Science: Fourth Quarter - MT #1

Volcano

• Opening or vent in a planet’s crust where molten rock, ash, and gases escape from below

• Mostly located on boundaries of tectonic plates

Divergent Boundary

When tectonic plates move away from each other causing earthquakes and volcanic activity. The cooled magma produces an oceanic crust.

Convergent Boundary

When tectonic plates collide, it can create mountain ranges or trenches

Ring of Fire

Contain 75% of volcanoes

Mount Vesuvius

A stratovolcano located in Italy and erupted in 79 AD

Mount Pinatubo

An active stratovolcano in the Zambales, Philippines that erupted in 1999

Active Volcanoes

Has erupted within 10,000 years or erupted in recorded history

Mt. Asog/Iriga

Inactive volcano in Camarines Sur

Mt. Labo

Inactive volcano in Camarines Norte

Inactive Volcanoes

Has not erupted in a while but is capable of erupting 

Extinct Volcanoes

Has not erupted in recent history or has depleted magma supply

Mt. Batulao

Extinct volcano in Batangas

Composite/Stratovolcano

• The most common type of volcano; a tall crater where pyroclastic materials and lava escape

• Height is due to cooled-down volcanic materials

• Magma has a high content of silica, making the lava thick or viscous and capable of reaching great heights 

• Ex. Mayon Volcano, Albay; Mt. Krakatoa, Indonesia; Mt. Pelee, Martinique

Shield Volcano

• Flat and broad

• Has a lower percentage of silica 

• Ex. Mt Mauna Loa, Hawaii

Cinder/Pyroclastic Cones

• Made up of pyroclasts or fragments of volcanic rocks that form around volcanic craters

• Most only erupt once 

• Ex. Taal Volcano

Crust

The outermost layer of the earth, the upper layer of lithosphere

Mantle

Thicker layer under crust

Asthenosphere

Portion of mantle that contains molten rock

Geothermal Energy

Energy stored in the Earth’s crust 

Geothermal Reservoir

Where geothermal energy can be harnessed

Heat Source

Magma deep inside the earth

Water

Transport energy from the source

Cap Rock

Prevents water and steam from escaping

Hydrothermal Reservoirs

Contain hydrothermal fluids which are hot water or steam from porous rocks 

Geopressurized Resources

Involve brine, a solution of salt and water, which is trapped in a permeable layer of rock under high-pressure

Hot Dry Rock Reservoirs

Uses hot impermeable rocks underneath the Earth

Enhanced Geothermal System (EGS)

A fluid circulation system, through this, the rocks are fractured and water is turned into steam

Fumarole

Opening that emits steam and other gases

Hot Springs

Produced by water that is heated underground and pushed to the surface of the earth

Geysers

Occur in volcanic basins where porous, fissured rock containing pressurized water that is heated by nearby magma

Dry Steam Power Plants

• The first type of power plant to be built 

• Use steam taken from directly drilling underground

• Steam passes through a pipe, spins the turbine, powers up the generator, steam goes to a condenser, turns back to liquid, and is injected back underground 

Flash Steam Power Plants

• Hydrothermal fluids at a temperature of higher than 360 degrees Celsius

• The pressured water is pushed to the surface and enters a separator; the temperature drops turning it to steam, and the steam spins the turbine

• Fluids not turned into steam join the condensed water from the steam and injected back into the heat source 

Binary Power Plants

• The hydrothermal fluids never go in contact with the turbine or generator

• Uses a liquid with a lower boiling point than water (isopentane or isobutene)