Sea Floor Spreading



Sound waves used to explore ocean floor

Discovered mid-ocean ridge


mid-ocean ridge


Theory of Sea Floor Spreading

Where sea floor is spreading apart


Harry Hess

Explains continental drift (Wegener was right)

Convection currents

Magma rising up through mantle-

Splits crust apart- new seafloor





Sea floor spreading

Youngest rocks near mid-ocean ridge- get older farther away

Magnetic reversals


Pushes continents away from each other