Phonolite is an uncommon shallow intrusive or extrusive rock, of intermediate chemical composition between felsic and mafic, with texture ranging from...

Tephriphonolite or tephri-phonolite is a mafic to intermediate extrusive igneous rock in composition between phonotephrite and phonolite. It contains 9 to 14%...

composition between phonolite and tephritePages displaying wikidata descriptions as a fallback – A volcanic rock with a composition between phonolite and tephrite...

romanized: Ye’Åksum ḥāwelt) is a 4th-century CE, 24-metre (79 ft) tall phonolite stele, weighing 160 tonnes (160 long tons; 180 short tons), in the city...

eruptive products of Erebus are anorthoclase-porphyritic tephritic phonolite and phonolite, which are the bulk of exposed lava flow on the volcano. The oldest...

they are not unlike granites, but dark green varieties are also known. Phonolite is the fine-grained extrusive equivalent. Nepheline syenites are silica-undersaturated...

active. The volcanoes are all surmounted by rocks composed of trachyte, phonolite, pantellerite, or comendite. Their activity has been attributed either...

of diverse composition Nogal Peak Trachyte (31.4 Ma) Church Mountain Phonolite (32.7 Ma) Walker Group Three Rivers Formation, divided into members: Buck...

Porphyritic tephriphonolite to phonolite lavas of the Caldera Rim group, dated to 274,000–170,000 years ago Phonolite lava flows with aegirine phenocrysts...

at 600 km3 (140 cu mi). The final phase of eruptions are preserved as phonolite domes around Mount Cargill. Traces of the old Dunedin Volcano are best...