1. Where are Volcanoes Found?
3b - Students know the principal structures that form at the three different kinds of plate boundaries.
3c - Students know the explanation for the location and properties of volcanoes that are due to hot spots and the explanation for those that are due to subduction.

2. Volcanoes are found at 3 locations:
Divergent Plate Boundaries (15%)
Convergent Plate Boundaries (80%)
Hot Spots (5%)

3. Divergent Boundaries Not very Explosive!
Rift volcanism (ocean ridges)
Mostly under the oceans
Basaltic magma – Shield Volcanoes
On land – Africa & Iceland

6. Convergent Boundaries
Subduction Zones (convergence of oceanic plates)
Andesitic magma or Rhyolitic magma – Composite Volcanoes
Forms 2 main belts:
Circum-Pacific Belt -Pacific Ring of Fire
Mediterranean Belt

8. Mediterranean Belt
Ring of Fire

11. Where is the active volcano in the photo?
Hot Spots
Unusually hot areas of Earth’s mantle
Hot plumes rise toward the crust…forming magma and volcanoes
As the lithosphere moves over a hot spot….a trail of progressively older volcanoes forms
Hawaii & Yellowstone
Where is the active volcano in the photo?

15. If hot spot is under the ocean = non-explosive basaltic magma
If hot spot is under the continents = explosive rhyolitic magma

20. What kind of volcano?
What kind of magma?
Where found?

21. Where would these be found?
What kind of volcano?
What kind of magma?
Where would these be found?