Question

The USGS published seismic prediction data for California in a report several years ago.? Let's examine some of the published statistics. a) The report breaks California into two regions - Northern and Southern California. It indicates that there is a 75% chance of an earthquake magnitude 27.0 in Southern California in the next 30 years. The corresponding value for Northern California is 76%. Assuming the fault lines are independent, what is the probability of magnitude 7.0 anywhere in California in the next 30 years? b) The report indicates the likelihood of earthquakes on specific faults, including San Andreas in Southern California. It states the probability of a magnitude 27.0 is 19%, 27.5 is 17.3% and 28.0 is 6.8%. Assuming there is an earthquake 27.0 on the San Andreas fault, what is the probability that it was 28.0? c) The seismic performance of a mission critical structure was simulated for various earthquakes. The probability of failure was tabulated for different magnitudes. Based on the tabulated data, what is the probability that the structure fails during the next earthquake? Magnitude Structure 30-year Magnitude likelihood Failure range likelihood 100% 98% 5.0 - 5.9 6.0 - 6.9 7.0 -7.9 > 8.0 51% 1% 10% 50% 90% 4%

Answer 1

No clarity on part c.