Tectonics Flashcards
(23 cards)
What is the Asthenosphere?
The upper mantle layer of the Earth. It is approximately 2000km wide
What is the lithosphere?
The rigid outer part of the Earth
Define Continental Crust
Crust that forms the continents of the lithosphere
Define Continental Drift
The movement of tectonic plates due to varying weights of crust.
What are convection currents?
The circulation of magma within the mantle
Define the epicentre
The point on the surface of an earthquakes origin
What is the hazard mitigation cycle?
The four stages are preparedness, response, recovery and mitigation.
Define a hot spot
Volcanoes found away from the plate boundary due to a magma plume closer to the surface
Define a magma plume
An area of hot, upwelling mantle
What is a Lahar?
A flow of mud and debris
What is oceanic crust?
Crust that is usually thinner than continental crust that forms the sea floor
What is Park’s model?
A model describing the decline and recovery of a country over time after a natural disaster
What are primary waves?
An earthquake wave causing compressions within the body of rock
What is pyroclastic flow?
A mixture of gas and rock fragments at high temperatures and travelling at high speeds
What is the Richter scale?
Measures the intensity of an earthquake
What are secondary waves?
An earthquake causing vertical displacement within the body of rock
What are seismic waves?
The energy released during an earthquake in the form of primary and secondary waves
What is slab pull?
The force contributing to the movement of tectonic plates.
What is subduction?
When the oceanic plate is forced below the continental plate due to the oceanic plate being more dense than the continental plate
What is the Benioff zone?
A region of subduction where most destructive margin earthquakes originate
CASE STUDY-Haiti
Magnitude 7 2010 9000 dead 700k affected $13 billion donated by 2015 Corrupt government
CASE STUDY-Japan
2011 Magnitude 9 Struck 100km off shore 10 metre tsunami Earthquake drills to prepare Sea walls were already in place
CASE STUDY-Iceland
2010
Flights cancelled due to ash cloud from eruption
100k flights cancelled
Airlines lost $1.7 billion
