Volcanoes: Features, Types and Volcanology

• Volcanoes are openings in a planet's crust.

Features of a volcano

• Cone: the striking part of a volcano
• Vent: where eruption takes place
• Magma Chamber: underground pool
• Crater: basin-like depression
• Caldera: much larger than original crater
• Lava: molten materials that has been erected
• Magma: molten materials inside a volcano

Types of Volcanoes

• Cinder cones: simplest type of volcano, also known as scoria cone. Examples include Mt. Paricutin in Mexico and Mt. Taal
• Composite volcanoes: also called stratovolcanoes. Examples include Mt. Mayon & Mt. Fuji
• Shield volcano: resembles a warrior's shield. Mt. Kilauea in Hawaii is an example
• Submarine volcanoes
• Subglacial volcanoes

Summit

• Highest peak of a mountain or volcano.

PHIVOLCS (Philippine Institute of Volcanology and Seismology

• Monitors earthquakes and volcanoes.

Volcanology

• The study of volcanoes.

Seismology

• The study of earthquakes.

Volcano Activity

• Active erupting volcano: currently erupting
• Active dormant volcano: not erupting
• Inactive volcano: has not erupted for more than 10,000 years

Factors Affecting Volcanic Eruption:

• Magma's temperature
• Chemical composition
• Amount of dissolved gas

Viscosity

• Stickiness and thickness of a liquid.

Types of Eruptions

• Phreatic: hot rocks come into contact with water
• Phreatomagmatic: contact between magma and water
• Strombolian: involves fountain lava

Mt. Pinatubo

• Located in the three provinces of Zambales, Tarlac, and Pampanga
• Erupted on June 15, 1991

Volcanoes in the Philippines

• The Philippines has 24 active volcanoes.