Earthquakes happen when stress accumulated in rocks is released suddenly as a fault slips. Tectonic plates move continuously, but friction can lock parts of their boundaries until the stored elastic energy exceeds the strength holding the rocks in place.
What the science says
The rupture begins at a point called the hypocenter and spreads along the fault. The point on Earth's surface directly above the hypocenter is the epicenter. As the fault moves, energy radiates through the planet as seismic waves.
How the process works
Most earthquakes occur near plate boundaries, but intraplate earthquakes can also happen on old zones of weakness. Earthquakes vary enormously in size; magnitude measures the energy released, while shaking intensity describes effects at a particular location.
What scientists measure
Ground motion depends not only on magnitude and distance but also on rupture direction, local geology and sediment. Soft sediments can amplify shaking, and underwater earthquakes that displace the seafloor can generate tsunamis.
Limits and open questions
Scientists cannot predict the exact time and place of a future earthquake. They estimate probabilities from fault behavior, historical records and geologic evidence, and they use monitoring and early-warning systems to reduce risk after rupture begins.
Why this topic matters
Understanding How Do Earthquakes Happen helps connect individual observations to the larger scientific framework. Reliable explanations separate measured evidence from speculation, make uncertainty visible, and give readers a basis for interpreting new research as it appears.
