Ocean Asphalt Patch a Deep-Seep Mystery

Pavement-Like Material Found on Gulf of Mexico Seabed

Tubeworms that feed off chemicals grow out of a patch of asphalt on the bottom of the Gulf of Mexico. Science hide caption

See Larger Version
itoggle caption Science
Site of the asphalt seep discovery in the southern Gulf of Mexico.

Site of the asphalt seep discovery in the southern Gulf of Mexico. Science hide caption

itoggle caption Science

Scientists exploring the deep sea in the Gulf of Mexico have discovered seeps that resemble a paved road. Seeps are places where oil and other hydrocarbons bubble up from under the seabed. But these seeps, discovered by researchers with Texas A&M University at Corpus Christi, are covered in asphalt.

The seeps were found along salt domes that lie about two miles down in the southern Gulf of Mexico. Deep sea cameras revealed about 20 salt domes that had collapsed or broken apart. Along the edges were large patches of asphalt, or hardened tar. Scientists photographed them and took samples; they say the material is similar to asphalt pavement, and was probably squeezed out of the seabed like lava.

Oil seeps have been found in most of the world's oceans, but none with hardened material like this, according to a paper in this week's issue of the journal Science. The scientists also found communities of tube worms, mussels, clams and shrimp living on or near the asphalt. These animals are similar to ones living near deep sea vents, and live off of the chemicals emitted from the vents and seeps.

The asphalt deposits are the result of a violent expulsion of hydrocarbons, and indicate untapped deep-water oil reserves. Scientists had thought the region was relatively stable, but this discovery of underwater "volcanoes" shows "how much more there is to learn about the deep sea," says Texas A&M researcher Ian MacDonald. "The abundance of animal life is more proof of the adaptability of marine organisms."

Comments

 

Please keep your community civil. All comments must follow the NPR.org Community rules and terms of use, and will be moderated prior to posting. NPR reserves the right to use the comments we receive, in whole or in part, and to use the commenter's name and location, in any medium. See also the Terms of Use, Privacy Policy and Community FAQ.