Plate Tectonics and Volcanoes

Vocabulary practice flashcards covering plate tectonics, plate boundaries, the internal structure of the Earth, volcano anatomy and life cycles, the Iceland volcanic case study, and the Volcán de Fuego eruption.

Pangaea

The single massive landmass that existed $200\text{ million}$ years ago when all the continents were joined together.

Continental Drift

The theory that tectonic plates have moved over time, supported by four pieces of proof: continental fit, matching plant fossils, matching animal fossils, and matching mountain ranges.

The Crust

The solid outer layer of the Earth broken into tectonic plates, divided into a thicker continental crust and a thinner oceanic crust.

The Mantle

The middle layer of the Earth composed of molten rock known as magma.

The Core

The innermost layer of the Earth made of nickel and iron, divided into the inner core and the outer core.

Convection Currents

A continuous circular cycle where magma in the mantle is heated by the core, becomes lighter, and rises to drag the crust, then cools slightly and sinks back through the mantle to heat up again.

Constructive Plate Boundary

A boundary where convection currents pull plates apart, allowing molten magma to surface through a rift, harden, spread the seafloor, and form ridges, volcanoes, and volcanic islands.

Destructive Plate Boundary

A boundary where convection currents push an oceanic plate and a continental plate together, causing the heavier oceanic plate to sink, melt, and trigger explosive volcanic eruptions while the continental plate buckles into fold mountains.

Subduction

The process at a destructive plate boundary where the heavier oceanic plate sinks beneath the continental plate into the mantle and melts.

Conservative Plate Boundary

A boundary where plates slide side by side in opposite directions or in the same direction at different speeds, creating pressure when stuck until they slip and generate an earthquake.

San Andreas Fault

An example of a conservative plate boundary located between the Pacific Plate and the North American Plate.

Mid-Atlantic Ridge

A mid-ocean ridge formed at a constructive plate boundary between the Eurasian Plate and the North American Plate.

Magma Chamber

An underground reservoir where molten rock is stored beneath a volcano before erupting through a vent.

Crater

The opening at the top of a volcanic vent through which magma and volcanic gases erupt.

Lava

Molten rock that has breached the Earth's surface through an eruption, which subsequently cools and hardens into solid rock.

Active Volcano

A volcano that erupts regularly, such as Mount Etna in Italy.

Dormant Volcano

A volcano that has not erupted for some time, such as Mount St Helens in the USA.

Extinct Volcano

A volcano that has not erupted in historic times, such as Slemish in County Antrim.

Pacific Ring of Fire

A zone of $450$ active volcanoes situated along the tectonic edge of the Pacific Plate.

Geothermal Energy

A renewable form of energy produced by volcanic heat in Iceland, used for heating and electricity, which improves overall air quality and health in Reykjavik.

Eyjafjallajökull

An Icelandic volcano that erupted in March $2020$, discharging an ash and gas cloud that grounded over $100,000$ flights, impacted $10\text{ million}$ people, disrupted food and medicine delivery, and caused an overall cost of $\text{E}3\text{ billion}$.

Short-Term Responses

Immediate emergency measures deployed during a volcanic eruption, including evacuating residents, supplying shelter and food, giving medical care, establishing information points, and deploying search and rescue teams.

Long-Term Responses

Ongoing, proactive hazard management strategies after an eruption, centered on educating populations about future volcanic events.

Volcán de Fuego

A volcano whose deadly eruption killed $114$ people, affected between $1.4\text{ million}$ and $1.7\text{ million}$ people, and ruined $\text{E}11\text{ million}$ worth of agricultural crops.

San Miguel Los Lotes

The village that was destroyed and buried beneath $3\text{ metres}$ of hot mud and ash over an area of $1\text{ km}$ during the eruption of Volcán de Fuego.