Summary

Two powerful earthquakes shook the Earth on October 16, 2025:

• A M6.3 quake in the Drake Passage between South America and Antarctica.

• A M6.5 quake near Papua, Indonesia.

Both quakes occurred within hours of each other and did not trigger tsunamis.
Together, they highlight the persistent seismic unrest along the Pacific Ring of Fire — a reminder of how dynamic and unpredictable our planet remains.

M6.3 Earthquake Strikes the Drake Passage

The first quake occurred at 01:42 UTC on Thursday, October 16. The Drake Passage is the rough sea channel separating South America from Antarctica. It is famous for strong winds but rarely experiences large earthquakes.

According to USGS, the quake measured magnitude 6.3 at a depth of 10 km (6.2 miles). EMSC reported a similar strength but at 20 km (12.4 miles) deep.
The epicenter was located about 686 km (426 miles) south of Tolhuin and 693 km (430 miles) southeast of Ushuaia, Argentina — the southernmost city in the world.

No tsunami warnings were issued. People at sea felt only light to moderate shaking.
USGS issued a Green Alert for potential casualties and damage, meaning that serious losses were unlikely.

Interestingly, this quake followed a M7.6 earthquake in the same region on October 10, 2025. That earlier event caused a temporary tsunami warning. The M6.3 tremor is therefore considered a strong aftershock of the major quake six days earlier.

M6.5 Earthquake Hits Papua, Indonesia

A few hours later, at 05:48 UTC, another powerful quake struck near Papua, Indonesia. This region lies along the northern edge of the Australian tectonic plate, where it meets the Pacific Plate.

The USGS reported a magnitude of 6.5 at a depth of 35 km (21.7 miles). Meanwhile, EMSC measured the quake at 11 km (6.8 miles) depth.
The epicenter was located around 200 km (125 miles) west-northwest of Jayapura and 270 km (167 miles) west-northwest of Vanimo, Papua New Guinea.

According to initial estimates, nearly 1.4 million people felt the shaking. About 23,000 experienced strong tremors and 22,000 moderate ones.
The Pacific Tsunami Warning Center (PTWC) confirmed there was no tsunami threat.

USGS also issued a Green Alert, suggesting a low probability of casualties or heavy damage.
However, shallow earthquakes in mountainous areas often lead to secondary hazards. Landslides or ground liquefaction could still occur, especially where soils are saturated or infrastructure is weak.

Why These Earthquakes Matter

Both earthquakes happened along the Pacific Ring of Fire, the world’s most active seismic zone. This region produces about 90% of all global earthquakes.

The Drake Passage lies at the boundary between the Antarctic and South American Plates. Meanwhile, Papua sits at the collision zone between the Australian and Pacific Plates.

Although neither quake caused major destruction, together they demonstrate how 2025 continues to be a year of high global seismic activity. Several M6+ and M7+ earthquakes have already occurred in October alone.