Final answer:
The probabilities of a) a M7.5-8.0 quake, and b) a M6.0+ quake in the next 50 years in this fault zone can be calculated based on historical data on earthquake occurrences and average intervals between earthquakes.
Step-by-step explanation:
The question asks for the probabilities of a) a M7.5-8.0 quake, and b) a M6.0+ quake in the next 50 years in this fault zone.
To calculate the probabilities, we need to consider historical data on earthquake occurrences in the fault zone. If we know the average interval between earthquakes and the magnitude ranges, we can estimate the probabilities.
For example, if we know that the average interval between M7.5-8.0 quakes is 100 years and the average interval between M6.0+ quakes is 50 years, we can calculate the probabilities as follows:
a) Probability of a M7.5-8.0 quake in the next 50 years = 50 years / 100 years = 0.5 or 50%
b) Probability of a M6.0+ quake in the next 50 years = 50 years / 50 years = 1 or 100%