According to The Associated Press, the largest recorded wave reached 1.61 metres (5.3 feet) in Riung, while a wave of 0.94 metres was observed in Maurole in Ende Regency. The AP also reported that the earthquake was followed by at least 235 aftershocks, the largest measuring magnitude 6.2.

The disaster has also complicated rescue operations. Reuters reported that landslides and communication disruptions were hampering access to areas around Nagekeo and other parts of Flores. More than 150 homes were destroyed or flattened, while schools, health facilities and other public buildings were also damaged.

The latest earthquake is particularly significant because of where it occurred — and because Flores has experienced a deadly tsunami before.

Why does Indonesia get so many earthquakes?

Indonesia lies along the Pacific Ring of Fire, a horseshoe-shaped zone surrounding much of the Pacific Ocean where several tectonic plates meet.

The USGS describes the circum-Pacific Ring of Fire as the world’s most seismically and volcanically active zone. It exists largely because the Pacific Plate meets and interacts with several surrounding plates.

About 81 per cent of the world’s largest earthquakes occur along the circum-Pacific seismic belt, according to the USGS. Many are generated at subduction zones, where one tectonic plate sinks beneath another.

This helps explain why countries stretching from South America to North America and across the western Pacific repeatedly experience powerful earthquakes.

But there is an important caveat: a cluster of earthquakes does not mean the entire Ring of Fire is suddenly “waking up”. Earthquakes occur independently at different faults and plate boundaries, and a major earthquake in one part of the Ring does not automatically trigger earthquakes thousands of kilometres away.

Indonesia’s 7.7 quake and the deadly history of Flores

A major earthquake struck the Flores region in 1992, triggering a tsunami that killed about 2,500 people, according to the AP. The latest quake occurred relatively close to the location of that earlier disaster.

The 2026 earthquake also produced tsunami waves, although authorities subsequently lifted the warning.

The scale of the latest destruction is still being assessed. The AP reported that about 2,000 people had moved to temporary shelters, while more than 100 public facilities had been destroyed or damaged. Some remote communities remained difficult to reach because landslides blocked roads.

Colombia: Another major quake on the Ring of Fire

The Indonesia disaster comes days after a 7.4-magnitude earthquake struck western Colombia.

The Colombian earthquake was the country’s strongest this century. More than 250 people had been confirmed dead by Thursday, with more than 300 still missing.

The earthquake was a strike-slip event, meaning the main movement occurred horizontally along a fault rather than through the subduction mechanism responsible for many of the largest earthquakes around the Pacific.

That distinction is important. Although Colombia is part of the broader Pacific seismic belt, not every Ring of Fire earthquake is produced by the same tectonic process.

The Colombian disaster has also generated misinformation online. The Associated Press reported that conspiracy theories falsely linked the earthquake to HAARP, an atmospheric research facility in Alaska. Seismologists and the USGS rejected that claim, explaining that the earthquake was caused by natural tectonic activity.

Venezuela: Twin quakes killed thousands

In June, Venezuela was struck by two powerful earthquakes, magnitude 7.2 and 7.5, within about 30 seconds of each other, according to the USGS. The disaster caused extensive damage in northern Venezuela.

By July 17, Venezuelan authorities had reported 5,069 deaths and 16,740 injuries, according to EFE. The World Bank subsequently estimated direct physical damage at about $19.6 billion, Reuters reported.

Then, on August 10, a magnitude 7.4 earthquake struck western Colombia. Reuters reported that it was the country’s strongest earthquake this century, with hundreds killed or missing in the aftermath.

These earthquakes occurred in different tectonic settings, however. They should not be presented as one connected earthquake sequence.

Japan, Alaska and the rest of the Pacific

The Ring of Fire extends through some of the world’s most earthquake-prone countries and territories, including Japan, the Philippines, Indonesia, New Zealand, Alaska, the western United States, Mexico, Central America and the western coast of South America.

The USGS says the belt stretches along the rim of the Pacific and contains the boundaries of several tectonic plates.

That geography explains why major earthquakes can occur in countries separated by thousands of kilometres but still share a common tectonic setting.

Japan, for example, sits at a complex meeting point of several plates and has experienced some of the world’s most destructive earthquakes, including the 2011 Tohoku earthquake and tsunami.

Alaska is another major seismic zone. The USGS notes that the 1964 Alaska earthquake, at magnitude 9.2, was one of the largest earthquakes ever recorded.

Further south, the Andes run along the western edge of South America, where the Nazca Plate is being subducted beneath the South American Plate. This tectonic setting has produced some of the planet’s largest earthquakes.

Why is the Ring of Fire so active?

The answer lies in plate tectonics. Earth’s outer shell is divided into large tectonic plates that are constantly moving. Around the Pacific, several of these plates interact along boundaries where they collide, slide past each other or pull apart.

One of the most important processes is subduction. At a subduction zone, a denser oceanic plate is forced beneath another plate. Stress can accumulate along the boundary and eventually be released as a powerful earthquake.

Subduction can also generate magma, which helps explain the large number of volcanoes found around the Pacific.

The USGS describes the Ring of Fire as a zone of frequent earthquakes and volcanic eruptions associated with volcanic arcs and deep ocean trenches around the Pacific Basin.

(With inputs from National Geographic, AP, Reuters)