generally agree that there have been 42 megaquakes along the Cascadia fault in the last 10,000 years, with the most recent in January 1700. Using historic data, scientists like Dr. Chris Goldfinger, a marine geologist and professor at Oregon State University, can forecast the probability of another great quake. The Cascadia Subduction Zone is actually made up of different clusters, according to Goldfinger. On the south end of the fault, the data shows that an earthquake with a magnitude between the high sevens and low eights occurs every 250 years. We 're 300 years into a 240 year cycle, says Goldfinger. On the other hand, the north end, with the great population centers, sees a big event closer to every 500 years. But before Oregonians panic, consider Goldfinger's assessment of the statistics. For the south end of the Cascadia, there is roughly a 35-40 % probability of having a major quake in the next 50 years. On the north end, there is only a 10-15 % probability. Even if there is still plenty of time before the next big quake, much work has to be done to make sure Oregon is ready. The most important thing is to strengthen or replace infrastructure to make sure that our lifeline systems like power and water will not be so severely damaged that they require years to repair. We also need to strengthen or replace critical facilities like hospitals, fire and police facilities