UPDATED: Gulf of Mexico Sheen Determined to be Sediment from Mississippi

Update: The U.S. Coast Guard has run an analysis of samples gathered from the sheen and found that is contained "only trace amounts of petroleum hydrocarbons, oil and grease." The Coast Guard added that, "at this point, the dark substance is believed to be caused by a tremendous amount of sediment being carried down the Mississippi River due to high water, possibly further agitated by dredging operations.

NOLA was reporting that the US Coast Guard was now investigating multiple reports of new oil sheen 20 miles north of the location of the 2010 Deepwater Horizon oil rig explosion.  The newly reported sheen lay about 30 miles from the Louisiana coastline and the mouth of the Mississippi river.

Photographer: Jerry Moran  (nativeorleanian.com)

Some reports on the size of the sheen stated that it was nearly 100 miles long and 12 miles wide.  According to NOLA, Paul Barnard, an operations controller for Coast Guard Sector New Orleans stated that, "We haven't been able to verify that, and it would be very unlikely for an individual to be able to observe a 100-mile long sheen."

As of today, the Coast Guard has stated that the sheen is most likely silty material stirred up from a dredging operation on the Mississippi River.  For the sake of precaution, they are having the material analyzed as it did possess a rainbow-like sheen similar to that associated with oil spills.  The Coast Guard spokesman said that it is possible that whatever the material is that is causing the sheen had been trapped in the sediment of the Mississippi's river bed, but was released by the dredging operation.