When the Great Alaska Earthquake convulsed the south-central region of that vast state on March 27, 1964, the energy released by the upheaval -- the largest quake in recorded North American history -- was, LIFE magazine reported, "400 times the total [energy] of all nuclear bombs ever exploded" until that time. The megathrust event unleashed a colossal 200,000 megatons of energy, destroying buildings and infrastructure in Anchorage and far beyond; raising the land as much as 30 feet in some places; and sparking a major underwater landslide in Prince William Sound, which killed scores of people when the resulting waves slammed into Port Valdez.
When all was said and done, the 9.2-magnitude quake -- which struck around 5:30 in the evening on Good Friday -- and its many powerful aftershocks caused hundreds of millions of dollars in damage; killed more than 130 people (including more than a dozen tsunami-related deaths in Oregon and California) and; in ways literal and figurative, forever altered the Alaskan landscape in places like Anchorage, Seward and Valdez.
Here, on the 50th anniversary of the epic natural disaster, LIFE.com presents photos -- many of them never published in LIFE -- from the cataclysm's aftermath.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter at @LizabethRonk.