When rocks underground suddenly break apart. It causes seismic waves that make the ground shake, making an earthquake occur.
Answer:
Earthquakes occur along the margin as a result of the plates grinding together, but no major landforms are made. As the plates move apart lava erupts into the ocean cooling and forming new crust. This can also form ocean ridges where the lava that comes up cools and turns into underwater mountains. Earthquakes happen when the boundaries of the Earth's tectonic plates bump and slide past one another; sometimes, they get stuck on jagged edges and cause earthquakes once they are released. These earthquakes are always followed by aftershocks starting from the same epicenter.
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