Two magnitude 7.7 and 7.6 earthquakes struck Tierra del Fuego on the same day, making them the most powerful ever recorded in southern Argentina.
Key Facts
- Date
- 17 December 1949
- First shock magnitude
- 7.7 Mw
- Second shock magnitude
- 7.6 Mw
- Time between shocks
- Slightly more than 8 hours
- Max Mercalli intensity
- VIII (Severe)
- Affected settlements
- Punta Arenas and Río Gallegos
By the Numbers
Location
Cause → Event → Consequence
The epicenters of the earthquakes were located in the east of the Chilean Tierra del Fuego Province, near the Argentine border, in a seismically active zone within the island of Tierra del Fuego where tectonic stresses are concentrated.
On 17 December 1949, two major earthquakes measuring 7.7 and 7.6 on the moment magnitude scale struck the island of Tierra del Fuego slightly more than eight hours apart, registering intensities as high as VIII (Severe) on the Mercalli scale.
The earthquakes were felt across the settlements of Punta Arenas and Río Gallegos and became the most powerful seismic events ever recorded in southern Argentina, as well as among the most powerful in austral Chile, highlighting the region's significant seismic hazard.