Intensity Measure Relationship (IMR)

This is one of the two main modeling components in OpenSHA (the other being an ERF).

An IMR is any entity that can take a Site and Earthquake Rupture object, and return the probability of exceeding a given IML (or IMLs) for a specified IMT.

An IMR must be capable of providing the following information as well:

  • List of supported IMTs
  • List of Site-related Parameters (if any) the calculation depends upon

Note that at this level no presumptions are made with respect to how the probabilities are computed. This allows the flexibility of using either traditional Attenuation Relationships or full waveform modeling from first principles of physics.

The following types of IMR are currently implemented:

Click here for a graphical depiction of other potential types of IMRs.