1) Volcanic rock
Found on
https://www.crosswordclues.com/clue/komatiite
Komatiite t is a type of ultramafic mantle-derived volcanic rock. Komatiites have low silicon, potassium and aluminium, and high to extremely high magnesium content. Komatiite was named for its type locality along the Komati River in South Africa. True komatiites are very rare and essentially restricted to rocks of Archean age, with few Proterozoi...
Found on
http://en.wikipedia.org/wiki/Komatiite
Magnesium-rich mafic to ultramafic extrusive rock.
Found on
http://www.australian-shares.com/glossary-of-terms.php.html
(from the article `Africa`) ...and rather well-preserved volcanic rocks that show evidence of submarine extrusion (i.e., emission of rock material in molten form) and formation ... ...are ferruginous sediments that were deposited on the margins of early, iron-rich oceans. Anorthosite, which consists largely of plagioclase, forms ... ...
Found on
http://www.britannica.com/eb/a-z/k/45
An ultramafic rock with a non-cumulate texture, presumed to be extrusive.
Found on
https://www.encyclo.co.uk/local/22327
No exact match found.
