7th Grade Ch. 3 Sec. 3 Volcanic EruptionsPresentation Transcript
Ch. 3 Sec. 3 Volcanic eruptions
Thin strands of volcanic glass drawn out from molten lava have long been called Pele's hair, named for Pele, the Hawaiian goddess of volcanoes.
A single strand, with a diameter of less than 0.5 mm, may be as long as 2 m.
The strands are formed by the stretching or blowing-out of molten basaltic glass from lava, usually from lava fountains, lava cascades, and vigorous lava flows (for example, as pahoehoe lava plunges over a small cliff and at the front of an aa flow).
magma chamber vent pipe Erupting volcano labeling activity
Side vent side vent
As magma rises to surface pressure of surrounding rock on magma decreases
Dissolved gases expand forming bubbles
Cause enormous force causing eruption
hurls out ash, gases, cinders, & bombs
This car is covered with volcanic dust spewed from Mt. Pinatubo, in the Phillippines.
landslides & avalanches
hard to breathe
forms when lava cools very quickly
smooth, glossy surface
crust - Earth's outermost, rocky layer.
lava - molten rock; it usually comes out of erupting volcanoes.
magma chamber - contains magma (molten rock) deep within the Earth's crust.
side vent - vent in the side of a volcano.
vent - opening in the Earth's surface through which volcanic materials erupt.
pipe side vent magma chamber magma chamber pocket beneath the surface in which magma collects pipe long tube in ground that connects magma chamber to Earth’s surface vent opening thru. which gas & lava leave volcano vent crater crater bowl-shaped area that forms at top of volcano around central vent