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Explaining the theory of plate tectonics and how it relates to the formation of undersea floor structures.

The idea of plate tectonics came from Alfred Wegener. He found matching fossils in different places around the world. This led him to the idea of all of our continents were joined together. It would be impossible for certain organisms to travel great distances across the ocean. By looking at a map, he found that each continent fits together like a great big puzzle. He called this one big continent Pangea. By looking at the images below you can see how the continents fit together quite perfectly. In the right image, you can see how certain creatures made it across the continent and why these fossils were found in certain parts of the world. Now the only problem with this theory is he had no clue as to how this would happen. He was called crazy but was determined to continue his research.

Scientists began looking at crystals on old and new rock and saw a difference in the direction they are pointing. Crystals will point in the direction of the magnetic pole. After recording the data from these crystals, the information confirmed the magnetic pole drifted from the center of the earth. Theoretically, the magnetic pole should be in the same spot if the continents were not to have moved. They rotated the continents according to Wegener's theory and the path lines up almost perfectly.

Another revolutionary evidence piece they discovered was by using sonar. Sonar was developed in World War II when the navy was trying to detect any U-boats trying to sneak by their ships. Sonar sends out a sound wave that is reflected back and the data is recorded. After WWII, scientists took over the sonar and started mapping out the bottom of the seafloor. This brought the ocean floor into a whole new perspective. They found these lines across the ocean even some of them aligning perfectly with the continents. Some of these elevations are raised and some drop deep along the continent.

The ocean floor is created by different types of plate boundaries. The main one I'll be focusing on is divergent plate boundary. Divergent plate boundaries pull away from each other creating a gap for the mantle to come out. As the mantle comes out it is cooled essentially creating a new oceanic crust. Along these ridges are new sediment being created and the existing sediment is pushed away and up creating these ridges you see along the ocean floor. Although, the older sediment will eventually be recycled in a subduction boundary, also known as a convergent boundary. So unfortunately the Earth is not getting bigger, it's just a big convection in the mantle. Convection currents occur when the hot mantle rises it pushes along the tectonic plates and then when it eventually cools it gets more dense and falls. This process repeats endlessly.

Here is an amazing video to put plate tectonics into perspective. This video shows how the plate tectonics shaped our continents to how they are today.

Here is an awesome illustration video explain how tectonic plates work. It show the differences in divergent plate boundary, convergent plate boundary, and transform plate boundary.

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