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Table T2. Explanation of nomenclature for extrusive and hypabyssal volcanic rocks.

Prefix Main name Suffix
1st: % of phenocrysts 2nd: relative abundance of phenocrysts If phyric:  
Aphyric (<1%) Sorted by increasing abundance from left to right, separated by hyphens Basalt: black to dark gray, typically olivine-bearing volcanic rock Massive lava: massive core, brecciated or vesiculated flow top and bottom, >1 m thick
Sparsely phyric (1%−5%)   Andesite: dark to light gray, contains pyroxenes and/or feldspar and/or amphibole and is typically devoid of olivine and quartz Pillow lava: subrounded bodies separated by glassy margins and/or hyaloclastite with radiating fractures 0.2 to 1 m wide
Moderately phyric (5%−20%)   Rhyolite-dacite: light gray to pale white, and/or quartz and/or biotite-bearing volcanic rock Intrusive sheet: dyke or sill, massive core with unvesiculated chilled margin, from millimeters to several meters thick
Highly phyric (>20%)     Lithic clast, pumice clast, scoria clast: volcanic or plutonic lapilli or blocks >2 cm, to be defined as sample domain
    If aphyric: Hyaloclastite: breccia made of glassy fragments
    Basalt: dark colored Breccia
    Rhyolite: light colored  

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