Keywords - tectonics Flashcards
Ash
Very small solid particles ejected from a volcano during an eruption
Aseismic building design
A design for earthquake-resistant buildings which is developed to limit the potential damage to buildings to a tolerable level
Athenosphere
The upper layer of the Earth’s mantle, where convection occurs
Benioff zone
The linear zone where a descending oceanic plate is in contact with a continental plate as it is subducted. This is a zone. Of earthquake activity created by the two plates, which creates stresses and strains which are suddenly released.
Collision plate margin
Where two plates are colliding into each other, which create fold mountains - usually continental and continental
Convergent plate margin
Where the oceanic plate is subducted under a continental plate
Composite cone volcano
Also known as a cone volcano, it has steep sides and its eruptions are explosive. It erupts low silica lava which is thick and sticky meaning it cannot run very far creating the steep sides.
Conservative plate margin
Occurs where plates slide past each other in opposite directions or in the same direction but at different speeds. Friction is eventually overcome, and the plates slip past in a sudden movement. The shockwaves created produce an earthquake
Constructive plate margin
Two plates moving away from each other
Destructive plate margin
A destructive plate margin forms when an oceanic and continental plate moves towards each other. The heavier, denser oceanic plate subducts the continental plate. The oceanic plate melts and it sinks below the continental plate due to friction in the subduction zone and the heat of the mantle
Divergent plate margin
Two plates moving away from each other
Disaster
An event, such as an earthquake, that disrupts normal conditions to a point where a place or community cannot adjust and there is significant loss of life and injuries and financial cost.
Earthquake seismic waves
The shockwaves created by the release of the tension at a focal point
Epicentre
The point on the Earth’s surface directly above the hypocentre where the seismic energy is felt the most
Focal depth
The depth at which an earthquake starts. It is divided into shallow, intermediate and deep. Shallow earthquakes have the greatest impacts
Hazard
Something that has a negative impact on people in any way
Hazard management cycle
A sequence of actions and decisions related to a place or area being prepared for or responding to the threat of a natural hazard
Hazard profile
An analysis of different types of hazard or actual hazard events based on a range of criteria. This allows a useful comparison to be made
Hot spot volcano
An intra-plate location, oceanic or continental, where magma from the mantle has broken through a weak point in the crust
Hydro-meteorological hazards
Hazards associated with flowing water or the weather. These may combine with tectonic hazards, for example lahars
Hypocentre
The point inside the crust where the pressure and seismic energy is released
Intensity
The amount of damage creates by a tectonic event or other hazard
intraplate
Tectonic activity that is found away from the plate boundaries and closer to the middle of a tectonic plate
jokulhlaups
A tectonic hazard common in Iceland, where volcanic activity underneath ice caps creates large volumes of meltwater which suddenly burst out as floodwaters under the ice, when the water pressure reaches a certain level.
