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DOI	10.1016/j.epsl.2020.116421
	Strain localization and fluid-assisted deformation in apatite and its influence on trace elements and U–Pb systematics
	Ribeiro B.V.; Lagoeiro L.; Faleiros F.M.; Hunter N.J.R.; Queiroga G.; Raveggi M.; Cawood P.A.; Finch M.; Campanha G.A.C.
发表日期	2020
ISSN	0012821X
卷号	545
英文摘要	This paper presents electron backscatter diffraction (EBSD), trace element and U–Pb data of apatite grains from a granitic mylonite from the Taxaquara Shear Zone (SE Brazil). The mylonite recrystallized under upper-greenschist facies and presents two types of apatite with distinct microstructures. Type-1 apatite appears in quartz-rich layers and does not exhibit any microstructural, crystallographic, or chemical evidence of deformation/recrystallization, and resembles the original igneous apatite. Type-2 apatite appears in mica-rich layers and exhibits core-and-mantle microstructures, and intragranular subgrain development, suggesting that they have undergone dynamic recrystallization. Recrystallized tails of type-2 apatite grains exhibit a strong c-axis crystallographic preferred orientation parallel to the X-direction (stretching lineation), and lack evidence of dislocation density. This evidence from type-2 apatite grains, combined with REE depletion, high La and a negative Ce anomaly compared to type-1 grains, suggests that type-2 apatite tails underwent recrystallization via dissolution-precipitation creep, whereas parental grains underwent crystal-plastic deformation and subgrain formation through dynamic recrystallization. Phase-equilibrium modelling and quartz CPO opening-angle thermometry are consistent with recrystallization at ∼480 – 530°C and 2.2 – 5.0 kbar. We were not able to determine precise deformation ages from type-2 apatite because fluid-assisted recrystallization appears to have substantially decreased the U/Pb ratio. We find that preferential fluid flow along high-strain, biotite-rich layers in the mylonite caused type-2 apatite to recrystallise, whereas type-1 apatite in low strain layers was unaffected and retained the characteristics of the protolith. © 2020 Elsevier B.V.
关键词	apatite recrystallization dynamic recrystallization EBSD fluid-assisted recrystallization microstructures trace elements and U–Pb system
英文关键词	Creep; Dynamic recrystallization; Flow of fluids; Mica; Microstructure; Quartz; Structural geology; Trace elements; Crystal plastic deformations; Crystallographic preferred orientations; Dislocation densities; Dissolution precipitations; Electron back scatter diffraction; Fluid assisted deformation; Strain localizations; Stretching lineations; Apatite; apatite; backscatter; deformation; granite; microstructure; mylonite; recrystallization; strain; thermometry; trace element; uranium-lead dating; Brazil
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/202856
作者单位	School of Earth, Atmosphere and Environment Science, Monash University, Clayton, Victoria 3800, Australia; Federal University of Paraná, Geology Department, 100 Francisco Heráclito dos Santos Street, Bloco VI, Curitiba, 35400000, Brazil; Department of Mineralogy and Geotectonics, University of São Paulo, Rua do Lago 562, São Paulo, 05508-900, Brazil; DEGEO/EM/UFOP, Morro do Cruzeiro, Ouro Preto, MG 35400-000, Brazil
推荐引用方式 GB/T 7714	Ribeiro B.V.,Lagoeiro L.,Faleiros F.M.,等. Strain localization and fluid-assisted deformation in apatite and its influence on trace elements and U–Pb systematics[J],2020,545.
APA	Ribeiro B.V..,Lagoeiro L..,Faleiros F.M..,Hunter N.J.R..,Queiroga G..,...&Campanha G.A.C..(2020).Strain localization and fluid-assisted deformation in apatite and its influence on trace elements and U–Pb systematics.Earth and Planetary Science Letters,545.
MLA	Ribeiro B.V.,et al."Strain localization and fluid-assisted deformation in apatite and its influence on trace elements and U–Pb systematics".Earth and Planetary Science Letters 545(2020).