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Earthquakes can be categorized into several types based on their underlying causes and characteristics.

Tectonic earthquakes: These are the most common type of earthquakes and occur due to the movement of tectonic plates in the Earth’s crust. Tectonic plates are large sections of the Earth’s lithosphere that are constantly moving. When these plates collide, pull apart, or slide past each other, stress builds up at their boundaries until it is released in the form of an earthquake.

Volcanic earthquakes: Volcanic earthquakes are directly related types of earthquakes to volcanic activity. They occur when magma moves beneath the Earth’s surface and causes the surrounding rocks to fracture. These earthquakes are typically shallow and often accompany volcanic eruptions.

Induced earthquakes: Human activities, such as mining, reservoir-induced seismicity (due to the filling of large dams), and hydraulic fracturing (fracking), can trigger earthquakes. These earthquakes are known as induced earthquakes or anthropogenic earthquakes.

Intraplate earthquakes: While most earthquakes occur along the boundaries of tectonic plates, some occur within the interior of a tectonic plate. These intraplate earthquakes are generally less frequent but can still be significant.

Subduction zone earthquakes: Subduction zones are areas where one tectonic plate is being pushed beneath another plate. When the subducting plate gets stuck and then suddenly slips, it can cause a powerful earthquake, often accompanied by a tsunami.

Strike-slip earthquakes: These earthquakes occur when tectonic plates slide past each other horizontally. The San Andreas Fault in California is a famous example of a strike-slip fault.

Normal and reverse/thrust earthquakes: These terms refer to the type of fault movement during an earthquake. In a normal earthquake, the hanging wall moves downward relative to the footwall. In a reverse/thrust earthquake, the hanging wall moves upward relative to the footwall.

Aftershocks: Aftershocks are smaller earthquakes that follow the main (or “foreshock”) earthquake. They occur as the stressed crust adjusts to the changes caused by the initial earthquake.

It’s important to note that earthquakes can vary greatly in size and impact, from minor tremors that are barely felt to catastrophic events that cause significant damage and loss of life.