An Unexpected Discovery Below the Waves
In 2022, a team aboard the Exploration Vessel Nautilus uncovered a striking geological formation on the seafloor north of Hawaii. While exploring the Liliʻuokalani Ridge in the Papahānaumokuākea Marine National Monument, researchers spotted what appeared to be a “yellow brick road”—a dry-looking, patterned rock formation over a mile beneath the ocean surface.
This peculiar site sparked immediate curiosity. The formation resembled a cobblestone path, evoking images of myth and fantasy, such as the road to Atlantis or the Emerald City from The Wizard of Oz. The visual effect was so surreal that researchers watching the live feed responded with astonishment and playful comparisons.
What It Really Is: Ancient Volcanic Geology
Despite its manmade appearance, this formation is a natural result of volcanic activity. At the summit of Nootka Seamount, the team encountered a fractured flow of hyaloclastite rock—a volcanic material created when lava explosively interacts with water or wet sediments.
“These angular, brick-like shapes are caused by heating and cooling cycles during high-energy eruptions,” experts explained.
The sharp 90-degree fractures give the rock a road-like look, as if it had been carefully laid down by human hands. However, these are simply stress fractures from multiple eruptions over time. The seemingly dry surface, despite being underwater at depths of over 3,000 meters, is due to the rugged, baked appearance of the rock.
Bringing the Deep Ocean to the Public
The Nautilus mission is run by the Ocean Exploration Trust (OET), a nonprofit that shares deep-sea exploration through public livestreams and highlight videos. Their remote-operated vehicle (ROV) captures rare geological features and unique sea creatures—giving everyday viewers an extraordinary glimpse into one of Earth’s least explored frontiers.
Past highlights have included encounters with dumbo octopuses, gelatinous deep-sea creatures, and now, this peculiar “yellow brick road.”
A Deeper Mission With Broader Goals
This discovery isn’t just visually captivating. It’s a step forward in understanding undersea geology and the diverse ecosystems of seamounts—volcanic mountains that rise from the ocean floor.
Key facts about the mission and region:
- Papahānaumokuākea Marine National Monument covers over 582,500 square miles
- It’s larger than all U.S. national parks combined
- Only about 3% of its seafloor has been explored
- Data collected helps inform conservation and marine management efforts
Beyond its mystical appearance, this formation signals a future rich with scientific potential. The Nautilus team continues to survey uncharted seafloor areas, including their recent work in the Palau National Marine Sanctuary.
“Following the yellow brick road is guiding us toward deeper understanding.”
With more missions on the horizon, the mysteries of the deep sea are slowly being revealed—one volcanic surprise at a time.
