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Earthquakes happen when pieces of land in the Earth’s crust scrape together. The crust of the Earth is made of big slabs of land called plates that are constantly moving just a little bit. The plates scrape by one another, and sometimes they don’t move smoothly. An earthquake happens when the plates get unstuck suddenly and jerkily slip past each other . The majority of earthquakes occur along plate boundaries such as the boundary between the Pacific Plate and the North American plate. One of the most active plate boundaries for earthquakes is the massive Pacific Plate commonly referred to as the Pacific Ring of Fire. The fire comes from the volcanoes that form near the edge of the plates.