A mysterious structure emitting gas has been discovered underwater off the coast of Alaska, and its origin remains unknown.

The ocean covers a vast portion of our planet and conceals numerous mysteries beneath its depths: scientists are continually discovering new species and have still not managed to map even a third of the ocean floor. Recently, the U.S. Coast Guard, while mapping the waters off the coast of Alaska, stumbled upon a mysterious volcanic-like structure that appears to be emitting gas, reports Live Science.

It is known that the structure was discovered during an expedition aimed at mapping the Chukchi Sea and the Beaufort Sea off the Alaskan coast. Researchers collaborating with the Coast Guard reported that the structure stands approximately 500 meters tall and resembles an underwater volcano. However, scientists also state that it is too early to determine the nature of this discovery.

It is suggested that the underwater structure may be emitting gas—evidence from the water above indicates this, but researchers still cannot confirm it. The team is not yet ready to assert that the new find is an underwater volcano. Nevertheless, scientists have found that its depth is 1600 meters at its shallowest point—put simply, whatever it is, it does not pose a navigational hazard.

The previously unknown structure was discovered during a three-phase mission aboard the U.S. Coast Guard icebreaker "Healy," which is mapping the seafloor in the Chukchi Sea and the Beaufort Sea. According to the ship's commander, Megan McGovern of the National Oceanic and Atmospheric Administration (NOAA), who is a co-author of the discovery, analysis of the find is still ongoing, but the results are thrilling. Researchers also hope that this new discovery will shed light on what might be hidden on the ocean floor, much of which remains unexplored.

The team notes that the mysterious underwater structure was identified during the first phase of the expedition, which studies part of the Arctic Port Access Route Study (Arctic PARS) along the northern coast. It is expected that in the second and third phases of the mission, scientists will conduct various types of ocean research, including mapping the seafloor and taking samples to fill gaps in experts' understanding of specific areas.

According to Tim Orr, a volcanologist and geological researcher at the Alaska Volcano Observatory, who was not involved in the study, the results of this research will not be published for several more weeks, so little is currently known about the new underwater structure. Unfortunately, limited data prevents any conclusions from being drawn.

At the same time, Orr notes that young volcanoes in this region are unlikely, so the gas detected above the underwater structure may be related to processes other than volcanism. For instance, a deeply buried hydrocarbon reservoir could be the cause of its presence.

Meanwhile, Alaska does have underwater volcanoes, such as the Bogoslof volcano, but they are located in areas known for volcanism, unlike the object reported in this new study.