Sea floor spreading

Question 1

What provides evidence that sea floor has gradually moved apart at a mid ocean ridge

Answer 1

Palaeomagnetism (Palaeomagnetism showed the changes in magnetic polarity that sea-floor spreading results in.)

the study of ancient magnetism preserved in rocks,

Question 2

Steps of sea floor spreading

Answer 2

Seafloor spreading occurs at divergent plate boundaries.

As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense.

The less-dense material rises, often forming a mountain or elevated area of the seafloor.

Eventually, the crust cracks