Page 22 - Fundamentals of Physical Volcanology
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GLOSSARY xxi
volcanic tremor Relatively long-lived and steady xenolith A fragment of rock accidentally incorpor-
seismic activity associated with the flow of ated into rising magma and brought up from the
magma through a volcanic dike or conduit. interior of the planet.
volume-limited Description of a lava flow that yield strength The stress level that must be
ceases to advance because the supply of magma exceeded before a non-Newtonian fluid will
from the vent has ceased. begin to deform and flow.
welding The development of mechanical strength
between hot pyroclasts in close contact causing
them to stick together.