sea-floor spreading copy the following map of the ocean floor between continents. label the parts of...

Sea-Floor Spreading

Copy the following map of the ocean floor between continents.

Label the parts of your map as we go along.

Sea-Floor Spreading

Mantle

Oceanic crust

Mid-ocean ridge

Convection currents in the asthenosphere push the crust apart.

Sea-Floor Spreading

Magma

Mantle

Oceanic crust

Mid-ocean ridge

Sea-Floor Spreading

Magma

Mantle

Oceanic crust

Sea-floor spreading

Mid-ocean ridge

Sea-floor spreading:

New magma is pushed up at the mid-ocean ridge, which pushes the older

rock away.

Sea-Floor Spreading

Magma

Mantle

Oceanic crust

Sea-floor spreading

Mid-ocean ridge

Newly formedoceanic crust

Sea-Floor Spreading

Magma

Mantle

Oceanic crust

Sea-floor spreading

Mid-ocean ridge

Newly formedoceanic crust

Old oceanic crust

Sea-Floor Spreading

Magma

Mantle

Oceanic crust

Sea-floor spreading

Mid-ocean ridge

Newly formedoceanic crust

Old oceanic crust

Tren

ch

Continentalcrust

Sea-Floor Spreading

Magma

Mantle

Oceanic crust

Sea-floor spreading

Mid-ocean ridge

Newly formedoceanic crust

Old oceanic crust

Tren

ch

Continentalcrust

Subduction: Old oceanic

crust is pushed under a continent causing the rock to melt back into

magma in the mantle.

Sea-Floor Spreading

Mid-ocean ridge

Molten material

Oceanic crust

Deep-ocean trenches

eruptsthrough

forms

subductedthroughforms

Sea-Floor Spreading

Mid-ocean ridge

Molten material

Oceanic crust

Deep-ocean trenches

eruptsthrough

forms

subductedthroughforms

Sea-Floor Spreading

Mid-ocean ridge

Molten material

Oceanic crust

Deep-ocean trenches

eruptsthrough

forms

subductedthroughforms

Sea-Floor Spreading

Mid-ocean ridge

Molten material

Oceanic crust

Deep-ocean trenches

eruptsthrough

forms

subductedthroughforms