Massachusetts vs Pennsylvania Earthquake Risk

Massachusetts has a higher earthquake risk with a score of 3/10 (Low-Moderate) compared to Pennsylvania at 2/10 (Low). This means Massachusetts faces more frequent and potentially more destructive seismic events.

Massachusetts averages approximately 5 earthquakes per year, while Pennsylvania averages about 3 per year. Massachusetts experiences roughly 2 more earthquakes annually.

Massachusetts is associated with Cape Ann seismic zone. Pennsylvania is associated with Minor intraplate zones. These fault systems determine the type and frequency of seismic activity each state experiences.

In Massachusetts, approximately 10% of the population lives in areas at risk from earthquakes, compared to 3% in Pennsylvania. Massachusetts has a larger percentage of residents exposed to seismic hazard.

Massachusetts's most notable earthquake: 1755 Cape Ann (M6.0). Pennsylvania's most notable earthquake: 1994 Reading (M4.6). These historical events illustrate the seismic potential of each state.