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.
Volcanoes are found at 3 locations: Divergent Plate Boundaries (15%) Convergent Plate Boundaries (80%) Hot Spots (5%)
Divergent Boundaries Not very Explosive! Rift volcanism (ocean ridges) Mostly under the oceans Basaltic magma – Shield Volcanoes On land – Africa & Iceland
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
Mediterranean Belt Ring of Fire
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?
If hot spot is under the ocean = non-explosive basaltic magma If hot spot is under the continents = explosive rhyolitic magma
What kind of volcano? What kind of magma? Where found?
Where would these be found? What kind of volcano? What kind of magma? Where would these be found?