Question 34

New seafloor

Magma moving up through the Earth's crust at mid-ocean ridges results in the formation of new seafloor. This geological process contributes to the creation of oceanic crust as the magma cools and solidifies.

A) New seafloor

This option is correct because at mid-ocean ridges, tectonic plates diverge, allowing magma from the mantle to rise and create new oceanic crust. As the magma cools upon contact with seawater, it solidifies to form new seafloor, which is a fundamental aspect of plate tectonics.

B) A coral reef

This option is incorrect as coral reefs are typically formed in shallow, warm waters and require specific biological conditions for growth. They do not form as a direct result of magma rising through the crust, which occurs at greater depths in the ocean.

C) A trench

This choice is incorrect because oceanic trenches are formed by the subduction of one tectonic plate beneath another, not by the upwelling of magma. Mid-ocean ridges are associated with divergent boundaries, whereas trenches are associated with convergent boundaries.

D) Thrust faults

This option is also incorrect. Thrust faults are a type of fault associated with convergent boundaries where tectonic plates push against each other, leading to the formation of mountains or other geological features. They are not formed by the upwelling of magma at mid-ocean ridges.

Conclusion

The formation of new seafloor is a direct result of magma rising at mid-ocean ridges, making option A the only correct choice. All other options either misrepresent geological processes or pertain to unrelated features, reinforcing that new seafloor formation is a key result of tectonic activity at these divergent boundaries.