Lesson 09: Anatomy of Mid-Ocean Ridges


I chose to trace the Mid-Atlantic Ridge because it was very obviously a ridge. Once I completed the elevation profile, I could clearly see it was almost like a big mountain beneath the ocean, which I thought was awesome, but also weird to try and picture. (I started imagining hiking underwater and coming to this gigantic mountain range.) The profile was very rugged, which would be due to the slow spreading at that boundary. This also means there is usually a rift valley, but I had a hard time finding that. I saw two depressions on either side of the ridge, but I wasn't sure if they were rift valleys. My hypothesis is that they are parts of a former rift valley and the ridge has fairly new crust that hasn't rifted yet.

The other thing I labeled was the age of the seafloor. It's pretty easy to see the symmetry on either side of the plate boundary. I drew a line on this picture that is approximately where the elevation profile is and used this to place labels on my original profile. You can clearly see from this that the seafloor is spreading. Overall, we can learn a lot about the Earth and how it works by researching and analyzing information such as this.

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