Gulf oil accidentMysterious flotsam in Gulf came from Deepwater Horizon rig
Scientists track debris from damaged oil rigs, helping forecast coastal impacts in the future
Shortly after the Deepwater Horizon disaster, mysterious honeycomb material was found floating in the Gulf of Mexico and along coastal beaches. Using state-of-the-art chemical forensics and a bit of old-fashioned detective work, a research team led by scientists at Woods Hole Oceanographic Institution (WHOI) confirmed that the flotsam were pieces of material used to maintain buoyancy of the pipe bringing up oil from the seafloor.
A Woods Hall Oceanographic Institute release reports that the researchers also affirmed that tracking debris from damaged offshore oil rigs could help forecast coastal pollution impacts in future oil spills and guide emergency response efforts — much the way the Coast Guard has studied the speed and direction of various floating debris to guide search and rescue missions. The findings were published 19 January in Environmental Research Letters.
On 5 May 2010, fifteen days after the Deepwater Horizon explosion, oceanographer William Graham and marine technicians from the Dauphin Island Sea Lab were working from a boat about thirty-two miles south of Dauphin Island, Alabama, when they saw a 6-mile-long, east-west line containing more than fifty pieces of white material interspersed with sargassum weed. The porous material was uniformly embedded with black spheres about a centimeter in diameter. No oil slick was in sight, but there was a halo of oil sheen around the honeycomb clumps.
Two days later, the researchers also collected similar samples about twenty-five miles south of Dauphin Island. Nobody knew what the material was, with some hypothesizing at first that it could be coral or other substance made by marine plants or animals. Graham sent samples to WHOI chemist Chris Reddy, whose lab confirmed that the material was not biological. The material’s source, however, remained unconfirmed.
In January 2011 Reddy and WHOI researcher Catherine Carmichael, lead author of the new study, collected a piece of the same unknown material of Elmer’s Beach, Grand Isle, La. In April 2011 they found several large pieces, ranging from 3 to 10 feet, of the honeycomb debris on the Chandeleur Islands off Louisiana.
Oil on all these samples was analyzed at WHOI using comprehensive two-dimensional gas chromatography. The release notes that the technique identifies the thousands of individual chemical compounds that comprise different oils from different reservoirs.
The chemistry of the oil on the debris matched that of oil sampled directly from the broken pipe from the Macondo well above the Deepwater Horizon rig.
In addition, one piece of debris from
