Download Volcanoes

Earthquakes & Volcanoes
Earth’s Acne Outbreak
Assembled By
Ken Mitchell
Livermore TOPScience
What's
Down There
Volcano forms along a collision or subducting plate boundary
The long trail of the Hawaiian hotspot
Earthquakes in red, and the edges of the
major tectonic plates (outlined in yellow).
There are four types of plate boundaries:
Divergent boundaries -- where new crust is generated as the
plates pull away from each other.
Convergent boundaries -- where crust is destroyed as one
plate dives under another.
Transform boundaries -- where crust is neither produced nor
destroyed as the plates slide horizontally past each other.
Plate boundary zones -- broad belts in which boundaries are
not well defined and the effects of plate interaction are
unclear.
Example of a
Divergent
boundary
Example of an Oceanic-Continental Convergence
Oceanic-oceanic convergence
Continental-Continental Convergence
Left: The collision between the Indian and Eurasian plates has pushed
up the Himalayas and the Tibetan Plateau. At Right: Cartoon cross
sections showing the meeting of these two plates before and after their
collision. The reference points (small squares) show the amount of
uplift of an imaginary point in the Earth's crust during this mountainbuilding process.
Transform boundaries
Our good luck?
San Andreas fault
Summary of Types of Plate Boundaries
Composite
volcanoes
Various Shapes of Strato-Volcanoes
Shield Volcanoes
Cinder Cones
Spatter Cone
Eruption! Hawaii's Kilauea Volcano
Kilauea Volcano, Hawaii. August
2006 Lava Reaches the Ocean
Kilauea Volcano,
Hawaii. August 2006
Big Splash – Steam (Littoral) Explosion
Pahoehoe Lava flow, Kilauea Volcano
Pu'u O'o lava lake, Kilauea Volcano, Hawaii
Kilauea Volcano,
Aerial view of
Channelized Aa
flow
Aa and Pahoehoe Lava in Hawaii
Two Polynesian terms are used to identify the surface
character of Hawaiian lava flows. Aa, a basalt with a
rough, blocky appearance, much like furnace slag, is
shown at the left. Pahoehoe, a more fluid variety with a
smooth, satiny and sometimes glassy appearance, is
shown at the right.
Soufriere Hills,
Montserrat
Pacaya Volcano (Guatemala)
MacKenney Crater erupting July 2005
Mount St. Helens dome activity
August 2005
Arenal Volcano, Costa Rica
Mt. Mageik Volcano, Katmai National Park, Alaska
Mount St. Helens about noon, May 18, 1980
Pyroclastic flows sweep down the flanks of
Mayon Volcano, Philippines, in 1984
Lightning bolts appear above and around the Chaiten volcano