Since the disastrous 1939 Erzincan earthquake, there have been seven earthquakes measuring over 7.0 in magnitude, each happening at a point progressively further west. Seismologists studying this pattern believe that each earthquake may trigger the next. By analyzing the stresses along the fault caused by each large earthquake, they were able to predict the shock that hit the town of İzmit with devastating effect in August 1999. It is thought that the chain is not complete, and that an earthquake will soon strike further west along the fault – perhaps near the heavily populated city of Istanbul.