Constructive Margins Flashcards
What is a constructive margin
Where plates move apart
What happens when plates move apart in oceanic areas
They produce mid-oceanic ridges
What happens when plates move apart in continental crust
They produce rift valleys
What happens when plates move apart
The space between the diverging plates is filled with basaltic lava up swelling from below.
Why are constructive margins some of the youngest parts of the earths surface?
New crust is being continuously created
What also occurs along the ridge
Volcanic activity- forming submarine volcanoes, which sometimes rise above seal level e.g. Surtsey to the south of Iceland (Iceland was also formed this way)
Constructive margins also called
Divergent margins
As new crust forms and spreads..
Transform faults occur at right angels to the plate boundary. The parts of the spreading plates on either side of these faults may move at differing rates, leading to friction and ultimately to earthquakes.
What are the earthquakes at constructive margins like
Shallow-focus, originating near the surface