BGS Rock Classification Scheme
Metamafic-rock - A class within meta-igneous rock based on modal composition. In the Rock Classification Scheme, these are coarse-grained meta-igneous rocks containing 35 - 90% mafic minerals. British Geological Survey Research Report RR/99/02, section 5.2 and figs. 1, 8 and 9.
Code | MMR |
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Description | Metamafic-rock - A class within meta-igneous rock based on modal composition. In the Rock Classification Scheme, these are coarse-grained meta-igneous rocks containing 35 - 90% mafic minerals. British Geological Survey Research Report RR/99/02, section 5.2 and figs. 1, 8 and 9. |
Qualifiers | No qualifiers currently exist. |
Definition | Meta-igneous rock (grain size undefined), (protolith undefined) with <65% quartz, <65% feldspar, 35-90% mafic minerals of Q+F+mafic minerals; includes some green-stone/schist/blueschist/spillite |
Linked data | http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/MMR |
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.