Faults, folds and plate boundaries Flashcards
What is a fault
A fault is when there is movement of the rocks on either side or both sides of a crack.
What is a fold?
A fold is when a layer of rock bends and folds due to the pressure from the sides. Folds bent upwards are called anticlines, fold bent downwards are called synclines.
What are plate boundaries?
Plate boundaries are the edges of each tectonic plate.
What are the three types if plate boundaries?
Convergent, Divergent and Transform.
What are convergent boundaries?
Convergent boundaries occur when two plates collide together and push into each other.
What happens at a convergent boundary if one us a continental plate and the other an oceanic plate?
A subduction zone will form.
How is a subduction zone formed?
A subduction zone is where the oceanic plate moves under the continental plate. This occurs due to the oceanic plate being less dense than the continental plate and therefore gets sucked underneath when they collide.
What happens to the pressure that is built up at a subduction zone?
The built up pressure at subduction zones will often cause volcanoes to form.
What is a trench?
A trench occurs wherever there is a subduction zone.
What is a divergent boundary?
A divergent boundary occurs when two plates are moving away from each other.
What happens when two plates move away from each other?
They form mid-ocean ridges.
What happens at divergent boundaries?
New crust is being made here as molten from the mantle rises, cold and hardens to become crust.
What is at a transform boundary?
At a transform boundary. two plates slide against each other.
What do transform boundaries often cause?
Transform boundaries often cause earthquakes as the plates scrape against each other.
