A camera more than a kilometer below the Pacific Ocean found a peculiar sight: a 'yellow brick road' and leaves an uncomfortable question about our seas. In 2022, a remotely-operated vehicle revealed a scene that looked like something out of a fantasy movie. On the summit of Nootka Seamount, within the vast Papahānaumokuākea Marine National Monument, a yellow brick road appeared to run across a dried lakebed on the seafloor. The scientists aboard the exploration vessel Nautilus joked about Atlantis and the road to Oz while the video streamed live online. But what did the cameras really find?
The 'road' is not a lost city. It's a result of natural geological processes. The Ocean Exploration Trust team explains that the 'tiles' are actually a fractured flow of hyaloclastite, a volcanic rock formed by hot lava meeting cold seawater during eruptions. Over time, heating and cooling stress broke the rock into sharp cracks, creating a natural mosaic resembling carefully placed bricks. It's a stunning example of ancient active volcanic geology.
This surreal landmark is located within Papahānaumokuākea Marine National Monument, a protected region covering about 582,578 square miles of the Pacific Ocean. This is larger than all US national parks combined, making it one of the largest marine conservation areas on Earth. During the Luʻuaeaahikiikekumu expedition, Nautilus explored 11 dives, mapped over 28,000 square kilometers of seafloor, and collected rock samples. These data help scientists understand the formation of ancient volcanoes and the survival strategies of deep-sea organisms.
The yellow brick road scene is just one of many discoveries, but it stands out because it makes an alien environment feel familiar. It's the kind of image that stays with you long after you see it. However, this glimpse into the deep seafloor is just a tiny fraction of what remains largely unseen.
A 2025 analysis found that the deep ocean, defined as waters 200 meters or deeper, covers about 66% of Earth, yet less than 0.001% of the deep seafloor has been visually observed. This means that the yellow brick road clip, despite its viral popularity, represents only a small part of an unmapped wilderness.
The deep ocean plays a crucial role in regulating the planet's climate by absorbing excess heat and carbon dioxide. It also supports an incredible biodiversity, from microscopic communities to undiscovered species. However, scientists warn that deep-sea pressures are increasing due to climate change, pollution, and seabed mining interests. Without baseline data, we risk damaging ecosystems we barely understand.
Missions like the Nautilus dives around Liliʻuokalani Ridge are vital. They not only gather valuable data but also make it accessible to the public through live streams and conversations. The yellow brick road encounter, for example, turns abstract statistics into something tangible, highlighting our ignorance of the deep ocean while showcasing Earth's creativity. This connection can inspire public support for protecting marine areas and exploring with local and Indigenous involvement.
In practical terms, mapping seafloor features and documenting deep-sea communities helps managers make informed decisions about human activities. The more we explore and understand, the better chance we have of preserving the deep ocean's delicate ecosystems. The path on the seafloor may not lead to Oz, but it points toward a future where the deep ocean is a shared responsibility, less mysterious and more protected.
