Chapter 5 Worksheet

A lava flow with a rubbly surface.
depends primarily on chemical composition, for silica in lava tends to bond together into large mocules that cant move easily.
within the flow the largest of these may be tens of meters in diameter.
but within minutes the pressure of the lava squeezing into the pillow breaks the rind, and a new blob of lava.
lava that is so viscous has it breaks in boulder like blocks as it moves; typically, such lavas are andesitic or rhyolitic.
short and bulbous flows rarely more than 1 to 2 km long.
lava freezes while still in the vent and then pushes upward as a column.
both for a molten, moving layer of lava and for the solid layer of rock that forms when the lava freezes.
A lava flow with a surface texture of smooth, glassy, and rope like ridges.
A type of fracturing that yeilds roughly hexagonal columns of basalt; columnar joints from when a dike, sill, or lava flow cools.
volcano that has erupted within the past few centuries and will likely erupt again.
volcano that has not erupted for hundred to thousands of years but does have the potential to erupt again in the future.
volcano that was active in the past but has now shut off entirely and will not erupt in the future.
tiny solid particles or liquid droplets that remains suspended in the atmosphere for a long time.
A mixture of water and pyroclastic debris that moves downslope like wet concrete.
these can reach speeds of 50 km hour and may travel for tens of kilometers.
open holes in igneous rock formed by the preservation of bubbles in magma as the magma cools into solid rocks.
A space below ground filled with magma.
A condult in a magma chamber in the shape of a long crack through which magma rises and erupts at the surface.
A circular depression at the top of a volcanic mound.
Alarge circular depression withsteep walls and a eruption as the center of the volcano collapses into the drained magma chamber below.
are brood, gentle domes whose shape resembles a soldiers shield lying on the ground.
A large cone shaped subaerial volcano consisting of alternating layers of lava and tephra.
The character of a particular volcanic eruption geologists name styles based on typical.
with particles less than 2mm in diameter made from glass shards formed either when frothy lava explosively breaks up during an eruption.
clothes of lava rain down onto the volcano from the foundation.