Earthquake and Faults

So faults are breaks in the earth crust. We can identify them because of the discontinuity in the structure within the earth crust across fault. And earthquake occur on these faults. So very processes by which these faults moves to a large extent is due to earthquakes. So we have a fault plane and the earthquake is so focused on this fault plane and the earthquake starts at the particular point on the fault plane and we call that the focus of the earthquake. The rock prorogates out from that point on the rupture plane to cover the entire fault plane. The rupture is in that particular earthquake. We talked about the epicenter of the earthquake a lot. The epicenter is just the surface projection of the focus of the earthquake. So if you wanted to looking at map view where the earthquake was located, we would be able to look that into the earth. We would see the focus down some depth in the earth or the epicenter, just a point vertically above that focus at the surface of the earth. So this is the focus between the faults and the earthquakes.