We can start with some initial questions to ponder.

What are the compositional variations and physical properties of lavas?

How do you melt rocks to make magma that erupts as lava?

What are the sources of magma?

What are types of volcanic eruptions?

Two types of volcanic constructs and their contrasting behavior:

• shield volcanos: basaltic, low angle and very large typically, quieter eruptions, small summit calderas, example Hawaiian islands.
• strato or composite volcanos: andesitic, high angle slopes, sometimes very large calderas, potential for very devestating eruptions, example Mt. Fuji.
• what is determining these two different types of volcanic constructs?
• constructive and destructive phases of some composite volcanos.

What plate settings do different types of volcanism occur in?

• anomalous emergent portion of a spreading ridge, so basalt dominated.
• case history of Heimay eruption.
• fire + ice = jokulhaups.
• hot springs and geothermal energy.
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  Figure of a geysir in Iceland, with a jet of steam just erupting through the overlying water and initiating an eruption. This feature erupted about every 5 minutes. Note the light colored cinter around that represents silica precipitating out of the hot waters. This activity is fed by magma and hot volcanic rocks at depth.

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Volcanos on the web. Fun, extensive web resource - many others.

Next lecture outline on volcanos.