Major earthquake between South America and Antarctica: What and where is the Drake Passage hit by a 7.5 magnitude tremblor

A powerful magnitude 7.5 earthquake struck the Drake Passage, a critical and turbulent body of water located between the southern tip of South America and the Antarctic Peninsula. The seismic event has raised alarms for potential tsunami threats along Chile’s coast, given the passage’s proximity to the South American landmass and its complex tectonic setting.

What and where is the Drake Passage?

The Drake Passage is an oceanic channel approximately 800 to 1,000 kilometers (about 500 to 600 miles) wide, situated between Cape Horn—the southernmost point of South America in Chile—and the South Shetland Islands near Antarctica. This passage connects the southwestern Atlantic Ocean (Scotia Sea) with the southeastern Pacific Ocean and extends into the Southern Ocean.

As the narrowest waterway circumferencing Antarctica, it forms a crucial marine gateway and is known for the Antarctic Circumpolar Current (ACC)—the strongest ocean current worldwide—which moves massive volumes of cold water uninterrupted by land.


Geographically, the Drake Passage is important for global ocean circulation, climate regulation, and marine biodiversity migration. It experiences some of the world’s roughest waters, with waves that can reach up to 25 meters (80 feet) in extreme conditions due to the funneling effect of winds and currents between the continents and Antarctica.

Details of the earthquake

The earthquake was recorded on August 21, 2025, with a magnitude of 7.5. According to seismic monitoring agencies like the United States Geological Survey (USGS), the quake's epicenter was located beneath the seabed of the Drake Passage, within a tectonically complex region where the South American Plate and Antarctic Plate interact.

This region is known for active tectonics due to the ongoing divergence between the plates that opened the Drake Passage millions of years ago. Fault lines and fracture zones beneath the seafloor of the passage make it susceptible to significant seismic activity.

Tsunami threat for Chile

Following the earthquake, tsunami precautions were issued by Chilean authorities due to the passage’s proximity to Chile’s southern coast. The magnitude 7.5 quake has the potential to trigger large undersea landslides or water displacement that could generate tsunami waves heading toward populated coastal areas.

Coastal communities along Chile’s southern Pacific shore have been advised to stay alert and take precautionary measures in accordance with official tsunami warning systems.

Drake Passage’s geological significance
The Drake Passage plays a key role in both modern oceanography and geological sciences. The opening of the passage, estimated to have occurred between 49 and 17 million years ago as Antarctica separated from South America, dramatically changed global climate and ocean circulation patterns by allowing the uninterrupted flow of the Antarctic Circumpolar Current.

The seabed bathymetry and tectonics of the passage reflect its dynamic geological history, and continuous seismic monitoring is critical to understanding its influence on regional and global environmental systems.

Q: How wide and deep is the Drake Passage?
A: The passage is about 800 to 1,000 kilometers wide and has depths reaching approximately 3,400 meters (11,000 feet) on average, with some regions as deep as 4,800 meters (15,600 feet).

Q: What makes the Drake Passage so dangerous for ships?
A: The passage is known for powerful winds and waves reaching 12 meters or more, caused by the funneling effect of currents and winds between landmasses, making it one of the most challenging ocean crossings globally.