This spring, scientists from the Monterey Bay Aquarium Research Institute (MBARI) discovered a field of ocean vents spewing super-heated water into the bottom of the ocean between Baja California and the rest of Mexico. There are plenty of these hydrothermal vents at the bottom of the ocean off the coast of North and Central America, stretching from Canada down to Costa Rica, but this one is different. For one thing, at 12,500 feet below the surface, the Pescadero Basin vents are the deepest. And its structure is one never seen in the northern hemisphere.
Most hydrothermal vents in North America are volcanic in origin and are found on top of basalt rock. Known as black smokers, they shoot out dark, mineral-rich water. These newly-discovered towering vent chimneys, though, are white, and are made up of calcium carbonate, formed when super-hot water (as high as 554 degrees Fahrenheit) emerged from the sea floor and mixed with frigid ocean water. Unlike the basalt vents, they emit clear hot water rather than black smokey liquid.
“This is the weirdest thing I’ve ever seen on the bottom of the ocean,” Robert C. Vrijenhoek, a senior scientist and biologist at MBARI, tells mental_floss.
The odd vents also feature unusual marine life rare to other locales. They’re covered in organisms, especially tubeworms of the genus Oasisia. “They cover the carbonate chimneys top to bottom, as high as 30 meters [98 feet],” Vrijenhoek says. “It’s like a garden of red flowers. It’s incredible.”
Vrijenhoek and his colleagues are still classifying the exact species present at the Pescadero Basin vents. Though found elsewhere in the world, the tubeworms, clams, squat lobsters, and other life that cling to the vents appear in larger numbers in the Pescadero Basin than have been observed elsewhere, while common vent animals like riftia tubeworms are rare, for reasons the scientists cannot yet fully explain. “This unique depth and chemistry has favored a subset of species that might not be common elsewhere,” Vrijenhoek says.
However, they do have some clues. “We think this deep basin [the vents are] located in doesn’t have an ocean crust layer,” hypothesizes marine geologist Dave Clague, a senior scientist at MBARI who led the project. “It’s essentially mantle rock that’s exposed,” he guesses. There are similar crust-less spots in the Indian Ocean and the mid-Atlantic, but this would be the first spot where the mantle is covered by hydrothermal vents and, of course, the resulting towers upon towers of tubeworms.
[h/t: National Geographic]
All images (c) 2015 MBARI