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Melting relations of some ultra alkali volcanics
Author(s) -
Tilley C. E.,
Thompson R. N.
Publication year - 1972
Publication title -
geological journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.721
H-Index - 54
eISSN - 1099-1034
pISSN - 0072-1050
DOI - 10.1002/gj.3350080106
Subject(s) - melilite , leucite , geology , olivine , geochemistry , lava , volcano , nepheline , materials science , paleontology , metallurgy , ceramic , spinel
The melting relations of a group of ultra alkali lavas are determined. They include a range of types rich in melilite and nepheline (melilite nephelinites) from the Nyiragongo volcano of the Congo and a group rich in olivine (olivine nephelinites). The liquidi of these assemblages range from 1100°C (the melilite nephelinite of the lava lake of Nyiragongo) through the Cameroons etindite (clinopyroxene nephelinite, 1118°C to 1300°C for the olivine nephelinites. For the most part the liquidi follow a course dependent on iron‐enrichmcnt. Notable departures are examples rich in leucite.