Although conversions between empirically derived " sensitive " seismic parameters such as earthquake magnitude scales is mathematically cautioned as well as physically limited, some seismologists such as Brumbaugh have nevertheless attempted to produce a relationship linking ML to Md for a rather small sample of 17 events in Arizona:
32.
In October 2009, a team composed of University of Illinois and Virginia Tech researchers headed by Amr S . Elnashai, funded by the Federal Emergency Management Agency ( FEMA ), considered a scenario where all three segments of the New Madrid fault ruptured simultaneously with a total earthquake magnitude of 7.7.
33.
This was thought to be because of smaller estimated earthquake magnitude, smaller estimated fault plane, shorter estimated fault length, not having considered the shape of the fault, etc . There were also cases where large differences between estimated intensities by the Earthquake Early Warning system and the actual intensities occurred in the aftershocks and triggered earthquakes.
