Seafloor Spreading

Mid-Ocean Ridge

• ''Scientists found that the seams formed mountain ranges that ran along the middle of some ocean floors".
• "Mid-ocean ridges form long chains of mountains that rise up from the ocean floor".
• (p.98)

How Seafloor Spreading affects the earth

• "Seafloor spreading adds more crust to the ocean floor". "At the same time,older strips of rock move outward from either side of the ridge".
• "Along the ridge,new molten materials from inside Earth rises,erupts,cools, and hardens to form a solid strip of rock".
• (p.100)

Deep-ocean trenches&the process of subduction

• "At deep-ocean trench,the oceanic crust bends downward". "In a process taking tens of millions of years,part of the ocean floor sinks back into the mantle at deep-ocean trenches".
• "The process by which the ocean floor sinks beneath a deep-ocean trench and back into the mantle again is called subduction". (p.102)

References

• Thorton,K.,Buckley,D., Miller,Z.,Padilla,M.J.,& Wysession,M.E. (2013). Interactive Earth Science. Glenview,Illinois: Pearson Education,Inc.