In 2022, during a survey of the Liliʻuokalani Ridge in the Papahānaumokuākea Marine National Monument (PMNM), which stretches north of the Hawaiian Islands, the research vessel Nautilus made an unexpected discovery. Scientists spotted a roadlike formation on the floor of an ancient dried-up lake, paved with something resembling yellow bricks. The PMNM is a U.S. national monument and one of the largest marine protected areas in the world, covering more area than all U.S. national parks combined. It consists of a group of small islands and atolls in the middle of the Pacific Ocean, part of the Northwestern Hawaiian Islands.
During the expedition aboard the 68-meter Nautilus, the Ocean Exploration Trust team surveyed roughly three percent of the PMNM seafloor. Working at depths between 1,000 and 3,000 meters, they captured on video what they nicknamed the “road to Oz.” Some team members even compared the formation to a “road to Atlantis,” according to ScienceAlert.
Although the lakebed sat about 1,000 meters below the surface, it looked surprisingly dry. The team said the surface resembled a baked crust that seemed like it could be cracked open. In a small area, volcanic rock had fractured in patterns that looked strikingly like bricks. They suggested the unique 90-degree fractures probably resulted from repeated heating and cooling during multiple eruptions. Those processes can create formations that look like a pathway to another world, but this is a geological feature rather than an actual road. The Nautilus team says finding the “brick road” shows they’re on the right track to learn much more about the seafloor’s hidden geology.
