The above answers are certainly correct in terms of out not being able to prevent earthquakes from taking place. In fact, our ability to even predict them still seems quite primitive. The most advanced models of earthquake warnings now discussed say they may be able to give us a few minutes warning. And while this is a good thing, it just shows how little we really understand earthquakes in general and what causes them.
One exception though is that it may be actually possible for a human-induced earthquake to occur. During the Cold War, the Soviet Union experimented with disposing high level radioactive and toxic waste deep into fault lines in the Earth. Scientists noticed a marked uptick in tremors, and theorized that they were essentially lubricating sliding tectonic plates. So we can prevent extra Earthquakes perhaps by not injecting waste into the fault lines.