Ch 22.6 Volcanoes
Volcanoes - Most are located
near plate boundaries;
specifically SUBDUCTION
ZONES
“Ring of Fire” = Edge of Pacific
Ocean stretching from Alaska to
Japan to Indonesia, where most
of the world’s volcanoes are
located.
3 Ways Volcanoes Form
1. Subduction Zones (Convergent Plate Boundaries)
(Ring of Fire)
2. Rifting & Sea Floor Spreading (Divergent Plate
Boundaries)
(African volcanoes & Iceland’s volcanoes)
3. Hot Spots – can be in the middle of a plate
(Yellowstone, Hawaii)
– a region of active magma under a plate. This active
magma forces its way through weaknesses in the crust
to form volcanoes.
Hot Spots
The Hawaiian Islands were formed as
seamounts grew over hot spots in the
Pacific.
Hot Spot Volcanoes
 Hot spot stays in the same place while the plate moves above.