Public release date: 13-May-2009 (from EurekAlert)
Contact: Stephanie Murphy
508-289-3340
Woods Hole Oceanographic Institution
Natural petroleum seeps release equivalent of eight to 80 Exxon Valdez oil spills
Study off Santa Barbara is first to quantify oil in sediments
A new study by researchers at Woods Hole Oceanographic Institution (WHOI) and the University of California, Santa Barbara (UCSB) is the first to quantify the amount of oil residue in seafloor sediments that result from natural petroleum seeps off Santa Barbara, California.
The new study shows the oil content of sediments is highest closest to the seeps and tails off with distance, creating an oil fallout shadow. It estimates the amount of oil in the sediments down current from the seeps to be the equivalent of approximately 8-80 Exxon Valdez oil spills.
The paper is being published in the May 15 issue of Environmental Science & Technology.
“Farwell developed and mapped out our plan for collecting sediment samples from the ocean floor,” said WHOI marine chemist Chris Reddy, referring to lead author Chris Farwell, at the time an undergraduate working with UCSB’s Dave Valentine. “After conducting the analysis of the samples, we were able to make some spectacular findings.”
There is an oil spill everyday at Coal Oil Point (COP), the natural seeps off Santa Barbara, California, where 20-25 tons of oil have leaked from the seafloor each day for the last several hundred thousand years.
Earlier research by Reddy and Valentine at the site found that microbes were capable of degrading a significant portion of the oil molecules as they traveled from the reservoir to the ocean bottom and that once the oil floated to sea surface, about 10 percent of the molecules evaporated within minutes.
“One of the natural questions is: What happens to all of this oil?” Valentine said. “So much oil seeps up and floats on the sea surface. It’s something we’ve long wondered. We know some of it will come ashore as tar balls, but it doesn’t stick around. And then there are the massive slicks. You can see them, sometimes extending 20 miles from the seeps. But what really is the ultimate fate?”
Based on their previous research, Valentine and Reddy surmised that the oil was sinking “because this oil is heavy to begin with,” Valentine said. “It’s a good bet that it ends up in the sediments because it’s not ending up on land. It’s not dissolving in ocean water, so it’s almost certain that it is ending up in the sediments.”
To conduct their sampling, the team used the research vessel Atlantis, the 274-foot ship that serves as the support vessel for the Alvin submersible.
“We were conducting research at the seeps using Alvin during the summer of 2007,” recalls Reddy. “One night during that two-week cruise, after the day’s Alvin dive was complete and its crew prepared the sub for the next day’s dive, Captain AD Colburn guided the Atlantis on an all-night sediment sampling campaign. It was no easy task for the crew of the Atlantis. We were operating at night, awfully close to land with a big ship where hazards are frequent. I tip my hat to Captain Colburn, his crew, and the shipboard technician for making this sampling effort so seamless.”
The research team sampled 16 locations in a 90 km2 (35 square mile) grid starting 4 km west of the active seeps. Sample stations were arranged in five longitudinal transects with three water depths (40, 60, and 80 m) for each transect, with one additional comparison sample obtained from within the seep field.
To be certain that the oil they measured in the sediments came from the natural seeps, Farwell worked in Reddy’s lab at WHOI using a comprehensive two-dimensional gas chromatograph (GC×GC), that allowed them to identify specific compounds in the oil, which can differ depending on where the oil originates.
“The instrument reveals distinct biomarkers or chemical fossils — like bones for an archeologist — present in the oil. These fossils were a perfect match for the oil from the reservoir, the oil collected leaking into the ocean bottom, oil on the sea surface, and oil back in the sediment. We could say with confidence that the oil we found in the sediments was genetically connected to the oil reservoir and not from an accidental spill or runoff from land.”
The oil that remained in the sediments represents what was not removed by “weathering” — dissolving into the water, evaporating into the air, or being degraded by microbes. Next steps for this research team involve investigating why microbes consume most, but not all, of the compounds in the oil.
“Nature does an amazing job acting on this oil but somehow the microbes stopped eating, leaving a small fraction of the compounds in the sediments,” said Reddy. “Why this happens is still a mystery, but we are getting closer.”
Support for this research came from the Department of Energy, the National Science Foundation, and the Seaver Institute.
The Woods Hole Oceanographic Institution is a private, independent organization in Falmouth, Mass., dedicated to marine research, engineering, and higher education. Established in 1930 on a recommendation from the National Academy of Sciences, its primary mission is to understand the oceans and their interaction with the Earth as a whole, and to communicate a basic understanding of the oceans’ role in the changing global environment.
Alaska oil seeps are widespread and numerous:
http://www.bowdoin.edu/faculty/d/dpage/alaskan_oil/
Could someone who’s much smarter than I am comment on this:
http://www.independent.com/news/2009/may/15/west-coast-threatened-human-activity/
Drill Baby Drill.
Relieve the undergroung oil pressure by extracting the oil. That will reduce the seep rate (and save GAIA).
I used to dive in that area of coal oil point for sea urchins and it was always a mess. I spoke with Fish and Game about some oil company pumping those areas of natural seepage and they speculated that if some one was to start drilling in that area they would become legally responsible for any oil spilled from the process. If you follow that line of thought its a non starter. You can’t win here in California. The greenies got it sown up no matter how your lookat it.
Hareynolds…your numbers are wrong. API=10 does equal a specific gravity of 1.0. However API of 10.3= specific gravity of 0.998. The higher the API number the lower the specific gravity. I do these kinds of calculations every day.
Jeff in Seattle…the average steel closed head barrel weighs about 37 lbs.
Drilling near natural seeps can indeed reduce the flow. Conversely, some of the secondary recovery methods such as injecting water, gas, or CO2 have actually increased the flow at the natural seeps.
There’s some irony for you,,,injecting CO2 reduces the oil viscosity and maintains reservoir pressure. One popular idea is using CO2 from power plants for secondary recovery,,,,which could increase the rate of natural seeps.
This abiotic theory pops up with irritating regularity.
Yea, there is such a thing as abiotic methane. I can tell you though, from 25 years of looking for and finding oil and gas, that most of what we produce is clearly biotic in origin.
There are complex trace long chain molecules, known as biomarkers present in the oil. They are basically fossils on a molecular level. We can trace these biomarkers directly to the source rock, and often trace then directly to the organism, and determine the age, environment of deposition of the organic matter.
I can show you side by side basins in Indonesia, one with a layer of organic rich black shale deposited in a lake 35 million years ago, and full of the fossil remains of the algea bottriococcus. The other basin lacks the organic rich layer.
Surprise! the basin with the organic layer is full of oil, and the oil is full of the same long chain hydrocarbons as the bottriococus remains. The other basin is barren.
How did those deep mantle hydrocarbons know to migrate into the basin with the algal rich rock?
I was maintaining a list of misconceptions (and why they are wrong) shouted by anti-oil people until I figured out that they don’t really care about facts. Here is some stuff about seeps:
Misconception #10. Any oil in the ocean is from a spill.
Come and listen to my story ‘bout a man named Rudesindo Cantarall. In 1971, this fisherman complained to PEMEX (the National Oil Company of Mexico) about thick tar that was fouling his nets in the Bay of Campeche. The oil people were puzzled, having no pipelines or drill rigs in that area. He took some PEMEX geologists to the spot where it was happening. What they found was natural seepage from what turned out to be one of the largest offshore oil fields ever found. It became the economic heart of Mexico’s oil industry is only now waning. Alas, Rudesindo did not retire to Acapulco Bay amongst swimin’ pools and movie stars, as we might like to believe. He died in 1997 in poverty and obscurity.
Seeps of petroleum happen anywhere petroleum occurs in abundance. It is not in the least surprising that someone would decide to drill where seeps occur. Venezuela is replete with such oil seepage and natural gas eruptions. I myself have seen these with my own eyes. In the Gulf of Mexico oil seeps out at a rate equal to 2 “ExxonValdez’s” per year (Science Daily).
So, when you see an oil platform and blame it for the tar balls on the beach, you have quite probably put cause and effect backward. Petroleum, after all is a naturally occurring substance that sometimes comes to the surface, as at the La Brea tar pits, to pick a well-known example
Misconception #11. But won’t drilling cause more seepage?
Au contrare, mon ami, pumping the oil out of the ground reduces seepage. Studies by the University of California done around an oil rig (Platform Holly) off Santa Barbara (Yes – oil platform – California) show that natural seepage has dropped by more than 50 % over 22 years as a result of oil production.
Studies of natural seepage in that area indicate that the amount of oil released in four years is equivalent to the Exxon Valdez spill.
Oh my!
Where are all the photographs of oil soaked sea birds and oil fouled [insert cute, fuzzy, doe eyed animal here] that are obvious “victims” of this catastrophe?
Wouldn’t it be cool if environmental lobbying groups were sued and forced to clean up this “mess” because they blocked drilling that would relieve the static pressure on these oil deposits and would keep them from bubbling to the surface?
From my lips (fingers) to God’s ears……..
Father Earth despoils Mother Gaia – Film at 11!
As previous comments have suggested, the solution is obvious; implement the Louisianna model.
1. Build a chain or series of drilling platforms.
2. Extract the oil – cleans up environment.
3. Realize tax revenues from that oil production.
4. When a platform stops production, cut off its legs and drop the rig.
5. Voilà, California’s own Great Barrier Reef.
6. Fishing industry booms – more tax dollars realized.
It’s a winning situation all around. Therefore, since environmentalists don’t want mankind to win, it won’t be allowed to happen.
Here’s a better idea. Environmentalists unite! Leave this modern society you so despise. Build yourselves an isolated communal retreat amongst the trees and rocks and dirt, grow your own natural organic foods, let the wife steer the plow while the husband pulls it (don’t forget animal rights!), and let the rest of society wallow in its misery of a rich productive lifestyle with all its amenities. And in fifty or so years, we can all sit back and watch on our huge flat screen TV’s, a CBS special about some strange environmentalist cult high up in the mountains living in harmony with nature and dying at the ripe old age of 46.
There is much ado about the Tar Sands (we even call them oil sands now to make them sound a little more soothing) and has been for decades. Get this!! the worry has been largely that the delicate ecology that has made the tar sands home could be compromised. We used to call this deposit, which has more reserves of oil than Saudi Arabia, the world’s largest oil spill that we were in the process of cleaning up. Clearly, an ecosystem has developed over this stuff probably beginning with evaporation of volatiles followed by bactreria that modified the surface oily sand so that it was suitable for plants and other organisms to develop. Regarding oil spills from accidents, no one likes to see birds coated with oil but it is obvious that the stuff that remains after a spill gets processed by nature.
This study of Santa Barbara oil seeps confirms prior research concerning how best to treat oil spills.
I am aware of research done by Bettelle’s Sequim, WA marine laboratory that analyzed how best to mitigate damage from oil spills. The study concluded that the best choice was to do nothing. The toxins in crude oil evaporate in one or two days. The spilled crude that is not recovered will either sink or reach shorelines where it degrades over time from various reactions and phenomena into inert tar. (excuse this layman’s recollection of details).
As I recall scientists from the Bettelle lab recommended against steam cleaning the shoreline zone of Prince William Sound after the Exxon Valdez spill. The informed responsible authorities that cleaning would destroy the biota and their habitat, especially the microorganisms that process crude oil.
Hysteria and ignorance, and the need to do something produced disastrous decision making. We know now that steam cleaning caused potentially irreparable harm to Prince William Sound. The recovery is incomplete and partial at best. Billions have been spent on cleanup and reparations. But, that is only a fraction of the true cost of the disaster, most of which could have been avoided.
So there is seepage. This is most probably caused by pressure from below. Is this pressure caused by more oil being produced/ formed by the Earth’s own complex reactions as a recent post suggested?
If this is so does it mean that ALL old oil fields are being replenished from below by Earthly processes that we barely understand? Does any body have a long “dipstick” to be able to check if old oil fields are refilling? If, after checking, we find that they are indeed refilling we should be able to work out what the maximum annual extraction should be to enable continuous (for all intents and purposes) oil production. Once we know that we should be able to work out how to use renewable energy technologies (wind, hydro, wave power, etc.) to fill the rest of our energy needs. Then the peoples of the world wouldn’t have to agonise over “peak” oil and other doom like concepts and just get on with life on this marvellous planet that fulfills all our wants and needs.
Enjoy.
Well it is only a month ago I was fishing in a middle California lake not too far from SB, and we had fossil fuels popping up allaround us in the water; lots of natural gas, and some oil too. Wouldn’t you know it, the lake is just a few miles from a sizeable oil field with literally thousands of pumps going all the time.
They haven’t started drilling under the lake yet, but there’s black gold to be had if they do.
You cannot drill for this oil because it might endanger the microbes that eat this goo.
Jack Simmons (12:30:25) :
Thomas Gold also gave credit to Russian scientists who have known this for many decades. (Russian scientists also say preparations for the coming ice age should be made). In his book he makes a good argument that hydrocarbons do not come from dead life. Hydrocarbons have been found in large quantities on planets which have no life on the surface, but like Earth may have life which feeds on existing hydrocarbons using chemical energy from sulfates or iron oxides. Gold was an astrophysicist and his theories were taken seriously by NASA in their search for extraterrestial life.
The big secret is we have a lot of oil and gas left to consume. If this were known, we would have cheap, abundant energy for the world. But that is the neo-malthusians who rule us worst nightmare, so this is suppressed. Big Oil is happy to go along with the ride since it means more profits per barrel of oil. They would rather sell 80 billion barrels of oil per year at 60 dollars a barrel than 800 billion barrels at 6 dollars a barrel.
Many of the oil wells that have been depleted have refilled (they refill slower than oil is removed allowing them to appear to be depleted) , and as Thomas Gold said, these fuels continue to upwell from the deep hot biosphere as they have for millions of years. Peak Oil is a myth on a larger scale than Alarmist warming due to CO2.
This type of statistic is well known by everyone in the biz. It does not change the fact that a huge spill all in one spot all in a short time is disastrous and may have damaging local effects lasting several decades or more. As an industry we continue to do our absolute utmost to clean up our act. There is really no excuse for terrible accidents like the Valdez except to admit that we simply must do better.
“Tim J (12:14:50) :
Just a thought to throw in the discussion:
There is the theory that oil and gas is abiotic (i.e. produced naturally beneath the earth’s crust).”
My compliments to you guys that have already responded with the geochemical evidence for the organic genesis of oil. I can only add the observations made by my petroleum geology prof back in the early 70’s.
The Soviet Union, being predisposed to state dictated science, proclaimed that petroleum was formed inorganically. This led Russia to years of abject failure in its attempts to find oil reserves. They kept looking for oil around volcanoes and other igneous features. The rest of the world was content to follow an approach that yielded immediate results – oil is produced organically. Or maybe it was more simple-minded…let’s look in places that are like the places where oil has already been found. The bottom line is that in the early 90’s Russia was bringing in American oil companies to help them find oil and gas.
And then there was the other prof who told the story of the Soviet fondness for Lamarckism. (the inheritance of acquired characteristics) Apparently this was very attractive for those with a communist view of the world. His point was that this approach was responsible for the yearly crop failures that the USSR became famous for back in the day. Meanwhile, “politically incorrect” people at places like Texas A&M were developing crops which produced surpluses we could sell to the starving Russians. They were using that other theory…natural selection.
Anyway, back to the point, don’t put your money on inorganic sourced oil…it’s been done.
And the other point: Politically dictated science is bad. It doesn’t bother me that you are intrigued by an abiotic source for hydrocarbons. It doesn’t bother me that somebody once thought that if you cut off a rat’s tail it would have short tailed babies. I’ll throw this in for the heck of it…it doesn’t bother me that my father-in-law believes he invented a perpetual motion machine but can’t quite remember how it works. It will bother me if the government dictates that I have to believe these things.
I’m surprised Steve Sadlov has not chimed in. Any Geology student from USSB will tell you that the native Chumash used tar as caulking for their ocean-going boats they navigated 20-some miles to Santa Cruz Island. Sir Francis Drake also used the tar for caulk.
25 tons per day is about 50K bbls per year. Coal Oil Point stinks and the beaches are sticky.
pft-
Continued migration of hydrocarbons does nothing to prove abiotic oil.
Sandw15 (17:25:05) :
I briefly reviewed some information a few months back on the abiotic oil theory and it was quite intriguing. Coal is certainly fossil plant sourced, but much oil comes from depths below which any organic material from the surface could descend (as I recall). It, presumably arises from carbon dissolved in the mantle rising and then forming at certain key depth and pressure environments and because it is light tends to want to rise. It will be trapped below certain geologic formations or continue to rise all the way to the surface in seeps.
I believe an employee of an oil company in the 1940’s developed the theory. That it didn’t go anywhere is not surprising since an oil company would have no interest in planting the idea in its customers minds that oil gets replenished at some level (albeit lower than the extraction rate).
I wonder if there has been any more research on this, but given that it would be anathema to the AGW funders, I don’t imagine any public funds would be provided for it.
I worked in Camarillo, CA for a few months in ’07. The wife and step-kid came out to visit over Easter and we went whale watching. We were very surprised to see so much oil in the water. It washes up on shore and there’s tar in a bunch of places. One of my shoes is still stained from it.
Lots of oil in the water out there. All 100% natural seepage…
The seeps off Santa Barbara cannot be tapped. Doing so would endanger the bacteria that feed of the leaking petroleum.
The consensus on a biological origin for petroleum hold primarily due to the presence of most reservoirs in sedimentary rock and the lack of solid evidence in an alternative explanation.
I recall learning as a graduate student of a granite hosted oil reservoir in California, but this was explained as oil migrating from its source to a suitable host – a process that is apparent in areas adjacent to oil shales (thought to the source) where the reservoir is within more porous sandstones and carbonates.
Following on from previous post (12:14:50) about abiotic hydrocarbon:
I got interested in this some years ago as I could not imagine that the quantities of oil and gas that we experience could have come solely from degraded bio-mass. It just did not gel with me and it seems many others from my bit of research.
I was therefore very interested in the Cassini mission to Titan where hydrocarbons were discovered in great abundance in many forms. It seems to me that this should be a mayor key to our understanding of the nature of hydrocarbons. So I am a little surprised I have not seen much news or comment on the results and wondering if anybody can point me to a good source.
Thanks….