Which region in the United States is recognized for the greatest earthquake hazard?

• A. California
• B. Hawaii
• C. Florida
• D. Alaska

Answer: (D)

The main idea is that the highest earthquake hazard occurs where large, active plate-boundaries are present, especially at subduction zones that can generate megathrust earthquakes and tsunamis. Alaska sits at a major boundary where the Pacific Plate is subducting beneath the North American Plate along the Aleutian trench. This setting builds up substantial crustal strain that is released in powerful quakes, including the historical magnitude 9.2 event in 1964 that also spawned tsunamis affecting distant shores. The combination of frequent, very large earthquakes and the potential for tsunami effects makes Alaska the most hazardous region in the United States for earthquakes. California is also seismically active due to the San Andreas system, but its hazard rate and magnitudes are, on average, not as extreme as Alaska’s. Florida is seismically quiet, and Hawaii’s earthquakes are largely tied to volcanic processes rather than large subduction megathrust events, giving it a different hazard profile.