What are the causes of earthquakes, according to Islamic law and science?

Earthquakes have both religious and geological causes. The religious causes may be a punishment for sins, as Allah Almighty says: "And whatever strikes you of disaster - it is because of what your hands have earned." (Quran 42:30). It may also be a trial, a test, and a means of raising the ranks of the patient, as Allah Almighty says: "And We test you with evil and with good as a trial." (Quran 21:35). As for the geological causes, those with expertise should be asked about them.