Question

What does the presence of new rock near an oceanic ridge indicate?

There is always a deep-sea trench underneath.
There is evidence of seafloor spreading.
They are made from oceanic crust.
They have iron oriented in different directions.

Answer 1

The presence of new rock near an oceanic ridge indicates that there is evidence of seafloor spreading. Oceanic ridges are sites where tectonic plates are moving apart, allowing magma from the mantle to rise and create new oceanic crust. This process continuously produces new rock at the ridge, which is evidence of the dynamic nature of the Earth's lithosphere and the ongoing activity of seafloor spreading.