BGS Rock Classification Scheme

Meta-andesite

Code MAND
Description Meta-andesite
Qualifiers No qualifiers currently exist.
Definition Meta-igneous rock with field identifiable andesite protolith. Fine-grained, av. <0.25mm normal crystalline extrusive/intrusive rock; CI <35vol%, <40wt%; quartz <20% or felspathoid <10% of QAPF, feldspar >65% plagioclase; TAS-SiO2 57-63wt%, Na2O+K2O <7wt%
Linked data http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/MAND

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.