BGS Rock Classification Scheme

Metabasalt, plagioclase-macrophyric

Code	MBAPMA
Description	Metabasalt, plagioclase-macrophyric
Qualifiers	plagioclase-macrophyric
Definition	Meta-igneous rock, field identifiable plagioclase-macrophyric basalt protolith. Fine-grained, av. <0.25mm normal crystalline extrus/intrusive rock; CI >35 vol% >40 wt%; qtz <20% or feldspathoid <10% of QAPF, feld >65% plag. 5-20% plagioclase phenocrysts.
Linked data	http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/MBAPMA

• Return to search results

CAVEAT

"Thumbnail" definitions attached to some of the table entries are an interim attempt to provide simple short descriptions of the "unqualified" rock types presented within the BGS Rock Classification Scheme. Every effort has been made to ensure accuracy and consistency but minor contradictions or omissions might be present. The BGS welcomes any feedback pointing out such minor imperfections and/or providing constructive comment and suggestions for improvement of the definitions. In the first instance such feedback should be directed to Dr Tim McCormick.