How to use the earthquake recurrence calculator
Estimate how often earthquakes of a given magnitude occur in a region using the Gutenberg-Richter law. Enter productivity constant a, b-value, magnitude of interest in the fields above; the expected earthquakes per year, return period are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “Gutenberg Richter law”, “earthquake frequency”, “how often magnitude 6 earthquakes happen”, “calculate earthquake recurrence”, “find expected earthquakes per year”.
Formula
Variables
- a — Productivity constant a
- b — b-value
- M — Magnitude of interest
Worked example
With productivity constant a = 6, b-value = 1, magnitude of interest = 6, the calculator gives expected earthquakes per year ≈ 1 per year; return period ≈ 1 years.
Frequently asked questions
What is the earthquake recurrence calculator used for?
Estimate how often earthquakes of a given magnitude occur in a region using the Gutenberg-Richter law. It helps with questions such as “Gutenberg Richter law”, “earthquake frequency”, “how often magnitude 6 earthquakes happen”.
What is the formula for the earthquake recurrence calculation?
Expected earthquakes per year (per year) = 10^(a-b × M). Return period (years) = 1 / [Expected earthquakes per year]. Here a is productivity constant a, b is b-value, M is magnitude of interest.
What inputs do I need for the earthquake recurrence (gutenberg-richter) calculator?
You need productivity constant a, b-value, magnitude of interest. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the earthquake recurrence calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the earthquake recurrence result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.