Essential Notes - Tectonics - Edexcel Geography A-level

A graphical representation of steps carried out in hazard recovery with a rough indication of time frame.

The Richter Scale and the Moment Magnitude Scale are used to measure earthquake magnitude.

Earthquakes can occur near the middle of plates (intraplate) due to pre-existing weaknesses in the crust that become reactivated.

Degg’s Disaster Model suggests a disaster only happens when a hazardous event meets a vulnerable population.

The Pacific Plate is an example of an oceanic plate with a lot of subduction around its edges.

It shows how quickly an area deteriorates and recovers.

It empowers communities to understand hazards and protection measures, enhancing their resilience.

Deaths have decreased while economic losses have risen due to increased global wealth.

Resilience is how well a population can recover from a disaster.

It has led to fewer people being affected by disasters.

Kashmir had 75000 deaths while Izmit had 18000 due to Kashmir's remote mountainous location with poor access to services/infrastructure, hindering capacity to cope.

The stages are Preparedness, Response, Recovery, and Mitigation.

The gap will most likely fill with water and separate completely from the main island.

The Mercalli Scale measures the intensity of an earthquake based on the damage produced.

The VEI is used to monitor volcanic eruptions by calculating the amount of energy released and the type of eruption.

The two types of tectonic plates are oceanic (thin and dense) and continental (thick).

One plate is forced under the other, getting stuck due to friction, and when they suddenly jerk past one another, energy is released as large seismic waves.

Crustal fracturing, landslides, avalanches, and liquefaction.

It involves being ready for an event to occur through public awareness, education, and training.

At constructive plate boundaries, magma rises in the gap left by separating oceanic plates, forming new land when it cools, resulting in the ocean floor spreading.

International satellites and aircraft, such as those used by GNS Science in New Zealand, utilize light detection and ranging.

Governments can modify the event or the resilience/vulnerability of affected people.

Palaeomagnetism studies the magnetic patterns of cooled magma, which helps identify the age of oceanic crust by showing the direction of the earth’s magnetic field over millions of years.

The risk equation represents the likelihood of humans being affected by a hazard, calculated as Risk = Capacity to Cope x Hazard x Vulnerability.

They are designed to withstand natural disasters, such as aseismic skyscrapers in Japan that can endure earthquakes.

Geophysical hazards occur near plate boundaries.

Slab pull occurs when a plate subducts, pulling the rest of the plate with it into the mantle.

At a conservative plate boundary, parallel plates move in different directions or at different speeds without destroying any plates.

Generally, the less developed a country, the more likely it is to face severe impacts from a tectonic hazard.

Emergency aid and insurance can help communities recover from losses.

Primary Waves cause immediate shock, Secondary Waves arrive seconds later, Love Waves cause horizontal movement, and Rayleigh Waves displace land both vertically and horizontally.

By sub-marine earthquakes at subduction zones, causing water displacement and deep trough waves.

Lahars are mudflows, and jokulhlaups are glacial floods, both secondary hazards from volcanic activity.

Natural hazards can be hydro-meteorological (caused by climatic processes) or geophysical (caused by land processes).

Ridge push is the slope created when plates move apart, where gravity acts upon it, pushing the plates further away.

Magnitude, speed of onset, duration, frequency, and spatial probability can be used to compare different hazards.

At destructive and conservative boundaries.

Plates move at different speeds, building pressure until they crack, causing fault lines and releasing energy in the form of seismic waves.

In richer countries, there are high financial losses, while poorer countries face severe shocks to community wellbeing and infrastructure.

Explosive volcanic threats, landslides, earthquakes, typhoons, tsunamis, drought, and flooding.

They accelerate coastal erosion.

At constructive and destructive plate boundaries, and at hotspots.

Lava flows, phreatic eruptions, and pyroclastic flows.

A hazard is a potential threat to human life and property.

By creating stronger sea walls or planting mangrove forests to slow down the wave speed.

Similar fossils found on continents that are now separated by oceans support the idea that they were once connected.

The depth of seismic waves along the Wadati-Benioff foci shows the subduction of denser basaltic oceanic plates into the upper mantle.

Vulnerability is how susceptible a population is to damage caused by a hazard.

Urban governments face the challenge of establishing planning measures to reduce vulnerability.

It caused airline flight disruptions, financially impacting airlines and travelers globally.

The Pressure and Release model (PAR) proposes what should be tackled if the risk of a disaster is to be reduced.

The denser oceanic plate subducts below the continental plate, creating a deep ocean trench and causing explosive volcanoes due to built-up pressure from the melting plate.

Both plates build up pressure as they are not as dense as oceanic plates, leading to the formation of fold mountains from the pile-up of continental crust.

Seawater was sprayed to cool and solidify the lava flow.

Mitigation involves strategies to lessen the effects of another hazard, such as barriers and warning signals.

Corruption in government, poor warning systems, and weak community strength.

NGOs and insurers play crucial roles in minimizing loss and enhancing community wellbeing.

Hydro-meteorological hazards and human-induced disasters like famine.

Volcanoes form where the magma rises.

Wegner’s Continental Drift Theory supports the Plate Tectonic Theory.

It indicates the scale of the disaster; lower the curve, lower the quality of life.

Relief, which includes immediate local response like medical aid and search and rescue.

Land-Use Zoning involves creating policies on where it is safest to build infrastructure to reduce population and buildings in high-risk areas.

Inequality in access to education, housing, healthcare, and reliable income contribute to vulnerability.

Tectonic hazards like earthquakes occur without warning, making prediction difficult.

A rift valley is formed when any land in the middle of the separation is forced apart.

It shows that a hazardous event in a low income country will have a longer recovery time.

The focus is on long-term responses like restoring services and reconstruction.

It lowers the impact of a disaster, even though resources may not be equally distributed.

Sea Floor Spreading occurs when two oceanic plates move away from each other, allowing magma from the mantle to rise and form new crust ridges.

Reconstruction, which aims to restore the area to the same or better quality of life and rebuild infrastructure.

Subduction is the process where oceanic plates are pushed down into the mantle at mid-ocean ridges.

Japan focuses on policies to reduce vulnerability and increase coping capacity, such as the annual 'Disaster Preparedness Day'.

The shape of the volcano; super-volcanoes are the most destructive, while composite cones are more dangerous than shield volcanoes.

The heavier plate subducts, leaving an ocean trench, and built-up pressure causes underwater volcanoes, resulting in the formation of island arcs.

Immediate actions such as evacuation, medical assistance, and rescue are taken.

A disaster is when a hazard affects human wellbeing.

A volcanic hotspot is a localized area of the lithosphere with unusually high temperature due to the upwelling of hot molten material from the core.

Rehabilitation, where services begin to be restored, temporary shelters set up, and food and water distributed.

The five types of vulnerability are Economic, Environmental, Social, Knowledge, and Physical Vulnerability.

They prepare communities for disasters, improving their ability to protect themselves.

The movement of tectonic plates is caused by convection currents produced by radioactive reactions inside the Earth's core.