The annual release of strain energy by earthquakes in the New Madrid seismic zone, as represented by the strain factor, is calculated and cumulated. When the main annual energy release, in the form of a linear regression, is subtracted from the data, the residual curve suggests that the energy release rate is cyclical with a period of 30 to 35 yr for earthquakes of magnitude 5.5 or less. Furthermore, the current rate is well below normal and may be expected to significantly increase in the near future. Although the increase may be in the form of several small earthquakes, the historical pattern suggests that at least one earthquake of body-wave magnitude 5.0 to 5.2 may be anticipated.

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