Plate Tectonics Flashcards
What is the asthenosphere?
Upper layer of the mantle, where movement happens
What is the inner core made up of?
Iron and nickel (solid)
What is ridge push?
Newly formed plates at oceanic ridges are warm (constructive plate margins), so have a higher elevation at the ridge, so gravity causes the plate to move away
What is slab pull?
At destructive plate margins, the oceanic plate subducts under gravity, pulling the plate with it
How are earthquakes distributed?
Along plate margins in narrow bands, both on land and in the sea, some in hotspots (earths crust is thin)
What are convection currents?
Heat from the core creates movement in the ductile asthenosphere, cools at the surface and sinks
Which plate movement is most likely?
Ridge push and slab pull
What is the difference between continental and oceanic crust?
Continental is thicker and less dense and older
What is the lithosphere?
The rigid and brittle part of the outer crust
