known that different metamorphic rocks may have different abilities in recording metamorphic processes. Here, we report microscopically interlayered garnet amphibolite and metapelite layers in a rock from the Danba dome in eastern Tibetan Plateau, SW China. Both rock types exhibit similar garnet zoning patterns, biotite and plagioclase compositions, as well as peak P-T conditions (7.3-8.0 kbar / 700-725 C-degrees for metapelite and 7.1-8.4 kbar / 690-710 C-degrees for garnet amphibolite, respectively), indicating a global thermodynamic equilibrium state and the same metamorphic record of the two distinct layers. However, medium-sized garnet exhibits homogeneous core compositions and biotite preserves lower Ti and Fe# [= Fe2+ / (Fe2+ + Mg)] at the lithological interface, possibly indicating more intense chemical homogenization at the metamorphic peak and retrograde modification at the interface caused by the possible presence of vast fluid. Sensitive high -resolution ion microprobe (SHRIMP) U-Pb dating of metamorphic zircon show a wide dispersion of ages (c. 200-155 Ma), overlapping previous age data reported for this region. These results indicate that differences in petrochemical compositions may not lead to significant distortion in the metamorphic records, including garnet zoning patterns and peak P-T conditions. This further suggests that metamorphic rocks originating from diverse protoliths, which exhibit varying peak P-T conditions within the same locality, could either be a result of the tectonic juxtaposition of distinct tectonic slices or the influence of varying fluid conditions.
英文关键词	Amphibolite; Intercalation; Metamorphic record; Metapelite; Petrochemical system
语种	英语
WOS研究方向	Geochemistry & Geophysics ; Mineralogy
WOS类目	Geochemistry & Geophysics ; Mineralogy
WOS记录号	WOS:001164978200001
来源期刊	LITHOS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/301665
作者单位	Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Carleton University
推荐引用方式 GB/T 7714	Li, Zhen M. G.,Chen, Yi-Chao,Gaidies, Fred,et al. Identical metamorphic record in distinct petrochemical systems: Case study of microscopically interlayered garnet amphibolite and metapelite from the Danba dome, SW China[J],2024,468.
APA	Li, Zhen M. G.,Chen, Yi-Chao,Gaidies, Fred,Zhao, Yan-Lin,&Wu, Chun-Ming.(2024).Identical metamorphic record in distinct petrochemical systems: Case study of microscopically interlayered garnet amphibolite and metapelite from the Danba dome, SW China.LITHOS,468.
MLA	Li, Zhen M. G.,et al."Identical metamorphic record in distinct petrochemical systems: Case study of microscopically interlayered garnet amphibolite and metapelite from the Danba dome, SW China".LITHOS 468(2024).