Seismic currents in the earth's mantle.
Gravity.
Cracks in the Earth's crust are primarily caused by tectonic forces, such as plate movement, which generate stress and pressure that can lead to fracturing in the crust. Additionally, natural processes like erosion, earthquakes, and volcanic activity can also contribute to the formation of cracks in the Earth's crust.
convection currentsShear
The earths crust is moved rather than pulled by things called convection currents. This is when heated rock from the earths core rises up and reaches the crust where it cools. It then sinks down again and carries on in a circle which moves the crust
volcanic mountain
Simple- Convection in the mantle causes mantle to slowly move, and it pushes against the crust. As it does this, the tectonic plates move.
pushes and pulls are things you do when energy is applied
An earthquake is started when two plates (which lie under the Earths surface) rub together this creates movement which then sometimes pulls/pushes at the earths surface and creates giant cracks in the earths surface... and that is how an earthquake is started.
pushes
they thought the metallic plates of the earths crust rubs together and pushes the earth up
the type of stress that pulls the crust is called TENSION.
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