December 26, 2004 M9.1 Earthquake & Indian Ocean Tsunami In the early morning hours of December 26, 2004, the Earth unleashed one of the most powerful earthquakes ever recorded. A massive M9.1 megathrust rupture off the coast of Sumatra violently displaced the seafloor, sending walls of water racing across the Indian Ocean. Within minutes, coastlines were swallowed. Entire communities vanished. Waves traveled thousands of kilometers, striking country after country with almost no warning. By the