7th Seafloor Spreading Theory

Front

What is seafloor spreading?

Back

Seafloor spreading is the process by which new oceanic crust is created at mid-ocean ridges as tectonic plates move apart.

Front

What happens when oceanic and continental plates collide?

Back

The oceanic plate sinks under the continental plate due to its higher density.

Front

What causes seafloor spreading?

Back

Seafloor spreading occurs because magma below the Earth's crust is forced up toward the surface as tectonic plates move apart.

Front

How does the age of rock at mid-ocean ridges compare to continental rock?

Back

Rock at mid-ocean ridges is younger than continental rock.

Front

How is new crust formed without increasing Earth's surface area?

Back

New crust is formed at mid-ocean ridges while old crust is recycled in subduction zones.

Front

What is the average density of continental crust?

Back

The average density of continental crust is 2.8 g/cm³.

Front

What is the average density of oceanic crust?

Back

The average density of oceanic crust is 3.2 g/cm³.

Front

What geological feature is formed at mid-ocean ridges?

Back

Mid-ocean ridges are underwater mountain ranges formed by seafloor spreading.

Front

What is a subduction zone?

Back

A subduction zone is an area where one tectonic plate sinks beneath another, often leading to recycling of crust.

Front

What role does magma play in seafloor spreading?

Back

Magma rises to the surface at mid-ocean ridges, creating new oceanic crust.