Magma is molten rock, Lava is hot rock and water

Magma is black, Lava is red

Magma is found on the ocean floor, Lava is found on land surface

There is no difference between lava and magma

Many hot spots are found there.

The Pacific Ocean is very hot, causing rock to melt

The climate is hot there, causing more volcanoes

The seafloor is spreading there

Most magmas come from the asthenosphere

Some magma comes from rocks melted through decompression

Chemical compounds can decrease the melting point of rock causing magma

Some rocks are melted from magma that is on the rise

Basaltic, rhyolitic, andesitic

Rhyolitic, basaltic, andesitic

Rhyolitic, andesitic, basaltic

Andesitic, rhyolitic, basaltic

Projectiles fired from the volcano

Irritants like ash that can make the volcano erupt

Mud and lava that is extruded from the volcano

Silicate minerals in the magma

Shield volcano

Composite volcano

Volcanic Dome

Volcanic Sill

Composite volcano

Volcanic Dome

Cinder Cone

Stratovolcano

Shield volcano; made mostly from tephra.

Composite volcano, made mostly from lava flows.

Composite volcano, made mostly from a combination of lava flows and tephra.

Cinder cone volcano, made mostly from tephra.

They are associated with higher viscosity magma.

They have dormant periods between eruptions.

They produce a lot of pyroclastic materials.

They erupt gasses and ash into the atmosphere.

Gas in magma is released and pushes groundwater up through a volcano vent.

The air becomes cool at night and hot groundwater is pulled into the cool air.

Groundwater heats underground rocks, it cools, expands and pushes through openings in the ground.

Before volcanoes erupt, magma pushes groundwater out and up through openings in the ground.

Hot spots in the ocean and oceanic subduction zones

Hot spots on land and divergent boundaries

Divergent boundaries and continental subduction zones

Hot spots on land and oceanic subduction zones

Shield volcanoes

Composite Cones

Cinder Cones

Calderas

Washington, Oregon and California

Wyoming and Idaho

Hawaii

There are NO active volcanoes in the United States

In the water

In your house

On a hillside

In a valley

Carbon Monoxide

Sulfur Dioxide

Hydrogen Sulfide

Hydrogen

Volcanoes release hot air into the atmosphere, contributing to global warming.

Lava from volcanoes heats up the air in the atmosphere, contributing to global warming.

Lava cools into black rock that absorbs heat from the atmosphere, heating up the earth itself.

Ash coats the earth's surface, trapping heat and heating up the earth itself.

Yes. Global warming is a direct cause of volcanic eruptions

Yes. More people living on volcanoes causes volcanoes to erupt

Yes. More people means less groundwater and that causes volcanoes to erupt

No. People are actually keeping volcanoes from erupting