Earthquake Scenarios for Puerto Rico

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Earthquakes are unsettling, destructive, and often tragic to the communities they affect. The USGS works diligently to help keep people safer by providing them and their emergency responders the science needed to respond to ongoing hazards.

Last updated February 25, 5pm Pacific time, 2020. Next update will be on March 25.

About the scenarios

Here are the three most likely scenarios for how this earthquake sequence will evolve over the next 30 days based on our aftershock forecastsThese scenarios describe three possibilities of what could happen from February 26 to March 26. Only one of these scenarios will occur within the next month. These scenarios will change over time, like our forecast.

The earthquakes in these scenarios would occur in the areas where aftershocks are happening now. Earthquakes in this sequence will continue to occur for days, months, or potentially years to come. It is very unlikely the aftershocks will cease completely within the next month.

Scenario One (Most likely):  94 percent within the next 30 days

The most likely scenario is that aftershocks will continue to decrease in frequency over the next 30 days and will be significantly lower in magnitude than the M6.4 that occurred on the 7 January 2020 (i.e., will be less than M6.0). Some of these moderately sized aftershocks (M5.0+) may cause localized damage, particularly in weak structures. Smaller magnitude earthquakes (M3.0+), when at shallow depth, may be felt by people close to the epicenters.

Scenario Two (Less likely): 6 percent within the next 30 days

A less likely scenario is an earthquake occurring of similar size as the M6.4 event. This is called a “doublet”: when two large earthquakes of similar size occur closely in time and location. This earthquake could cause additional damage in the same region and increases the number of aftershocks. 

Scenario Three (Least likely): <1 percent within the next 30 days

A much less likely scenario than the previous two scenarios is that recent earthquakes could trigger an earthquake significantly larger than the M6.4 that occurred on the 7 January (i.e., M7.0 and above). While this is a very small probability, if such an earthquake were to occur, it would have serious impacts on communities nearby. This size earthquake would also trigger its own aftershock sequence, so the rate of small and moderate earthquakes would increase again.

For More Information

Eventpage with Earthquake Details

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Date published: January 29, 2020

Magnitude 6.4 Earthquake in Puerto Rico

Links to forecasts and scenerios (below) will continue to be updated, however, text in this story will not be updated unless there is significant change to the aftershock behavior or to the USGS response to the earthquake. 

7-day aftershock forecast [English]

30-day aftershock scenarios [English | Spanish]