The Hole Story

Seventy-one percent of the Earth’s surface is covered with oceans. Eighty percent of those tempestuous seas is completely unexplored. We like to think of outer space as the final frontier, but that’s a large swath of our home about which we know very little.

And with all those murky regions, unmapped and unseen, fantastical mysteries likely abound.

Sometimes, the incredible underwater happenings find an underlying culprit, as with our investigation of the so-called Bloop. Other times, we’re left with a conundrum. Today’s tale falls into the latter category. We cannot promise the whole story, but you will receive the hole story!

In May 2022, the National Oceanic and Atmospheric Administration launched two missions, part of the program called Voyage to the Ridge. This endeavor sent submersibles toward the Mid-Atlantic Ridge, the diverging boundary between the North American, Eurasian, and African Plates. This oceanic ridge technically forms the longest mountain chain on the planet.

The first part of the mission collected acoustic and geomorphic information from an area called the Charlie-Gibbs Fracture Zone. The second portion sent “a series of three telepresence-enabled ocean exploration expeditions” on a ship called Okeanos Explorer. This time, the mapping would be augmented by remotely operated vehicles (ROVs) to probe “unexplored and poorly understood deepwater areas of the Charlie-Gibbs Fracture Zone, Mid-Atlantic Ridge, and Azores Plateau.”

If the second leg sounds more glamorous, you’re probably onto something. This part was filled with video, including livestreams!

Any scientific enterprise of this magnitude, especially one on the ocean floor, expects to collect all sorts of new data, in addition to shooting gorgeous footage. Voyage to the Ridge produced a bona fide mystery.

A mile and a half under the surface, the cameras spied something alien. NOAA described the discovery as “sublinear sets of holes in the sediment on the seafloor.” Most things that look “manufactured” in the world are true fabrications of humans. Perfection or sharpness of geometry is extremely rare when it comes to naturally produced items. So, it was no surprise that NOAA scientists characterized the holes to look “almost human-made.”

These indentations almost look as if they were made by a machine with slots on a wheel, or something akin to a tank’s tread. However, the small piles surrounding the holes, barely evident in the zoomed photo above, indicate that something excavated these holes.

Researchers attempted to prod the holes with the ROVs, but the crafts were not designed for such a purpose. The cameras did not produce enough clarity or closeness to determine if the holes were simply indentations or if they connected to larger chambers below the top layer of the seafloor.

The oceanographers were baffled. No known organism produces holes such as these. They were so stumped that they turned to the public to produce theories that might unlock the enigma. Some ideas included previously undiscovered crab species or gas pockets poking through the sediment.

And, of course, aliens.

As the holes started to make the rounds on the internet and news media, NOAA learned that they had not actually discovered something new, after all. In 2004, scientists exploring the northern portions of the Mid-Atlantic Ridge encountered the same phenomenon.

Those researchers were also stymied when it came to determining a cause, though they proffered several hypotheses. They believe the raised sediment points toward an organism doing some excavating, maybe via an appendage that can produce rectangular cavities. The scientists dubbed the holes “lebensspuren,” which translates from German to “life traces.”

These “life traces” remind the scientists of ichnofossils – trace fossils, which are a record of biological activity but not the physical remains of an organism – found in deep marine rocks. This kind of fossil points to bioturbation, meaning a creature needed to disturb the sediment.

But what creature? Is there an unknown denizen prowling the Mid-Atlantic Ridge?

Unlike our previous ocean mystery, the Bloop, this one currently sits in the unsolved pile.

Despite the ROV’s inability to search beneath the holes, scientists did manage to collect sediment surrounding some of them. These samples included environmental DNA (eDNA), so perhaps analysis will offer some clues.

Until we learn more, however, the hole mystery remains wholly a mystery!