WEEK 6 DRRM

Volcano

is an opening (or rupture) in the surface or crust of Earth which allows hot, molten rock, ash and gases to escape from deep below the surface

Ring of Fire

is the region where more than half of the active volcanoes of the world that are located are above sea level are located or found

How Volcanoes are Formed

• when plates collide, volcano is formed

• when plates spread apart, a volcano is formed

• volcanoes are formed in the middle of a plate

Parts of a Volcano

• Vent

• Crater

• Pipe

• Cone

Kinds of Volcanoes

• Composite/Strato Volcanoes

• Shield Volcanoes

• Cinder Cone Volcanoes

Composite/Strato Volcanoes

• are formed by alternating layers of lava and rock fragments

• erupt in an explosive way

• Mayon Volcano

Shield Volcanoes

• are among the biggest volcanoes

• are made of many layers of runny lava flows

• low-explosivity

• Mauna Loa

Cinder Cone Volcanoes

• are made of lava fragments called cinders

• low-explosivity

• Paricutin Volcano

Categories of Volcano

• Active

• Inactive

Active

if it has erupted recently or about 10,000 years ago

Inactive

• also called Dormant

• if it rarely has a record of previous eruption

VEI

Volcanic Explosivity Index

Eruptive Pulse

• an explosion with eruption plume

• may last from a few seconds to minutes

Eruptive Phase

• numerous eruptions that may alternate between plume and lava surges

• may last from a few hours to days

Eruptive Episode

is composed of several phases that may last a few days, months, or years

Beneficial and Harmful Effects of Volcanic Eruptions

• attracts tourists and visitors

• adds nutrients to the soil

• creation of new islands

• release of aerosols

• acid rain

• abandoning of land and homes