BGS Rock Classification Scheme

Potassic-trachybasalt - A potassic trachybasalt. British Geological Survey Research Report RR/99/06, section 5.2 and figs. 17b, 20.

Code KTRBA
Description Potassic-trachybasalt - A potassic trachybasalt. British Geological Survey Research Report RR/99/06, section 5.2 and figs. 17b, 20.
Qualifiers No qualifiers currently exist.
Definition Fine-grained, av. <0.25mm normal crystalline extrusive/intrusive rock; TAS SiO2 45-52wt%, Na2O+K2O 5-7.3wt%, (Na2O-2.0)<K2O
Linked data http://data.bgs.ac.uk/id/EarthMaterialClass/RockName/KTRBA

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.