The Mid-Atlantic Ocean Ridge is the most well-known divergent boundary. Divergent boundaries occur when two plates move away from each other. The Mid-Atlantic Ocean Ridge is expanding by an average of 2.5 centimeters per year ("Understanding plate motions [This Dynamic Earth, USGS]", 2014). This underwater mountain range is also a great example of seafloor spreading. The spreading seafloor creates new ocean lithosphere when the two plates separate and magma can spring out and fill the fissure. It also causes underwater mountains to form if magma flows upward beyond the crust (Tarbuck & Lutgens, 2015). Understanding how these chains are created is important, especially because they can give scientists an idea of ​​when new islands or continents might form. It also allows scientists to understand what can cause other plates to diverge from another.