Two types of scapolite in Evate carbonatite deposit (Mozambique): implications for magmatic versus metamorphic origins

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F19%3A00123844" target="_blank" >RIV/00216224:14310/19:00123844 - isvavai.cz</a>

Výsledek na webu

<a href="http://www.geopaleo.fns.uniba.sk/ageos/articles/abstract.php?path=gajdosova_et_al&vol=11&iss=2" target="_blank" >http://www.geopaleo.fns.uniba.sk/ageos/articles/abstract.php?path=gajdosova_et_al&vol=11&iss=2</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Two types of scapolite in Evate carbonatite deposit (Mozambique): implications for magmatic versus metamorphic origins

Popis výsledku v původním jazyce

Two types of scapolite occur in the Evate carbonatite deposit – the largest resource of apatite in south-east Africa. Calc-silicate rocks composed of amphiboles (hastingsite, hornblende, actinolite, and pargasite), diopside, Ba-rich phlogopite, allanite, epidote, apatite, K-feldspar, titanite, and minor calcite, also contain scapolite with 62–74 mol. % of meionite – (Me) end-member, XCl = 0.06–0.17 and the crystallochemical formula corresponding to (Ca2.46–2.99Na1.00–1.47)Σ4.00–4.20Al4.62–5.04Si6.95–7.37O24(Cl0.06–0.17S0.18–0.26C0.64–0.70)Σ1.00. In contrast, carbonatite contains scapolite ranging from Na meionite to Ca marialite with 46–63 mol. % Me, XCl = 0.19–0.47 and the crystallochemical formula (Na1.43–2.07Ca1.82–2.50)Σ3.97–4.11Al4.29–4.73Si7.27–7.70O24(Cl0.19–0.47S0.00–0.25C0.45–0.74)Σ1.00. The chemical composition of scapolites mirrors the complex history and multistage evolution of the Evate deposit. The low-Cl, high-S scapolites from calc-silicate rocks are chemically indistinguishable from metamorphic scapolites, whereas the Cl-rich scapolite from carbonatite is interpreted as magmatic in origin. The gradual Cl enrichment reflects an increasing NaCl activity in the scapolite-forming fluid or melt. Both scapolite types are closely associated with amphibole and phlogopite, thus indicating amphibolite-facies conditions during retrograde stages of Late-Proterozoic (Ediacaran) granulite-facies metamorphism and/or Ordovician reactivation.

Název v anglickém jazyce

Two types of scapolite in Evate carbonatite deposit (Mozambique): implications for magmatic versus metamorphic origins

Popis výsledku anglicky

Two types of scapolite occur in the Evate carbonatite deposit – the largest resource of apatite in south-east Africa. Calc-silicate rocks composed of amphiboles (hastingsite, hornblende, actinolite, and pargasite), diopside, Ba-rich phlogopite, allanite, epidote, apatite, K-feldspar, titanite, and minor calcite, also contain scapolite with 62–74 mol. % of meionite – (Me) end-member, XCl = 0.06–0.17 and the crystallochemical formula corresponding to (Ca2.46–2.99Na1.00–1.47)Σ4.00–4.20Al4.62–5.04Si6.95–7.37O24(Cl0.06–0.17S0.18–0.26C0.64–0.70)Σ1.00. In contrast, carbonatite contains scapolite ranging from Na meionite to Ca marialite with 46–63 mol. % Me, XCl = 0.19–0.47 and the crystallochemical formula (Na1.43–2.07Ca1.82–2.50)Σ3.97–4.11Al4.29–4.73Si7.27–7.70O24(Cl0.19–0.47S0.00–0.25C0.45–0.74)Σ1.00. The chemical composition of scapolites mirrors the complex history and multistage evolution of the Evate deposit. The low-Cl, high-S scapolites from calc-silicate rocks are chemically indistinguishable from metamorphic scapolites, whereas the Cl-rich scapolite from carbonatite is interpreted as magmatic in origin. The gradual Cl enrichment reflects an increasing NaCl activity in the scapolite-forming fluid or melt. Both scapolite types are closely associated with amphibole and phlogopite, thus indicating amphibolite-facies conditions during retrograde stages of Late-Proterozoic (Ediacaran) granulite-facies metamorphism and/or Ordovician reactivation.

Druh

J_SC - Článek v periodiku v databázi SCOPUS

CEP obor

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OECD FORD obor

10505 - Geology

Projekt

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Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2019

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Acta Geologica Slovaca

ISSN

1338-0044

e-ISSN

1338-5674

Svazek periodika

11

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

SK - Slovenská republika

Počet stran výsledku

12

Strana od-do

63-74

Kód UT WoS článku

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EID výsledku v databázi Scopus

2-s2.0-85078628902