Seafloor Spreading Flashcard

Front

What is seafloor spreading?

Back

Seafloor spreading is the process by which new oceanic crust is formed at mid-ocean ridges and gradually moves away from the ridge, causing the ocean floor to expand.

Front

What are oceanic trenches?

Back

Oceanic trenches are deep, narrow depressions in the ocean floor formed by the subduction of one tectonic plate beneath another.

Front

What is subduction?

Back

Subduction is the geological process where one tectonic plate moves under another and sinks into the mantle, often forming oceanic trenches.

Front

What are mid-ocean ridges?

Back

Mid-ocean ridges are underwater mountain ranges formed by the upwelling of magma at divergent tectonic plate boundaries.

Front

What is the significance of magnetic patterns on the ocean floor?

Back

Magnetic patterns on the ocean floor provide evidence for seafloor spreading, showing alternating bands of normal and reversed magnetic polarity.

Front

How old is the oldest ocean crust?

Back

The oldest ocean crust is about 180-200 million years old.

Front

What is the relationship between mid-ocean ridges and new crust formation?

Back

Mid-ocean ridges are where new oceanic crust is created as magma rises to the surface, solidifying as it cools.

Front

What happens to old oceanic crust?

Back

Old oceanic crust is recycled back into the mantle at subduction zones, balancing the creation of new crust at mid-ocean ridges.

Front

What is a transform boundary?

Back

A transform boundary is a type of tectonic plate boundary where two plates slide past each other horizontally, causing earthquakes.

Front

What is the role of tectonic plates in seafloor spreading?

Back

Tectonic plates are large sections of the Earth's lithosphere that move and interact at their boundaries, driving the process of seafloor spreading.