Na-sanidine megacrysts from the Shavarin Caram volcano, Mongolia
Na-sanidine crystals, their fragments and corroded relicts occur in scoria of leucite trachyte from the Shavarin Caram volcano, NW Mongolia. Opalescent perfect crystals of gem quality (up to 40 mm size) of moderate Or contents (46-49) reveal the following unit cell parameters: a = 0.8334(9)nm, b = 1...
Elmentve itt :
| Szerzők: | |
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| Dokumentumtípus: | Cikk |
| Megjelent: |
University of Szeged, Department of Mineralogy, Geochemistry and Petrology
Szeged
1998
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| Sorozat: | Acta mineralogica-petrographica
39 |
| Kulcsszavak: | Kőzettan, Ásványtan, Földtan |
| Tárgyszavak: | |
| Online Access: | http://acta.bibl.u-szeged.hu/24865 |
| Tartalmi kivonat: | Na-sanidine crystals, their fragments and corroded relicts occur in scoria of leucite trachyte from the Shavarin Caram volcano, NW Mongolia. Opalescent perfect crystals of gem quality (up to 40 mm size) of moderate Or contents (46-49) reveal the following unit cell parameters: a = 0.8334(9)nm, b = 1.2997(6), c = 0.7159(6), (3 = 116.17°(5), V = 0.6949(15) nm3 . Na-sanidine together with garnet (Pyr-Alm), Al-clinopyroxene, Ti-phlogopite megacrysts represent a very strange, mostly high-pressure near-liquidus phenocryst association of high-potassic magma. Na-sanidine megacrysts, however, would crystallize probably from a Fe and fluid rich melt at lower pressure in near-solidus regions. |
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| Terjedelem/Fizikai jellemzők: | 5-12 |
| ISSN: | 0365-8066 |