Magnitude Frequency Distribution (MFD)

A Magnitude Frequency Distribution is a function that describes the rate (per year) of earthquakes across all magnitudes.

An MFD can have an analytical form or, as in the case of OpenSHA implementations, be described by rates of earthquakes over descrete intervals. In addition to an arbitrary distribution, the following types of distributions are currently supported in OpenSHA:

  • Single-Mag Distribution
  • Gutenberg-Richter Distribution
  • Tapered Gutenberg-Richter Distribution
  • Gaussian Distribution
  • Youngs and Coppersmith Distribution (AKA the"Characteristic" Distribution)
  • Summed Magnitude Frequency Distribution (the sum of other distributions)

One can learn more about these using the Magnitude-Frequency Distribution Plotter.