Flashcards
Tectonics and stuff
Cards in this deck (19)
- 1Processes in plate tectonics:-Subduction
-Sea floor spreading
-Mantle convection
-Slab pull - 2What are the 4 types of boundaries?Collision
Destructive/convergent
Constructive/divergent
Conservative/transform - 3Describe destructive plate boundariesThis occurs when oceanic and continental plates move together. The oceanic plate is forced under the lighter continental plate. Friction causes melting of the oceanic plate and may trigger earthquakes
- 4Describe conservative plate boundariesOccurs 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 shock waves created produce an earthquake.
- 5Describe constructive plate boundariesOccurs when plates move apart. Volcanoes are formed as magma wells up to fill the gap, and eventually new crust is formed. An example of a constructive plate boundary is the mid-Atlantic Ridge.
- 6Describe collision plate boundariesOccurs when two plates moving together are both made from continental crust. Continental crust cannot sink or be destroyed, and as a result the land between them is pushed upwards to form high 'fold' mountains like the Himalayas.
- 7What is the hypocentreSometimes called the focus. The point within the crust where the pressure is released.
- 8Primary effects of an earthquake:Ground shaking (causes building to collapse)
Crustal fracturing (crusts splits)
Death - 9Secondary effects of an earthquake:Liquefaction (surface become less solid)
Landslides and avalanches
Tsunami
Death - 10What is a volcano?A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
- 11Primary hazards of a volcano:Lava flows
Pyroclastic flows
Tephra and ash falls
Gas eruptions - 12Secondary hazards of a volcano:Lahars
Jokulhluap - 13Case study for volcanic eruptionMontserrat - Caribbean island
18/7/95
Soufriere Hills volcano erupted
Capital- Plymouth destroyed
19 died
2/3 all houses destoryed
Unemployment rose, most left island - 14What is the VEI?Volcanic explosivity index
Describes and compares magnitude or size of eruption
Scale 0-8
Logarithmic. How long does earthquake last, height volcanic material ejected,qualitative description - 15How can you predict eruptions?Small earthquakes
Changes to the surface of the volcano
Changes to the 'tilt' of the volcano - 16What are the impacts of a tsunami?Travels inland several miles
Wash away soil
Completely change landscape
Destroy homes/businesses
Cause death - 17What is a tsunami?A series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake.
- 18Tsunami case study:2004 Indian ocean tsunami
Earthquake off east coast of Sumatra 9.2 M
17 meter high waves on impact
5m people affected,300,000 died across world,no early warming system
Epicentre was close to densely populated communities. Low lying coastlines
Overall economic cost $10b - 19—
Information
- Description
- Flashcards on Tectonics and stuff, created by Lily O'brien on 16/02/2018.
- Created by
- Lily O'brien
- Views
- 0
- Rating