Blocks of Plutonic Aspect in a Basaltic Lava from Faial, Azores
- 1 February 1966
- journal article
- research article
- Published by Cambridge University Press (CUP) in Geological Magazine
- Vol. 103 (1) , 51-60
- https://doi.org/10.1017/s001675680005041x
Abstract
A number of coarse-grained blocks, consisting of forsteritic olivine, chrome-diopside, calcic plagioclase, and chromite in varying proportions, were found in an ankaramitic basalt on Faial. With one exception, the blocks show remarkably little alteration. There is no evidence of zoning in any of the minerals. Indications of strain are frequent. Dark scoriaceous material is often present along intercrystal boundaries and fractures. The textures and gradations in composition suggest that these blocks were formed by crystal accumulation.Keywords
This publication has 4 references indexed in Scilit:
- XII.—Petrology and Petrogenesis of some Garnetiferous PeridotitesTransactions of the Royal Society of Edinburgh, 1963
- Types of Igneous CumulatesJournal of Petrology, 1960
- Zoned olivines and their petrogenetic significanceMineralogical Magazine and Journal of the Mineralogical Society, 1939
- A dispersion method of determining plagioclases in cleavage-flakesMineralogical Magazine and Journal of the Mineralogical Society, 1923