Some subsea plumes don't share the chemistry of BP's oil

By Janet Raloff

Web edition: June 9, 2010

During a June 8 briefing for reporters, Steven Murawski, chief science advisor for the National Oceanic and Atmospheric Administration’s Fisheries Service, described deep strata of water tainted with oil. They were identified during a recent cruise in the Gulf of Mexico. A presumption had been that any clouds of oil hovering under the surface would be plumes spewed by the damaged BP well head. But the chemical fingerprinting of diffuse undersea oil clouds at one sampling site 142 nautical miles southeast of the Deepwater Horizon accident site was “not consistent with BP oil,” he pointed out.

Which begs the question: Where did this other oil come from — since Murawski noted that earlier research surveys of the area prior to the BP spill had turned up no subsea oil clouds.

At present there is no answer. But it should be noted that some recent news organizations around the gulf coast have lately begun reporting on a second leaking offshore gulf oil rig: the Ocean Saratoga.

Citing a federal document, Ben Raines of the Mobile, Ala. Press-Register reports that this well has been leaking since at least April 30.  He quotes John Amos of Skytruth, who heads a nonprofit remote-sensing organization saying that: “We accidentally discovered this [Ocean Saratoga] spill looking at the Deepwater Horizon images. The question is, what would we see if we were systematically looking at the offshore industry?"

Good point. And Amos is only focusing on surface signs of oil. In fact, there may be plenty of hydrocarbons spewing below the surface and soiling the deep waters. Which is why a number of research groups would like to see a regular marine-monitoring network developed throughout U.S. territorial waters, especially in near-shore areas.

Aerial and satellite surveys can scan the surface to map the size and guestimate the depth of floating oil. “What we have very little information about is what happens below the surface, noted Frank Muller-Karger of the University of South Florida during a May 19 briefing before the House Subcommittee on Energy and Environment. “We have no mechanism to measure what’s going on below the surface. We have no established network . . . to see what’s going on below."

See also: Gulf gusher is far and away the biggest U.S. spill