[[Image:Basalt.jpg|thumb|300px|Basalt lava (glowing rock) oozes over basalt lava flow]]'''Basalt''' is a hard, black [[volcanic rock]] with less than about 52 weight percent [[silica]] (<math>SiO_2</math>). Because of basalt's low silica content, it has a low viscosity (resistance to flow). Therefore, basaltic lava can flow quickly and easily move more than 20 km from a [[vent]]. The low viscosity typically allows [[volcanic gas]]es to escape without generating enormous eruption columns. Basaltic lava fountains and fissure eruptions, however, still form explosive fountains hundreds of meters tall. Common minerals in basalt include [[olivine]], [[pyroxene]], and [[plagioclase]]. Basalt is erupted at temperatures between 1100 to 1250° C. | [[Image:Basalt.jpg|thumb|300px|Basalt lava (glowing rock) oozes over basalt lava flow]]'''Basalt''' is a hard, black [[volcanic rock]] with less than about 52 weight percent [[silica]] (<math>SiO_2</math>). Because of basalt's low silica content, it has a low viscosity (resistance to flow). Therefore, basaltic lava can flow quickly and easily move more than 20 km from a [[vent]]. The low viscosity typically allows [[volcanic gas]]es to escape without generating enormous eruption columns. Basaltic lava fountains and fissure eruptions, however, still form explosive fountains hundreds of meters tall. Common minerals in basalt include [[olivine]], [[pyroxene]], and [[plagioclase]]. Basalt is erupted at temperatures between 1100 to 1250° C. |