are relatively common throughout Illinois, but most are small, and these communities and the associated plant species seldom have been studied in detail.
It is an active hydrocarbon seep
area supporting chemoautolithotrophic communities that have been studied for various purposes for approximately 20 y.
One conclusion: A tubeworm at a hydrocarbon seep
takes between 170 and 250 years to grow 6.5 feet long.
Embryology of vestimentiferan tube worms from deep-sea methane/sulphide seeps
. Nature 381: 514-516.
Chronic exposure to all fractions of crude oil in the soil appears to have selected for greater metabolic capabilities among the soil bacteria than those found at the aquatic seeps
. When added together, hydrocarbonoclastic bacteria from soil and water at Oil Springs span a broadly diverse range of genera, probably reflecting the length of time that oil has been present at the site.
If what we observed near Svalbard occurs more broadly at similar locations around the world, it could mean that methane seeps
have a net cooling effect on climate, not a warming effect as we previously thought, said USGS biogeochemist John Pohlman, who is the papers lead author.
The research team released a report last week with some amazing news -- these tiny microbes were almost twice as many in number, in areas close to oil seeps
"There has also been significant progress on investigations into the source and cause of the oil that had been detected coming from a small number of seep
lines in the vicinity of a Frade development drilling operation," the statement said.
The Santa Barbara seeps
, for example emit 5,280 to 6,600 gallons (nearly 20 to 25 tons) of oil per day, and natural seeps
have been active for hundreds to thousands of years.
It shows the oil content of sediments is highest closest to the seeps
and tails off with distance, creating an oil fallout shadow.
Twenty-five years after discovery of these seeps
, fundamental questions still remain concerning the degree to which fauna within and around these relatively shallow communities use chemoautotrophic production as opposed to photosynthetic production (Kennicutt et al.
At some sites, the water flows from onshore aquifers to the sea through porous rocks and then seeps
up through the seafloor.