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a dry form of lava resembling clinkers
large, circular-shaped opening formed when the top of a volcano collapses
a steep, cone-shaped hill or small mountain made of volcanic ash, cinders, and bombs piled up around a volcano's opening.
a bowl-shaped opening at the top of a volcano
an opening, a groove, a split
a volcanically active area of Earth's surface far from a tectonic plate boundary
Tephra particles between 2mm and 64mm in diameter
magma that reaches Earth's surface
dark-colored lava rich in magnesium and iron
liquid rock material that has not reahed the earth's surface
Solidified basaltic lava flow on land that has formed with smooth, ropelike surfaces
lava that flows out of fissures on the ocean floor and cools rapidly in rounded shapes
The volcanic rock ejected during an eruption, including ash, bombs, and blocks
volcanic mountain with a broad base and gently sloping sides
A composite volcanic cone built of interlayered lava flows and pyroclastic materials
Rock fragments, classified by size, that are thrown into the air during a volcanic eruption and fall to the ground.
a hole for the escape of gas or air
rock particals more that 0.25mm but less than 5mm across that are blown into the air by a volcanic eruption
The largest tephra, formed from solid rock blasted from a fissure
large, spindle-shaped clot of lava thrown out of a volcano
volcanic ash that is less than 0.25 mm in diameter
any activity that includes the movement of magma toward or onto Earth's surface
a cone-shaped hill or mountain around this opening, built up of the material that is forced out