When one hears the name Bermuda, the mind usually goes to the famous Bermuda Triangle and stories of missing ships and airplanes. In those cases, science has largely provided answers, attributing most incidents to extreme weather events and human error.

This time, however, scientists are focusing not on what happens above Bermuda, but on what lies deep below it. A team of researchers has identified a geological “anomaly” beneath the North Atlantic island group that has not been observed anywhere else on the planet.

According to the study, beneath the oceanic crust in the Bermuda region there is a layer of rock about 20 kilometers (12.4 miles) thick. This feature stands out because normally, beneath the oceanic crust, the Earth’s mantle is found directly below.

Geologist William Fraser from Carnegie Science in Washington, speaking to Live Science, explained why the finding is considered unique. He said, “Normally you would expect to encounter the mantle directly below the oceanic crust. In the case of Bermuda, however, there is an additional layer placed beneath the crust, within the tectonic plate on which the island sits.”

The origin of this unusually thick rock layer remains unknown. Scientists estimate, however, that it may be linked to the way the Bermuda islands themselves were formed and how they managed to rise above the sea surface.

The archipelago sits atop an oceanic rise, but the volcanic activity that could have created it remains mysterious. The last known volcanic eruption in the area occurred about 31 million years ago. One hypothesis being considered is that this eruption significantly uplifted the seafloor, and that the geological anomaly discovered today is a remnant of that process.

As Fraser notes, studying such “extreme” geological cases has broader significance. “By understanding a unique place like Bermuda, we can better understand regions that do not have such pronounced peculiarities. It helps us distinguish which processes on Earth are the most common and which are truly extreme,” he said.

Researchers emphasize that the ocean depths still hold major secrets. Recently, another scientific team revealed the existence of a “lost” continent, Zealandia (Te Riu-a-Māui), over a billion years old, most of which lies underwater. Bermuda now joins the list of regions showing how much the planet still has to reveal beneath its surface.