Seafloor Spreading
Seafloor spreading is a geological process occurring at mid-ocean ridges, where tectonic plates move apart and magma rises from beneath the Earth’s crust to fill the gap. As the magma cools, it forms new oceanic crust, gradually pushing older crust away from the ridge. This continuous cycle helps expand ocean basins and is a key mechanism driving plate tectonics, influencing oceanic and continental formations over millions of years.
Seafloor Spreading
Seafloor spreading is a geological process occurring at mid-ocean ridges, where tectonic plates move apart and magma rises from beneath the Earth’s crust to fill the gap. As the magma cools, it forms new oceanic crust, gradually pushing older crust away from the ridge. This continuous cycle helps expand ocean basins and is a key mechanism driving plate tectonics, influencing oceanic and continental formations over millions of years.
💡 Key Takeaways
- New oceanic crust forms at mid-ocean ridges and moves outward, widening ocean basins.
- Magnetic minerals record Earth's field reversals, creating symmetric stripes that prove seafloor spreading.
- The process is driven by mantle convection and plate tectonics, influencing subduction and continental movement.
- The age and thickness of seafloor increase with distance from ridges, helping scientists map past plate motion.
❓ Frequently Asked Questions
What is seafloor spreading?
A process at mid-ocean ridges where upwelling magma creates new oceanic crust as tectonic plates move apart.
Where does seafloor spreading occur?
Primarily at mid-ocean ridges along divergent plate boundaries where oceanic crust is formed.
What evidence supports seafloor spreading?
Rocks near ridges are younger, with age increasing away from the ridges, and magnetic stripes on the ocean floor record geomagnetic reversals symmetrically on both sides.
How does seafloor spreading relate to plate tectonics?
It explains how new crust is created and plates move; the lateral movement is balanced by crust being recycled at subduction zones.