Earthquakes occur in which rock deformation zone?

Earthquakes occur in which rock deformation zone?

• A. Brittle zone
• B. Ductile zone
• C. Transition zone
• D. Shear zone

Answer: (A)

Earthquakes come from rocks breaking and slipping suddenly, releasing energy as seismic waves. This happens most readily in the brittle deformation regime, where rocks are cool and strong enough to store elastic stress until they fracture along faults. That brittle behavior lets slip occur abruptly, producing earthquakes. In the ductile zone, deeper and hotter rocks deform mainly by plastic flow rather than abrupt fracture, so they don’t generate earthquakes in the same way. Because earthquakes are tied to that brittle failure of rocks, the brittle zone is the correct place where they occur most prominently.

Earthquakes come from rocks breaking and slipping suddenly, releasing energy as seismic waves. This happens most readily in the brittle deformation regime, where rocks are cool and strong enough to store elastic stress until they fracture along faults. That brittle behavior lets slip occur abruptly, producing earthquakes. In the ductile zone, deeper and hotter rocks deform mainly by plastic flow rather than abrupt fracture, so they don’t generate earthquakes in the same way. Because earthquakes are tied to that brittle failure of rocks, the brittle zone is the correct place where they occur most prominently.