Featured Research

from universities, journals, and other organizations

Subsurface oil from Deepwater Horizon spill in Gulf of Mexico, say researchers

Date:
June 9, 2010
Source:
University of South Florida
Summary:
Researchers in Florida have confirmed the presence of distinct layers of degraded oil in the deep waters of the northern Gulf of Mexico many miles from the Deepwater Horizon explosion site.

Weatherbird II sampling stations.
Credit: NOAA

Researchers at the University of South Florida's College of Marine Science have confirmed the presence of distinct layers of degraded oil in the deep waters of the northern Gulf of Mexico many miles from the Deepwater Horizon explosion site.

After a series of tests conducted by both USF and the National Oceanic and Atmospheric Administration, USF scientists are continuing research on the subsurface oil to determine if it can be conclusively linked to oil found at the surface of the gulf.

NOAA tests separately link the surface oil to the Deepwater Horizon well. The NOAA analysis was unable to directly link the subsurface samples to the Deepwater Horizon spill because the sample was too small to produce conclusive results.

"We have not concluded our comparison of the oils," said Ernst Peebles, USF's lead scientific investigator on the R/V Weatherbird II trip. "Preliminary results show similarities at least at the surface."

This research was funded by NOAA and led by Peebles, a biological oceanographer; Robert Weisberg, a physical oceanographer; chemical oceanographer David Hollander; and geological oceanographer David Naar.

Researchers discovered the subsurface oil after models developed by Weisberg, director of USF's Ocean Circulation Group, indicated that subsurface oil -- commonly referred to as "plumes" -- would have been pushed in that direction from the ruptured Deepwater Horizon well.

Degraded oil was found suspended at depths of 400 meters (one-quarter mile) and 1,000-1,400 meters (two-thirds to three-quarters of a mile) beneath the Gulf's surface in the form of small particles or droplets.

The 400-meter layer was approximately 30 meters (100 feet) thick, and was observed to extend for at least 45 nautical miles northeast of the Deepwater Horizon site.

The deeper 1,000-1,400 meters layer had hydrocarbons that looked identical to the 400 meter samples but were at twice the concentration. That layer was observed in deeper waters to the south approximately 24 nautical miles east of the Deepwater Horizon site.

During a May 22-28 trip on the R/V Weatherbird II, USF scientists discovered the 400-meter layer using a combination of 28 kHz sonar and an optical particle sensor.

The layer at 1,000-1,400 meters was located using particle-sensor data from depths below the range of the ship's sonar.

Water filtrations from both layers produced dark-colored filter pads, which proved the existence of particles or droplets without immediately revealing their composition or origin. USF scientists have since been using a variety of analytical approaches to characterize these materials, including gas chromatography/mass spectrometry, compound-specific and bulk stable isotope mass spectrometry, and optical fluorescence spectroscopy.

The gas chromatography/mass spectrometry analysis has already yielded conclusive results, indicating that the material retained on the filter pads is oil and not suspended sediments or the remains of decaying plant life.

This analysis also revealed that the smaller hydrocarbon molecules were largely missing from the deep oil, which is characteristic of oil that has been exposed to an early level of degradation by microbes. This could be taken as a good sign, as consumption of oil by microbes is one potentially important means of removing oil from Gulf waters. Future tests will be directed at determining conclusively if these deep oil layers are derived from natural seeps or from oil leaking from the Deepwater Horizon site.


Story Source:

The above story is based on materials provided by University of South Florida. The original article was written by Vickie Chachere. Note: Materials may be edited for content and length.


Cite This Page:

University of South Florida. "Subsurface oil from Deepwater Horizon spill in Gulf of Mexico, say researchers." ScienceDaily. ScienceDaily, 9 June 2010. <www.sciencedaily.com/releases/2010/06/100609102703.htm>.
University of South Florida. (2010, June 9). Subsurface oil from Deepwater Horizon spill in Gulf of Mexico, say researchers. ScienceDaily. Retrieved September 3, 2014 from www.sciencedaily.com/releases/2010/06/100609102703.htm
University of South Florida. "Subsurface oil from Deepwater Horizon spill in Gulf of Mexico, say researchers." ScienceDaily. www.sciencedaily.com/releases/2010/06/100609102703.htm (accessed September 3, 2014).

Share This



More Earth & Climate News

Wednesday, September 3, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Thousands of Fish Dead in Mexico Lake

Raw: Thousands of Fish Dead in Mexico Lake

AP (Sep. 2, 2014) — Over 53 tons of rotting fish have been removed from Lake Cajititlan in western Jalisco state. Authorities say that the thousands of fish did not die of natural causes. (Sep. 2) Video provided by AP
Powered by NewsLook.com
Raw: Iceland Volcano Spewing Smoke

Raw: Iceland Volcano Spewing Smoke

AP (Sep. 2, 2014) — The alert warning for the area surrounding Iceland's Bardarbunga volcano was kept at orange on Tuesday, indicating increased unrest with greater potential for an eruption. Smoke is spewing from the volcano, and lava is spouting nearby. (Sept. 2) Video provided by AP
Powered by NewsLook.com
U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) — The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Halliburton Reaches $1B Gulf Spill Settlement

Halliburton Reaches $1B Gulf Spill Settlement

AP (Sep. 2, 2014) — Halliburton's agreement to pay more than $1 billion to settle numerous claims involving the 2010 BP oil spill could be a way to diminish years of costly litigation. A federal judge still has to approve the settlement. (Sept. 2) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins