GEOLOGY

Detailed explanation-1: -The hypothesis of seafloor spreading proposed that magma rises to the surface at mid-ocean ridges, creating new seafloor. As the seafloor rocks spread away from the mid-ocean ridge, they become cooler and more dense, finally sinking or subducting into the earth’s interior. Evidence supported seafloor spreading.

Detailed explanation-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.

Detailed explanation-3: -seafloor spreading, theory that oceanic crust forms along submarine mountain zones, known collectively as the mid-ocean ridge system, and spreads out laterally away from them.

Detailed explanation-4: -Hess envisaged that oceans grew from their centres, with molten material (basalt) oozing up from the Earth’s mantle along the mid ocean ridges. This created new seafloor which then spread away from the ridge in both directions.