VolcanoesVolcanoes

I. Molten rockI. Molten rock

A.A. Magma Magma- beneath the Earth’s - beneath the Earth’s surfacesurface

I. Molten rockI. Molten rock

B. B. LavaLava- magma that extrudes - magma that extrudes onto the surface of the Earthonto the surface of the Earth

LavaLava

C. C. Types of LavaTypes of Lava

1.1. PahoehoePahoehoe- (pa-ho-ay-ho-ay)- (pa-ho-ay-ho-ay)freely flowing lavafreely flowing lavaforms a thin skin with wrinklesforms a thin skin with wrinkleslooks like twisted rope when solidlooks like twisted rope when solidCan walk on it if coolCan walk on it if cool

Pahoehoe Pahoehoe lavalava

C. Types of LavaC. Types of Lava2. 2. AaAa- (ah-ah) - (ah-ah) rough, jagged surfacerough, jagged surfacedangerously sharp edgesdangerously sharp edgeswalking on it very perilouswalking on it very perilous

!!

Aa lavaAa lava

D. D. Different types of ConesDifferent types of Cones

1.1. Shield Volcanoes Shield Volcanoes

a. built by a steady supply of very a. built by a steady supply of very fluid basaltic lava.fluid basaltic lava.

b. Have a broad, gently sloping b. Have a broad, gently sloping cone that resembles a shield.cone that resembles a shield.

c. E.g. Mauna Loa in Hawaii c. E.g. Mauna Loa in Hawaii

- largest volcano on earth- largest volcano on earth

Shield VolcanoShield Volcano

Shield Volcano - Mauna LoaShield Volcano - Mauna Loa

Shield volcanoShield volcano Mauna LoaMauna Loa

D. Different types of ConesD. Different types of Cones

2.Cinder Cones2.Cinder Cones

a.very steep, but not high a.very steep, but not high

b. formed from explosive b. formed from explosive eruptions from a single vent.eruptions from a single vent.

c. E.g. Sunset Crater- Arizonac. E.g. Sunset Crater- Arizona

d. E.g. Paricutin- Mexicod. E.g. Paricutin- Mexico

Cinder ConeCinder Cone

Sunset Crater- ArizonaSunset Crater- Arizona

Paricutin- MexicoParicutin- Mexico

Paricutin- MexicoParicutin- Mexico

Cinder Cone - Capulin Mtn. Cinder Cone - Capulin Mtn.

3. Composite Cone3. Composite Cone

D. Different types of ConesD. Different types of Cones

3.Composite Cone3.Composite Cone

a. a. a.k.a. Stratovolcano a.k.a. Stratovolcano

b. erupts both lava and ash b. erupts both lava and ash

c. has a steep summitc. has a steep summit

Composite ConeComposite ConeMt. RainierMt. Rainier

Composite ConeComposite Cone Mt. St. Helens Mt. St. Helens

D. Different types of ConesD. Different types of Cones

3.Composite Cone3.Composite Cone

d. d. has gently sloping sideshas gently sloping sides

e. erupts explosively e. erupts explosively

f. E.g. f. E.g. Mt. VesuviusMt. Vesuvius

Mount Pele,Mount Pele,

Mt. St HelensMt. St Helens

Mt. PinatuboMt. Pinatubo

III. CratersIII. Craters

A. formed at the A. formed at the central vent of central vent of

an erupting an erupting

volcano. volcano.

B. Increase in size B. Increase in size during eruptionsduring eruptions

III. CratersIII. Craters

III. CratersIII. Craters

C. C. CalderasCalderas

1. Remnant of a volcano that 1. Remnant of a volcano that eruptederupted

2. very large crater > 5km in 2. very large crater > 5km in diameterdiameter

CalderaCaldera

CalderaCaldera

Caldera- Santorini, ItalyCaldera- Santorini, Italy

Caldera (location unknown)Caldera (location unknown)

Caldera – Kilauea (Hawaii)Caldera – Kilauea (Hawaii)

III. CratersIII. Craters

C. C. CalderasCalderas 3. E.g. Yellowstone National3. E.g. Yellowstone National

ParkPark

a. Remnant of a volcano that a. Remnant of a volcano that erupted 600,000 yrs ago.erupted 600,000 yrs ago.

b. Hot springs, bubbling mud, b. Hot springs, bubbling mud, steaming pools, geyserssteaming pools, geysers

Yellowstone National ParkYellowstone National Park

Caldera - Yellowstone Caldera - Yellowstone National ParkNational Park

Caldera – Olympus Mons Caldera – Olympus Mons (Mars)(Mars)

III. CratersIII. Craters

C. C. CalderasCalderas 4. E.g.Bahia de Banderas4. E.g.Bahia de Banderas

a. The bay at Puerto Vallartaa. The bay at Puerto Vallarta

b. Outer edge - islands in bayb. Outer edge - islands in bay

c. Inner edge is the coastlinec. Inner edge is the coastline

d. Volcano no longer actived. Volcano no longer active

Bahia de BanderasBahia de Banderas