Earth the time it takes for new rock

Earth is constantly changing. It’s the only planet that has natural events such as volcanoes and earthquakes. There’s a reason behind why the Earth’s continents are separated and it’s because of Plate tectonics. Plate tectonics is the theory in which the Earth is covered in several plates. Proof of this theory is the shape of the continents, the location of fossils, and location where most earthquakes and volcanoes occur.
If you rearrange all the continents together the location of rock types and fossils all match up. People started seeing how continents would be able to fit together after looking at the map. If you take a closer look at where most earthquakes occur, you’ll notice that most of them occur around the plate boundaries.
Subduction zones also mark the boundaries of the tectonic plates. A subduction zone is the biggest crash scene on Earth. The processes of subduction and sea-floor spreading can change the size and shape of the oceans. Because of these processes, the ocean floor is renewed about every 200 million years. That is the time it takes for new rock to form at the mid-ocean ridge, move across the ocean, and sink into a trench.
Proof of sea-floor spreading came from rock samples obtained by drilling into the ocean floor. The Glomar Challenger, a drilling ship built in 1968, gathered the samples. The Glomar Challenger sent drilling pipes through water six kilometers deep to drill holes in the ocean floor. The farther away from a ridge the samples were taken, the older the rocks were. The youngest rocks were always in the center of the ridges. This showed that sea-floor spreading really has taken place.
Earth behaves like a giant magnet, with a north pole and a south pole. Surprisingly, Earth’s magnetic poles have reversed themselves many times during Earth’s history. The last reversal happened 780,000 years ago. In conclusion, there is enough proof to support the theory of plate tectonics and the locations where most earthquakes and volcanic eruptions occur can’t be a coincidence.