After effects

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Certainly. For one thing a "depleted" well, or field for that matter, is usually a financial matter - costs become larger then sales. If sales go up then the field becomes viable again.
But I suspect that you were referring to fields/wells, that after being abandoned developed significant oil so as to make it viable to re-establish the well/field. Usually a matter of either over producing the formation and abandoning as soon as production drops. Then due to normal forces oil flows into and through the formation, re charging it again, as it were.
This is becoming less common as secondary recovery methods become more sophisticated.
On the other hand Pertamina Well #1, drilled in 18-something or another, the first well in Indonesia, was still "in production" the last I heard - making less then a barrel a day :-)
Cheers,
John D. Slocomb (jdslocombatgmail)
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On Mon, 19 Jul 2010 10:47:02 +0700, J. D. Slocomb

http://www.rense.com/general63/refil.htm
rense.com
Oil Fields Are Refilling... Naturally - Sometimes Rapidly There Are More Oil Seeps Than All The Tankers On Earth By Robert Cooke Staff Writer - Newsday.com 4-10-5
Deep underwater, and deeper underground, scientists see surprising hints that gas and oil deposits can be replenished, filling up again, sometimes rapidly. Although it sounds too good to be true, increasing evidence from the Gulf of Mexico suggests that some old oil fields are being refilled by petroleum surging up from deep below, scientists report. That may mean that current estimates of oil and gas abundance are far too low. Recent measurements in a major oil field show "that the fluids were changing over time; that very light oil and gas were being injected from below, even as the producing [oil pumping] was going on," said chemical oceanographer Mahlon "Chuck" Kennicutt. "They are refilling as we speak. But whether this is a worldwide phenomenon, we don't know." Also not known, Kennicutt said, is whether the injection of new oil from deeper strata is of any economic significance, whether there will be enough to be exploitable. The discovery was unexpected, and it is still "somewhat controversial" within the oil industry. Kennicutt, a faculty member at Texas A&M University, said it is now clear that gas and oil are coming into the known reservoirs very rapidly in terms of geologic time. The inflow of new gas, and some oil, has been detectable in as little as three to 10 years. In the past, it was not suspected that oil fields can refill because it was assumed the oil formed in place, or nearby, rather than far below. According to marine geologist Harry Roberts, at Louisiana State University, "petroleum geologists don't accept it as a general phenomenon because it doesn't happen in most reservoirs. But in this case, it does seem to be happening. You have a very leaky fault system that does allow it to migrate in. It's directly connected to an oil and gas generating system at great depth." What the scientists suspect is that very old petroleum -- formed tens of millions of years ago -- has continued migrating up into reservoirs that oil companies have been exploiting for years. But no one had expected that depleted oil fields might refill themselves. Now, if it is found that gas and oil are coming up in significant amounts, and if the same is occurring in oil fields around the globe, then a lot more fuel than anyone expected could become available eventually. It hints that the world may not, in fact, be running out of petroleum. "No one has been more astonished by the potential implications of our work than myself," said analytic chemist Jean Whelan, at the Woods Hole Oceanographic Institution, in Massachusetts. "There already appears to be a large body of evidence consistent with ... oil and gas generation and migration on very short time scales in many areas globally," she wrote in the journal Sea Technology. "Almost equally surprising," she added, is that "there seem to be no compelling arguments refuting the existence of these rapid, dynamic migration processes." The first sketchy evidence of this emerged in 1984, when Kennicutt and colleagues from Texas A&M University were in the Gulf of Mexico trying to understand a phenomenon called "seeps," areas on the seafloor where sometimes large amounts of oil and gas escape through natural fissures. "Our first discovery was with trawls. We knew it was an area of massive seepage, and we expected that the oil seeps would poison everything around" the site. But they found just the opposite. "On the first trawl, we brought up over two tons of stuff. We had a tough time getting the nets back on board because they were so full" of very odd-looking sea.floor creatures, Kennicutt said. "They were long strawlike things that turned out to be tube worms. "The clams were the first thing I noticed," he added. "They were pretty big, like the size of your hand, and it was obvious they had red blood inside, which is unusual. And these long tubes -- 3, 4 and 5 feet long -- we didn't know what they were, but they started bleeding red fluid, too. We didn't know what to make of it." The biologists they consulted did know what to make of it. "The experts immediately recognized them as chemo-synthetic communities," creatures that get their energy from hydrocarbons -- oil and gas -- rather than from ordinary foods. So these animals are very much like, but still different from, recently discovered creatures living near very hot seafloor vent sites in the Pacific, Atlantic and other oceans. The difference, Kennicutt said, is that the animals living around cold seeps live on methane and oil, while the creatures growing near hot water vents exploit sulfur compounds in the hot water. The discovery of abundant life where scientists expected a deserted seafloor also suggested that the seeps are a long-duration phenomenon. Indeed, the clams are thought to be about 100 years old, and the tube worms may live as long as 600 years, or more, Kennicutt said. The surprises kept pouring in as the researchers explored further and in more detail using research submarines. In some areas, the methane-metabolizing organisms even build up structures that resemble coral reefs. It has long been known by geologists and oil industry workers that seeps exist. In Southern California, for example, there are seeps near Santa Barbara, at a geologic feature called Coal Oil Point. And, Roberts said, it's clear that "the Gulf of Mexico leaks like a sieve. You can't take a submarine dive without running into an oil or gas seep. And on a calm day, you can't take a boat ride without seeing gigantic oil slicks" on the sea surface. Roberts added that natural seepage in places like the Gulf of Mexico "far exceeds anything that gets spilled" by oil tankers and other sources. "The results of this have been a big surprise for me," said Whelan. "I never would have expected that the gas is moving up so quickly and what a huge effect it has on the whole system." Although the oil industry hasn't shown great enthusiasm for the idea -- arguing that the upward migration is too slow and too uncommon to do much good -- the search for new oil and gas supplies already has been affected, Whelan and Kennicutt said. Now, companies scan the sea surface for signs of oil slicks that might point to new deposits. "People are using airplane surveys for the slicks and are doing water column fluorescence measurements looking for the oil," Whelan said. "They're looking for the sources of the seeps and trying to hook that into the seismic evidence" normally used in searching for buried oil. Similar research on known oil basins in the North Sea is also under way, and "that oil is very interesting. There are absolutely marvelous pictures of coral reefs which formed from seepage [of gas] from North Sea reservoirs," Whelan said. Analysis of the ancient oil that seems to be coming up from deep below in the Gulf of Mexico suggests that the flow of new oil "is coming from deeper, hotter formations" and is not simply a lateral inflow from the old deposits that surround existing oil fields, she said. The chemical composition of the migrating oil also indicates it is being driven upward and is being altered by highly pressurized gases squeezing up from below. This upwelling phenomenon, Whelan noted, fits into a classic analysis of the world's oil and gas done years ago by geochemist-geologist John Hunt. He suggested that less than 1 percent of the oil that is generated at depth ever makes it into exploitable reservoirs. About 40 percent of the oil and gas remains hidden, spread out in the tiny pores and fissures of deep sedimentary rock formations. And "the remaining 60 percent," Whelan said, "leaks upward and out of the sediment" via the numerous seeps that occur globally. Also, the idea that dynamic migration of oil and gas is occurring implies that new supplies "are not only charging some reservoirs at the present time, but that a huge fraction of total oil and gas must be episodically or continuously bypassing reservoirs completely and seeping from surface sediments on a relatively large scale," Whelan explained. So far, measurements involving biological and geological analysis, plus satellite images, "show widespread and pervasive leakage over the entire northern slope of the Gulf of Mexico," she added. "For example, Ian MacDonald at Texas A&M has published some remarkable satellite photographs of oil slicks which go for miles in the Gulf of Mexico in areas where no oil production is occurring." Before this research in oil basins began, she added, "changes in reservoired oils were not suspected, so no reliable data exists on how widespread the phenomenon might be in the Gulf Coast or elsewhere." The researchers, especially the Texas team, have been working on this subject for almost 15 years in collaboration with oil industry experts and various university scientists. Their first focus was on the zone called South Eugene Island block 330, which is 150 miles south of New Orleans. It is known as one of the most productive oil and gas fields in the world. The block lies in water more than 300 feet deep. As a test, the researchers attempted to drill down into a known fault zone that was thought to be a natural conduit for new petroleum. The drilling was paid for by the U.S. Department of Energy. Whelan recalled that as the drill dug deeper and deeper, the project seemed to be succeeding, but then it abruptly ended in failure. "We were able to produce only a small amount of oil before the fault closed, like a giant straw," probably because reducing the pressure there allowed the fissure to collapse. In addition to the drilling effort and the inspection of seeps, Whelan and her colleagues reported that three-dimensional seismic profiles of the underground reservoirs commonly show giant gas plumes coming from depth and disrupting sediments all the way to the surface. This also shows that in an area west of the South Eugene Island area, a giant gas plume originates from beneath salt about 15,000 feet down and then disrupts the sediment layers all the way to the surface. The surface expression of this plume is very large -- about 1,500 feet in diameter. One surprise, Whelan said, was that the gas plume seems to exist outside of faults, the ground fractures, which at present are the main targets of oil exploration. It is suspected that the process of upward migration of petroleum is driven by natural gas that is being continually produced both by deeply buried bacteria and from oil being broken down in the deeper, hotter layers of sediment. The pressures and heat at great depth are thought to be increasing because the ground is sinking -- subsiding -- as a result of new sediments piling up on top. The site is part of the huge delta formed over thousands of years by the southward flow of the massive Mississippi River. Like other major deltas, the Mississippi's outflow structure is continually being built from sands, muds and silts washed off the continent. Analysis of the oil being driven into the reservoirs suggests they were created during the so-called Jurassic and Early Cretaceous periods (100 million to 150 million years ago), even before the existing basin itself was formed. This means the source rock is buried and remains invisible to seismic imaging beneath layers of salt. In studying so-called biomarkers in the oil, Whelan said, it was concluded that the oil is closely related to other very old oils, implying that it "was probably generated very early and then remained trapped at depth until recently." And, she added, other analyses "show that this oil must have remained trapped at depths and temperatures much greater than those of the present-day producing reservoirs." At great depth, where the heat and pressure are high enough, she explained, methane is produced by oil being "cracked," and production of gas "is able to cause sufficient pressure to periodically open the fracture system and allow upward fluid flow of methane, with entrapment of oil in its path." Copyright 2002, Newsday, Inc. http://www.newsday.com/features/ny-feat-hcov0416.story
Rense.com
Sustainable Oil? By Chris Bennett 2004 WorldNetDaily.com 7-10-4
About 80 miles off of the coast of Louisiana lies a mostly submerged mountain, the top of which is known as Eugene Island. The portion underwater is an eerie-looking, sloping tower jutting up from the depths of the Gulf of Mexico, with deep fissures and perpendicular faults which spontaneously spew natural gas. A significant reservoir of crude oil was discovered nearby in the late '60s, and by 1970, a platform named Eugene 330 was busily producing about 15,000 barrels a day of high-quality crude oil. By the late '80s, the platform's production had slipped to less than 4,000 barrels per day, and was considered pumped out. Done. Suddenly, in 1990, production soared back to 15,000 barrels a day, and the reserves which had been estimated at 60 million barrels in the '70s, were recalculated at 400 million barrels. Interestingly, the measured geological age of the new oil was quantifiably different than the oil pumped in the '70s. Analysis of seismic recordings revealed the presence of a "deep fault" at the base of the Eugene Island reservoir which was gushing up a river of oil from some deeper and previously unknown source. Similar results were seen at other Gulf of Mexico oil wells. Similar results were found in the Cook Inlet oil fields in Alaska. Similar results were found in oil fields in Uzbekistan. Similarly in the Middle East, where oil exploration and extraction have been underway for at least the last 20 years, known reserves have doubled. Currently there are somewhere in the neighborhood of 680 billion barrels of Middle East reserve oil. Creating that much oil would take a big pile of dead dinosaurs and fermenting prehistoric plants. Could there be another source for crude oil? An intriguing theory now permeating oil company research staffs suggests that crude oil may actually be a natural inorganic product, not a stepchild of unfathomable time and organic degradation. The theory suggests there may be huge, yet-to-be-discovered reserves of oil at depths that dwarf current world estimates. The theory is simple: Crude oil forms as a natural inorganic process which occurs between the mantle and the crust, somewhere between 5 and 20 miles deep. The proposed mechanism is as follows: Methane (CH4) is a common molecule found in quantity throughout our solar system - huge concentrations exist at great depth in the Earth. At the mantle-crust interface, roughly 20,000 feet beneath the surface, rapidly rising streams of compressed methane-based gasses hit pockets of high temperature causing the condensation of heavier hydrocarbons. The product of this condensation is commonly known as crude oil. Some compressed methane-based gasses migrate into pockets and reservoirs we extract as "natural gas." In the geologically "cooler," more tectonically stable regions around the globe, the crude oil pools into reservoirs. In the "hotter," more volcanic and tectonically active areas, the oil and natural gas continue to condense and eventually to oxidize, producing carbon dioxide and steam, which exits from active volcanoes. Periodically, depending on variations of geology and Earth movement, oil seeps to the surface in quantity, creating the vast oil-sand deposits of Canada and Venezuela, or the continual seeps found beneath the Gulf of Mexico and Uzbekistan. Periodically, depending on variations of geology, the vast, deep pools of oil break free and replenish existing known reserves of oil. There are a number of observations across the oil-producing regions of the globe that support this theory, and the list of proponents begins with Mendelev (who created the periodic table of elements) and includes Dr.Thomas Gold (founding director of Cornell University Center for Radiophysics and Space Research) and Dr. J.F. Kenney of Gas Resources Corporations, Houston, Texas. In his 1999 book, "The Deep Hot Biosphere," Dr. Gold presents compelling evidence for inorganic oil formation. He notes that geologic structures where oil is found all correspond to "deep earth" formations, not the haphazard depositions we find with sedimentary rock, associated fossils or even current surface life. He also notes that oil extracted from varying depths from the same oil field have the same chemistry - oil chemistry does not vary as fossils vary with increasing depth. Also interesting is the fact that oil is found in huge quantities among geographic formations where assays of prehistoric life are not sufficient to produce the existing reservoirs of oil. Where then did it come from? Another interesting fact is that every oil field throughout the world has outgassing helium. Helium is so often present in oil fields that helium detectors are used as oil-prospecting tools. Helium is an inert gas known to be a fundamental product of the radiological decay or uranium and thorium, identified in quantity at great depths below the surface of the earth, 200 and more miles below. It is not found in meaningful quantities in areas that are not producing methane, oil or natural gas. It is not a member of the dozen or so common elements associated with life. It is found throughout the solar system as a thoroughly inorganic product. Even more intriguing is evidence that several oil reservoirs around the globe are refilling themselves, such as the Eugene Island reservoir - not from the sides, as would be expected from cocurrent organic reservoirs, but from the bottom up. Dr. Gold strongly believes that oil is a "renewable, primordial soup continually manufactured by the Earth under ultrahot conditions and tremendous pressures. As this substance migrates toward the surface, it is attached by bacteria, making it appear to have an organic origin dating back to the dinosaurs." Smaller oil companies and innovative teams are using this theory to justify deep oil drilling in Alaska and the Gulf of Mexico, among other locations, with some success. Dr. Kenney is on record predicting that parts of Siberia contain a deep reservoir of oil equal to or exceeding that already discovered in the Middle East. Could this be true? In August 2002, in the "Proceedings of the National Academy of Sciences (US)," Dr. Kenney published a paper, which had a partial title of "The genesis of hydrocarbons and the origin of petroleum." Dr. Kenney and three Russian coauthors conclude: The Hydrogen-Carbon system does not spontaneously evolve hydrocarbons at pressures less than 30 Kbar, even in the most favorable environment. The H-C system evolves hydrocarbons under pressures found in the mantle of the Earth and at temperatures consistent with that environment. He was quoted as stating that "competent physicists, chemists, chemical engineers and men knowledgeable of thermodynamics have known that natural petroleum does not evolve from biological materials since the last quarter of the 19th century." Deeply entrenched in our culture is the belief that at some point in the relatively near future we will see the last working pump on the last functioning oil well screech and rattle, and that will be that. The end of the Age of Oil. And unless we find another source of cheap energy, the world will rapidly become a much darker and dangerous place. If Dr. Gold and Dr. Kenney are correct, this "the end of the world as we know it" scenario simply won't happen. Think about it ... while not inexhaustible, deep Earth reserves of inorganic crude oil and commercially feasible extraction would provide the world with generations of low-cost fuel. Dr. Gold has been quoted saying that current worldwide reserves of crude oil could be off by a factor of over 100. A Hedberg Conference, sponsored by the American Association of Petroleum Geologists, was scheduled to discuss and publicly debate this issue. Papers were solicited from interested academics and professionals. The conference was scheduled to begin June 9, 2003, but was canceled at the last minute. A new date has yet to be set. Chris Bennett manages an environmental engineering division for a West Coast technology firm. He and his wife of 26 years make their home on the San Francisco Bay.
And so on....
Gunner
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Gunner Asch wrote:

Can you say "Abiotic Oil" ?
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wrote:

This has been an on again, off again discussion for years now with much argument and theorizing on both sides. Given that (as far as I know) no one can describe the exact process that makes oil I suppose that the argument will be going on for years to come.
Cheers,
John D. Slocomb (jdslocombatgmail)
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J. D. Slocomb wrote:

Since gas well drilling and fracking started in this area, there have been several earthquakes, unheard of in these parts.
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