One of just ten such coral-reef systems on Earth, Mayotte lagoon was classified as a marine natural park in 2010, and the government has long hoped that it would be added to the list of UNESCO World Heritage sites.

Birth of a giant

On May 10, 2018, however, an event took place that no one could have predicted: 50 kilometers off Mayotte's east coast, an underwater volcano was born. The natural phenomena that underlay the volcano's birth and the chain of events that it has set off have forever altered the undersea landscape and the island itself, and will continue to do so for millennia.

As the volcano's growth continued, scientists recorded 800 micro-tremors that occurred several times a day over three weeks. From May 2018 to June 2019, a series of 32 earthquakes of 5 or more on the Richter scale struck the island. In its short life, the volcano has already ejected more than 5 km³ of lava, by far the most ever observed, transforming the underwater landscape.

The volcano's growth will continue for millennia, as it's part of a natural cycle of island building, destruction and rebuilding. Indeed, just 12,000 years ago, Mayotte was five times larger than it is today.