felsic en · ADJ
Pronunciation
- (Southern-England) audio
Etymology
Blend of feldspar + silica, + -ic.
Meanings
-
Enriched in minerals predominantly composed of the lighter elements such as silicon, oxygen, aluminium, sodium, and potassium.
The Claret Creek Supersuite granites are a little more felsic (65-77% SiO₂), and are chemically distinctive, having higher Al₂O₃, CaO, Na₂O and Sr, and lower K₂O, Rb, Th and U than the granites of the Almaden Supersuite.
1992, David C. Champion, Bruce W. Chappell, “Petrogenesis of felsic I-type granites: an example from northern Queensland”, in P. E. Brown, B. W. Chappell, editor, The Second Hutton Symposium on the Origin of Granites and Related Rocks, Geological Society of America, Special Paper 272, page 115:Much of the southern half of the southeastern body is a mafic syenite, slightly more felsic than the shonkinite.
1954, J. C. Olson, D. R. Shawe, L. C. Pray, W. N. Sharp, Rare-Earth Mineral Deposits of the Mountain Pass District, San Bernadino County, California, U.S. Geological Survey, Professional Paper 261, page 22:Within comagmatic suites, successively younger granitoids are commonly, but not invariably, more felsic, representing progressively lower temperature mineral assemblages.
1983, Paul C. Bateman, “A summary of critical relations in the central part of Sierra Nevada batholith, California, U.S.A.”, in J. A. Roddick, editor, Circum-Pacific Plutonic Terranes, Geological Society of America, Memoir 159, page 241:
Forms
| Spelling | Features | Labels | Source |
|---|---|---|---|
| most felsic | Degree=Sup | lexicographic | |
| more felsic | Degree=Cmp | lexicographic |