Plate Margins- Key terms Flashcards
What are submarine volcanoes?
Submarine volcanoes are where there is a split in the crust at an oceanic/oceanic constructive margin. A lower pressure zone is created where lava can erupt and form volcanoes beneath the ocean.
What are transform faults?
Transform faults are breaks that occur across oceanic ridges at right angles which lead to friction building up and being released in earthquakes
What is the Great African Rift Valley?
The Great African Rift Valley is a rift valley extending 4000km from Mozambique to the Red Sea and further north to Jordan
What is a destructive plate margin?
A destructive plate margin is where two plates move towards eachother (diverge)
What is subduction?
Subduction is the process when plates move together and the denser oceanic plate is forced under the lighter continental/oceanic plate
What is the Benioff zone?
The Benioff zone is the part of the subduction zone where heat and friction begins to melt the subducting plate into magma
What is an ocean trench?
Ocean trenches are deep trenches formed at the point in the ocean where the plate subdues e.g. the Marianas trench in the Pacific Ocean
What are fold mountains?
Fold mountains are where two continental plates move together and force eachother upwards, crumpling sediment into mountains e.g. the Himalayas
What is a collision margin?
A collision margin is a margin where two continental plates are moving together.
What are island arcs?
Island arcs are lines of volcanic islands formed by upwelling magma from the Benioff zone at a subducting plate
What is a conservative plate margin?
A conservative plate margin is when two plates slide past eachother. As they are parallel to eachother, there is no creation or destruction of the crust.
What is a fault line?
Fault lines are stresses set up by the movement of two plates moving in the same direction but not at the same speed.
What are constructive plate margins?
When two plates move apart (diverge)
