Leaking Methane Gas From Seafloor Dissipates Quickly

So leaking gas and oil are not the big problems they are usually thought to be? Why doesn't someone propose drilling some horizontal wells, from the safety of onshore locations, out under the sea floor and tap into the source of the leaking oil and gas?
Peter


Scientists Find Good News About Methane From the Ocean Floor
December 20, 2007 SCIENTISTS FIND GOOD NEWS ABOUT METHANE BUBBLING UP FROM THE OCEAN FLOOR (source)

Methane, a potent greenhouse gas, is emitted in great quantities as bubbles from seeps on the ocean floor near Santa Barbara. About half of these bubbles dissolve into the ocean, but the fate of this dissolved methane remains uncertain. Researchers at the University of California, Santa Barbara have discovered that only one percent of this dissolved methane escapes into the air – good news for the Earth's atmosphere.
Coal Oil Point (COP), one of the world's largest and best studied seep regions, is located along the northern margin of the Santa Barbara Channel. Thousands of seep fields exist in the ocean bottom around the world, according to David Valentine, associate professor of Earth Science at UC Santa Barbara. Valentine along with other members of UC Santa Barbara's seeps group studied the plume of methane bubbles that flows from the seeps at COP.
Their results will soon be published as the cover story in Volume 34 of Geophysical Research Letters. This research effort is the first time that the gas that dissolves and moves away from COP, the plume, has been studied.
The amount of methane release from COP seeps is around two million cubic feet per day, according to Valentine. About 100 barrels of oil oozes out of this area as well. Methane warms the Earth 23 times more than carbon dioxide when averaged over a century. Thus the fate of the methane bubbles from the seeps is an important environmental question.
"We found that the ocean has an amazing capacity to take up methane that is released into it – even when it is released into shallow water," said Valentine. "Huge amounts of gas are coming up here, creating a giant gas plume. Until now, no one had measured the gas that dissolves and moves away, the plume."
Valentine hypothesized that the methane is oxidized by microbial activity in the ocean, thus relieving the ocean of the methane "burden."
To arrive at this hypothesis, Valentine and lead author Susan Mau, a postdoctoral fellow in Valentine's lab, tracked the plume down current from the seeps at 79 surface stations in a 108 square mile study area. They found that the methane plume spread over 27 square miles.
By boat, the authors sampled the water on a monthly basis. They found variable methane concentrations that corresponded with changes in surface currents. They also found that more wind releases more methane into the atmosphere. Overall, they discovered that about one percent of the dissolved methane escapes into the atmosphere in the area they studied, a long-term average. This lead the authors to hypothesize that most of the methane is transported below the ocean's surface – away from the seep area. Then it is oxidized by microbial activity.
To back up their findings of their surface sampling of the water, the scientists used a mass spectrometer hauled behind the boat as well. This equipment allowed for very high-resolution chemical information about the methane. This effort showed no significant difference in the numbers.
"We showed that the currents control the fate of the gas and supply it to bacteria in a way that allows them to destroy the methane," said Valentine.
Valentine said that while the seeps at COP are among the largest in the world, they can be found just about anywhere.
##Contact:Gail GallessichUniversity of California - Santa Barbara805-893-7220gail.g@ia.ucsb.eduThis text derived from:http://www.ia.ucsb.edu/pa/display.aspx?pkey=1704

Oil Seeps In The Gulf Of Mexico

My guess is you won't see this in the mainstream media because it doesn't fit the popular bias against the oil industry. So I'll pass this along. It is usually assumed that oil pollution in the world's oceans is caused by accidental spillage caused by drilling, production and transportation activities. The Exxon Valdez tanker spill in Alaska is the most infamous example that has tarnished the petroleum industry's reputation. These spills must be prevented and minimized as much as possible.

However, there is another side to this story. Geologists (some anyway) have long known that natural oil seeps occur, and have occurred as long as the Earth's sediments have been generating oil and gas. Oil fields leak their hydrocarbons to the surface, whether on land or beneath the oceans. Hydrocarbons are less dense than rocks and the water they contain, so the oil and gas is continually trying to escape to the surface. Eventually, given enough time, it all does.

The following satellite images from NASA prove this theory: oil and gas are always naturally leaking and "polluting" the oceans, and in a big way, as can be seen from these images. Also, consider this is going on 24 hours per day, seven days per week, 365 days per year. So maybe "big oil" companies are not the careless, evil polluters they're accused of being.

Another quite amazing thing to consider is the oceans must continually clean themselves. Somehow fish, sea plants, and corals survive. Somehow there remain pristine white sand beaches. Is the public being deceived about the damaging effects of the oil industry? I say yes.
Peter

source

Although accidents and hurricane damage to infrastructure are often to blame for oil spills and the resulting pollution in coastal Gulf of Mexico waters, natural seepage from the ocean floor introduces a significant amount of oil to ocean environments as well. Oil spills are notoriously difficult to identify in natural-color (photo-like) satellite images, especially in the open ocean. Because the ocean surface is already so dark blue in these images, the additional darkening or slight color change that results from a spill is usually imperceptible.

Remote-sensing scientists recently demonstrated that these “invisible” oil slicks do show up in photo-like images if you look in the right place: the sunglint region. This pair of images includes a wide-area view of the Gulf of Mexico from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite on May 13, 2006 (top), and a close up (bottom) of dozens of natural crude oil seeps over deep water in the central Gulf.

The washed-out swath running through the scene is where the Sun is glinting off the ocean’s surface. If the ocean were as smooth as a mirror, a sequence of nearly perfect reflections of the Sun, each with a width between 6-9 kilometers, would appear in that line, along the track of the satellite’s orbit. Because the ocean is never perfectly smooth or calm, however, the Sun’s reflection gets blurred as the light is scattered in all directions by waves.

The slicks become visible not because they change the color of the ocean, but because they dampen the surface waves. The smoothing of the waves can make the oil-covered parts of the sunglint area more or less reflective than surrounding waters, depending on the direction from which you view them.

The usual technique for mapping oil slicks from space uses radar, which bounces pulses of radio waves off the wave-roughened surface of the water and detects the amount of backscattered energy. The downside of using space-based radars to map oil slicks is that they don’t provide routine coverage of large areas, and oil slicks may evaporate or disperse significantly within a day. The researchers suggest that tracking oil slicks in the wide sunglint region of daily Terra and Aqua MODIS images may be a better avenue for comprehensive, near-real-time monitoring of large oil spills and natural seeps in marine ecosystems.

References
Hu, C., Li, X., Pichel, W.G., and Muller-Karger, F. E. (2009). Detection of natural oil slicks in the NW Gulf of Mexico using MODIS imagery. Geophysical Research Letters, 36, L01604.
NASA image created by Jesse Allen, using data obtained from the Goddard Level 1 and Atmospheric Archive and Distribution System (LAADS). Caption by Rebecca Lindsey.
Instrument:
Terra - MODIS