GEOLOGY

Detailed explanation-1: -Oceanic lithosphere forms at midocean ridges, where hot magma upwells, and then cools to form plates as the material moves away from the spreading center. As the plate cools, heat flow decreases and the seafloor deepens (Fig. 3). However, only shallow (< 1 km) measurements of lithospheric temperatures are possible.

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.

Detailed explanation-3: -Sea-floor spreading is the process by which new oceanic lithosphere forms as magma rises toward the surface and solidifies. Reversals When Earth’s magnetic poles change places, this change is called a magnetic reversal.

Detailed explanation-4: -At mid-ocean ridges (spreading centers), lithospheric plates move apart. This creates space for magma to flow upward into the newly created fractures. Over time, more and more fractures form, fill with magma, and then cool and fracture. This process generates new oceanic lithosphere (ocean crust).

Detailed explanation-5: -The process of sea-floor spreading created the lithosphere under the Atlantic Ocean. As North America and South America moved away from Europe and Africa, the resulting crack was filled by mantle material, which cooled and formed new lithosphere.