chapter 6 vocab Flashcards
Continental drift
Continents are in constant motion on the surface of earth
Pangaea
All the continents were once part of a super continent called…
Mid ocean ridge
Mountain ranges in the middle of the ocean
Sea floor spreading
New oceanic crust forms along a mid ocean ridge and older oceanic crust moves away from the ridge
Normal polarity
A state in which magnetized objects such as compass needles will orient themselves to point north
Magnetic reversal
The magnetic field reverses direction
Reverse polarity
A state in which magnetized objects would reverse direction and orient themselves to point south
Plate tectonics
Earths surface is made of rigid slabs of rock or plates that move with respect to each other
Lithosphere
The cold and rigid outermost rock layer
Divergent plate boundary
Forms when Two plates separate
Transform plate boundary
Forms when two plates slide past eachother
Subduction
The denser plate sinks below the more buoyant plate
Convergent plate boundaries
Where two plates collide
Convection
The circulation of material caused by differences in temperature and density
Ridge push
Rising mantle material at mid ocean ridges creates the potential for plates to one away with a force