2020
Compositional and textural variations of columbite-group minerals from beryl-columbite pegmatites in the Maršíkov District, Bohemian Massif, Czech Republic: Magmatic versus hydrothermal evolution
CHLÁDEK, Štěpán; Pavel UHER a Milan NOVÁKZákladní údaje
Originální název
Compositional and textural variations of columbite-group minerals from beryl-columbite pegmatites in the Maršíkov District, Bohemian Massif, Czech Republic: Magmatic versus hydrothermal evolution
Autoři
CHLÁDEK, Štěpán (garant); Pavel UHER a Milan NOVÁK (203 Česká republika, domácí)
Vydání
Canadian Mineralogist, Mineralogical Association of Canada, 2020, 0008-4476
Další údaje
Jazyk
angličtina
Typ výsledku
Článek v odborném periodiku
Obor
10504 Mineralogy
Stát vydavatele
Kanada
Utajení
není předmětem státního či obchodního tajemství
Odkazy
Impakt faktor
Impact factor: 1.165
Kód RIV
RIV/00216224:14310/20:00118967
Organizační jednotka
Přírodovědecká fakulta
UT WoS
000637945400007
EID Scopus
2-s2.0-85099051595
Klíčová slova anglicky
columbite-tantalite; compositional trends; granitic pegmatites
Štítky
Příznaky
Mezinárodní význam, Recenzováno
Změněno: 13. 5. 2021 18:51, Mgr. Marie Novosadová Šípková, DiS.
Anotace
V originále
We studied compositional variations in columbite group minerals (CGM) from several granitic pegmatites of the beryl-columbite subtype in the Maršíkov district, Silesian Domain of the Bohemian Massif, Czech Republic. The CGM are characterized by distinct zoned patterns in BSE images. Primary magmatic homogeneous to oscillatory zoning is preserved in corroded crystal cores, whereas the majority of the crystal volume is replaced by secondary complexly zoned domains formed via post-magmatic processes. The primary domains show relatively uniform evolutionary trends from core to rim, generally with steeply increasing Ta/(Ta + Nb) and negligible to slightly increasing Mn/(Mn + Fe). In contrast, the compositions of secondary CGM domains indicate a reversed evolution, with: (1) steeply decreasing Ta/(Ta + Nb) and relatively constant Mn/(Mn + Fe) characteristics for CGM in the Bienergraben and Scheibengraben pegmatites, and (2) insignificantly decreasing Ta/(Ta + Nb) and strongly decreasing Mn/(Mn + Fe) characteristics for CGM in the Schinderhübel I and Lysá Hora pegmatites. Patchy zoning and secondary evolution in CGM result from metasomatic replacement processes related to fluids. These fluids are probably late-magmatic and exsolved from the residual melt and in later stages locally mixed with external Mg-enriched fluids derived from the host rocks. The presence of volatiles (mainly H2O, F) facilitated high mobility of the elements and replacement of the early CGM. Textural characteristics and compositional variations in CGM show the complex evolution of the pegmatite system from the magmatic stage to subsolidus-hydrothermal conditions.
Návaznosti
GA19-05198S, projekt VaV |
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