- Tytuł:
- Stability relationships of REE-bearing phosphates in an alkali-rich system (nepheline syenite from the Mariupol Massif, SE Ukraine)
- Autorzy:
-
Dumańska-Słowik, M.
Budzyń, B.
Heflik, W.
Sikorska, M. - Powiązania:
- https://bibliotekanauki.pl/articles/138608.pdf
- Data publikacji:
- 2012
- Wydawca:
- Polska Akademia Nauk. Czytelnia Czasopism PAN
- Tematy:
-
fluorowy apaty
mariupolit
monacyt
pierwiastki ziem rzadkich
ponowne wytrącanie
rozpuszczanie
Ukraina
dissolution-reprecipitation
fluorapatite
fluorbritholite
Mariupolite
monazite
rare earth elements (REE)
Ukraine - Opis:
- Primary REE-enriched fluorapatite and fluorbritholite-(Ce) in nepheline syenite from the Mariupol Massif (SE Ukraine), contain textural and chemical evidence of late- to post-magmatic metasomatic alteration. REE mobilization and replacement of the primary phases by fluid-mediated coupled dissolution-reprecipitation strongly depended on the distance between the altered minerals in the host rock. Fluorapatite and fluorbritholite-(Ce) forming individual pristine grains were partially replaced by the same phase with a new composition, resulting in the presence of patchy zoning in altered grains. the increased REE contents in altered fluorapatite rim domains are related to REE mobilization from the altered REE-depleted rim domains of the fluorbritholite-(Ce). The REEs were transported by a fluid with high F activity. The alteration of fluorapatite and fluorbritholite-(Ce) grains in contact resulted in the partial replacement of the primary phases by the same phase with a new composition, but also in the partial replacement of the fluorapatite by secondary monazite and fluorite. The REE mobilized from the fluorbritholite-(Ce) in the presence of a F-rich fluid in an alkali-rich system promoted formation of monazite as the new phosphate REE-host. The presence of secondary parisite in the altered domains of the fluorapatite and fluorbritholite-(Ce) indicates a CO2 component in the fluid during metasomatic alteration.
- Źródło:
-
Acta Geologica Polonica; 2012, 62, 2; 247-265
0001-5709 - Pojawia się w:
- Acta Geologica Polonica
- Dostawca treści:
- Biblioteka Nauki