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=== Diamondoids ===
=== Diamondoids ===
Tiny diamondoids occur in oils and condensates. They have similar [[diamond]] structure and suspected to have similar origins related to [[kimberlite]] diamond deposits, from hot and high pressure rocks in the earth´s mantle.
Tiny diamondoids occur in oils and condensates. They have similar [[diamond]] structure and suspected to have similar origins related to [[kimberlite]] diamond deposits, from hot and high pressure rocks in the earth´s mantle. <!-- shocking truth guys! These microdiamonds might come from the drill bits used to drill the holes! Holy snapping duck shit! ~ Rolinator -->


=== Hydrogen ===
=== Hydrogen ===

Revision as of 05:00, 27 December 2005

The hypothesis of abiogenic petroleum origin (synonyms: abiotic, abyssal, endogenous, inorganic, juvenile, mineral, primordial) holds that petroleum is formed by non-biological processes deep in the earth's crust and mantle. It contradicts the more widely-held view that petroleum is a fossil fuel produced from the remains of ancient living organisms. The constituent precursors of petroleum (mainly methane) are commonplace and it is possible that appropriate conditions exist for hydrocarbons to be formed deep within the earth. This hypothesis dates to the 19th century, when the French chemist Marcellin Berthelot and the Russian chemist Dmitri Mendeleev proposed it, and was revived in the 1950s.

"The capital fact to note is that petroleum was born in the depths of the earth, and it is only there that we must seek its origin." (Dmitri Mendeleev, 1877)[1]

Russian geologist Nikolai Alexandrovitch Kudryavtsev was the first to propose the modern abiotic theory of petroleum in 1951. He analyzed the geology of the Athabasca Tar Sands in Alberta, Canada and concluded that no "source rocks" could form the enormous volume of hydrocarbons, and that therefore the most plausible explanation is abiotic deep petroleum. The Russian-Ukrainian theory of petroleum, based on thermodynamic calculations made for the first time by the Ukrainian scientist, Prof. Emmanuil B. Chekaliuk (1967), contends that petroleum is formed at high pressure and temperature in the earth's mantle, out of inorganic carbon never part of animals or plants. This theory is said to be supported by experimental studies conducted by Dr J.F. Kenney and his Russian colleagues. Their conclusions about petroleum origin are also said to vindicate the theories propounded by Kudryavtsev.

Although this theory is supported by a large minority of geologists in Russia and Ukraine, where it was intensively developed since the 1950s, it has only recently begun to receive attention in the West, where the biogenic petroleum theory is still believed by the vast majority of petroleum geologists. Kudryavtsev's work was continued by a constellation of bright researchers — Petr N. Kropotkin, Vladimir B. Porfir'ev, Emmanuil B. Chekaliuk, Vladilen A. Krayushkin, Georgi E. Boyko, Georgi I. Voitov, Grygori N. Dolenko, Iona V. Greenberg, Nikolai S. Beskrovny, Victor F. Linetsky and many others. Their pupils and schools have successfully developed in spite of steady resistance from powerful opponents. The torch of abiogenic knowledge has now been taken up by the third generation of scientists in the CIS countries and abroad. Planetary scientist Thomas Gold was one of the abiogenic theory's most prominent proponents in recent years in the West.[2] Although it was originally denied that abiogenic hydrocarbons exist at all on Earth, this is now accepted by Western geologists. The orthodox and widely accepted position now is that while abiogenic hydrocarbons exist (in inverse proportion to hydrocarbon chain complexity), they are not produced in commercially significant quantities.

A variation of the abiogenic theory includes alteration by microbes similar to those which form the basis of the ecology around deep hydrothermal vents.

One prediction of most abiogenic theories is that other planets of the solar system or their moons have large petroleum oceans, either from hydrocarbons present at the formation of the solar system, or from subsequent chemical reactions.

One indication that this theory is receiving increasing attention from Western geologists is indicated by the conference of the American Association of Petroleum Geologists designed by Michel T. Halbouty was scheduled previously for June 2003 in London than postponed to July 2004 in Vienna, entitled "Origin of Petroleum—Biogenic and/or Abiogenic and Its Significance in Hydrocarbon Exploration and Production". Several considerations caused it to be cancelled. Instead, AAPG held a one day session on the topic just prior to the June 2005 annual meeting in Calgary, Alberta.[3]

Comparison of theories

There are two theories about the origin of carbon fuels: the biogenic theory and the abiogenic theory. These theories have been intensely debated since the 1860s, shortly after the discovery of widespread petroleum deposits. The following sections highlight the main differences between the two theories.

Raw material

  • Biogenic: remnants of buried plant and animal life.
  • Abiogenic: deep carbon deposits from when the planet formed or subducted material.

Events before conversion

  • Biogenic: Organic matter consisting of dead plants and animals is deposited and buried. Accumulating sediments compress the material over geologic time scales. At a depth of several hundred meters, heat and pressure convert it to bitumens and kerogens.
  • Abiogenic: At depths of hundreds of kilometers, carbon deposits are a mixture of hydrocarbon molecules which migrate upward through the crust. Much of the material becomes methane.

Conversion to petroleum and methane

  • Biogenic: Time and temperature crack kerogens into the hydrocarbons that comprise petroleum in a process called catagenesis.
  • Abiogenic:
    1. When the material passes through temperatures at which extremophile microbes can survive some of it will be consumed and converted to heavier hydrocarbons.
    2. Another formulation of abiogenic origin theory sees microbial life strictly as a contaminant, unnecessary to account for any "biomarkers" supposedly supporting biogenic origins.[4] The full suite of hydrocarbons found in petroleum is generated at depth by abiogenic processes,[5] and therefore shallow petroleum deposits represent the simple displacement of those hydrocarbons from their formation environment.

Formation of coal

  • Biogenic: Coal is organic material which was buried and compressed.
  • Abiogenic: Coal is organic material which may be filled with hydrocarbons which seeped into the deposit. This can happen on the surface, such as in a swamp with methane and petroleum seeps.

Evidence supporting abiogenic theory

Supergiant oil fields

Russian geologist Nikolai Kudryavtsev was also a prominent and forceful advocate of the abiogenic theory. He argued that no petroleum resembling the chemical composition of natural crudes has ever been made from plant material in the laboratory under conditions resembling those in nature.

He gave many examples of substantial and sometimes commercial quantities of petroleum being found in crystalline or metamorphic basements, or in sediments directly overlying those. He cited cases in Kansas, California, western Venezuela and Morocco. He also pointed out that oil pools in sedimentary strata are often related to fractures in the basement directly below. This is evidenced by the Ghawar supergiant oil field (Saudi Arabia); the Panhandle Field in Kansas (United States), which also produces helium; the Tengiz Field (Kazakhstan); the White Tiger Field (Vietnam); and innumerable others. The Lost Soldier Field in Wyoming has oil pools, he stated, at every horizon of the geological section, from the Cambrian sandstone overlying the basement to the upper Cretaceous deposits. A flow of oil was also obtained from the basement itself. Hydrocarbon gases, he noted, are not rare in igneous and metamorphic rocks of the Canadian Shield. Petroleum in Precambrian gneiss is encountered in wells on the eastern shore of Lake Baikal. He stressed that petroleum is present, in large or small quantity, but in all horizons below any petroleum accumulation, apparently totally independent of the varied conditions of formation of these horizons. This statement has since become known as "Kudryavtsev's Rule" and many examples of it have been noted in different parts of the world. He concluded that commercial accumulations are simply found where permeable zones are overlaid by impermeable ones. - Kudryavtsev introduced a number of other relevant considerations into the argument. Columns of flames have been seen during the eruptions of some volcanoes, sometimes reaching 500 meters in height, such as during the eruption of Merapi in Sumatra in 1932. (There have been several other instances subsequently.) The eruptions of mud-volcanoes have liberated such large quantities of methane that even the most prolific gasfield underneath should have been exhausted long ago. Also the quantities of mud deposited in some cases would have required eruptions of much more gas than is known in any gasfield anywhere. The water coming up in some instances carries such substances as iodine, bromine and boron that could not have been derived from local sediments, and that exceed the concentrations in seawater one hundred fold. Mud volcanoes are often associated with lava volcanoes, and the typical relationship is that where they are close, the mud volcanoes emit incombustible gases, while the ones further away emit methane. He knew of the occurrence of oil in basement rocks of the Kola Peninsula, and of the surface seeps of oil in the Siljan Ring formation of central Sweden. He noted as mentioned above that the enormous quantities of hydrocarbons in the Athabasca tar sands in Canada would have required vast amounts of source rocks for their generation in the conventional discussion, when in fact no source rocks have been found.

Extraterrestrial methane

Methane and many other hydrocarbons have been detected at several locations throughout the solar system. Methane is a common component in the makeup of the cosmos, and was likely incorporated into the earth during formation. Alternatively, it may be delivered to Earth in abundance by chondrite meteorites. Extraterrestrial methane is apparently created by abiogenic processes, except possibly on Mars, where extraterrestrial biology may be involved.


Existence of hydrocarbon deposits

The world’s conventional oil reserves should disappear in no more than one million years, based upon the rate of hydrocarbon seepages.[6] If there is a limited source of hydrocarbon deposits, in geologic time frames, it is an extraordinary coincidence that deposits exist now. If such deposits are being replenished, their existence becomes less surprising. A crucial question to the bio-organic concept how it may support any mechanism for supplying oil reserves faster than they decay. Geological facts collected from all petroleum-prone basins testify that geologically oil and gas fields were formed very rapidly that contradicts that very protracted period of organic rocks maturation and stadial hydrocarbon migration predicted by bio-organic concept. It is a fundamental observation and main geological contradiction to the conventional bio-organic model.

Basic outgassing regimes

One believes that abiogenic origin has a hard time explaining why hydrocarbon deposits are not far more widespread than they are as any significant abiogenic source would be quite markedly very large scale. Thinking that mantle volatiles are allegedly rare in the superficial layers of the Earth’s surface it is worth to take into account that solid rocks of lower crust and upper mantle cover vast areas of the dryland (e.g. granulite and ophiolite belts). Moreover, mantle rocks crop out on the ocean floor along the global system of mid-oceanic ridges engirding this planet. Also, it is often supposed that the likes of earthquakes would cause massive discharge of hydrocarbons (for example, catastrophic 'oil slicks' in oceans) by rupturing impervious cap rocks. Nevertheless, it is necessary to consider the role of everyday and steady global fluid upward seeping, or so-called cold outgassing, that drives as much as or even much more that catastrophic events. - It is thought this is a somewhat misleading argument because there are evidence of fossil tar pits over a wide range of periods and indeed many of them are important sources of fossils. This indeed proves replenishment of sediments with fossil organic matter through geological time (hundred of millions of years) which biogenic origin only can easily explain. However, it has nothing in common with rapid formation of oil and gas fields (~10-40 thousands of years) and geologically rather fast decay. Moving to the daylight surface (ultimate reservoir and dead end for petroleum) hydrocarbons are quickly disappearing while dissipation, evaporation, extensive oxidation and deep bio-degradation. So the clue to the solution of this problem is in global carbon and hydrogen balance, the flow and exchange rates.

Methane on Earth

Methane is typically found on Earth, when not in natural gas deposits, in methane hydrate deposits under high pressure under the deep abyssal plains of oceans, produced from the decay of sinking biotic materials at shallow levels. Methane's effect as a greenhouse gas is twenty times greater than carbon dioxide. It is possible that major extinction in the history of the earth is due to methane. During the breakup of supercontinent Pangaea in the Triassic Period, an enormous volume of methane was released to the atmosphere. Methane reacts with oxygen yielding carbon dioxide in magmatic volcanoes. Methane reacts with oxygen and calcium forming carbonate cements in sedimentary reservoirs with petroleum. Methane feeds bacterial ecosystems, chemosynthetic communities and deep-water or cold water corals that live on the ocean floor. Methane is the main gas that is released by mud volcanoes, eventually accompanied by helium, nitrogen and brines with bromine, iodine and liquid bitumen. Methane displacement at great depths may be a cause of earthquakes. Methane can polymerize by Fischer-Tropsch synthesis forming gas to liquids natural hydrocarbons in earth's mantle or through serpentinization of peridotites that yield hydrogen in presence of catalyst metals such as nickel, iron, and form natural petroleum. Methane acts on organic rich shales and produces a minor contribution (1-3%) to form petroleum with true biomarkers as hopanoids and others insaturated hydrocarbons (n-alkenes) from bacteria. Methane interacts with peats, forming coal and bearing mercury, nickel, arsenic, cadmium, selenium, vanadium, uranium and other toxic heavy metals. Methane has a wide range of thermodynamic stability. Methane flares can be a cause of aerial disasters. Thomas Gold's formulation of the abiogenic theory of petroleum origin requires primordial methane from the earth's formation or early history. However, new experiments demonstrate that hydrocarbons will be generated spontaneously from other carbon sources, such as calcium carbonate, at pressures found in the earth's mantle.

Extraterrestrial methane has been detected on or in:

In 2004, the Cassini spacecraft confirmed a hydrocarbon weather system on Titan. It should be noted, however, that the Titanian hydrocarbon system is a photocatalyzed methane/ethane equilibrium of a kind which cannot exist in Earth's oxygen-rich atmosphere.

Cold planetary formation

In the late 19th century it was believed that the earth was extremely hot, possibly completely molten, during its formation. One reason for this was that a cooling, shrinking, planet was necessary in order to explain geologic changes such as mountain formation. A hot planet would have caused methane and other hydrocarbons to be outgassed and oxidized into carbon dioxide and water, thus there would be no carbon remaining under the surface. Many planetary scientists now believe that formation was a relatively cool process until radioactive materials accumulated together deep in the planet.

  • Recent testing of a zircon, at 4.4 billion years old the world's oldest rock, suggests rocks which formed at temperatures low enough for liquid water. The Moon formed only shortly before this time. [7]

Unusual deposits

Hydrocarbon deposits have been found in places that are said to be poorly explained by biogenic theory. Some oil fields are being refilled from deep sources, although this does not rule out a deep biogenic source rock. In the White Tiger field in Vietnam and many wells in Russia, oil and natural gas are being produced from reservoirs in granite basement rock. In the Vietnamese case, this rock is believed to have no oil-producing sediments under it, so the biogenic theory requires the oil to have migrated laterally dozens of kilometers along faults from source rock.

Deep microbes

Microbial life has been discovered 4.2 kilometers deep in Alaska and 5.2 kilometers deep in Sweden. Methanophile organisms have been known for some time, and recently it was found that microbial life in Yellowstone National Park is based on hydrogen metabolism. Other deep and hot extremophile organisms continue to be discovered. Proponents of abiogenic petroleum origin contend that deep microbial life is responsible for the biomarkers (see below) that are generally cited as evidence of biogenic origin. U.S. Geological Survey (USGS) scientist Frank Chapelle and his colleagues from the USGS and the University of Massachusetts have discovered a potential analog for life on other planets. A community of Archaea bacteria is thriving deep in the subsurface source of a hot spring in Idaho. Geothermal hydrogen, not organic carbon, is the primary energy source for this methanogen-dominated microbial community. This is the first documented case of a microbial community completely dominated by Archaea.[8]


Helium

Helium gas has close association with petroleum. Although ³He is primordial, much He gas is from radioactive decay of uranium. Helium gas is associated with light oils, sometimes accompanied by nitrogen that allow petroleum to reach shallow levels in crust.

Trace metals

Nickel (Ni),vanadium (V),lead (Pb),arsenic (As),cadmium (Cd),mercury (Hg) and others metals frequently occur in oils. Some heavy crude oils, such as Venezuelan heavy crude have up to 45% vanadium pentoxide content in their ash, high enough that it is a commercial souce for vanadium. These metals are common in Earth's mantle, thus their compounds in oils are often called as abiomarkers.

Analysis of 22 trace elements in 77 oils correlate significantly better with chondrite, serpentinized fertile mantle peridotite, and the primitive mantle than with oceanic or continental crust, and shows no correlation with seawater. [9]

Diamondoids

Tiny diamondoids occur in oils and condensates. They have similar diamond structure and suspected to have similar origins related to kimberlite diamond deposits, from hot and high pressure rocks in the earth´s mantle.

Hydrogen

Petroleum is composed mainly of n-alkanes. Sir Robert Robinson, Nobel Laureate in chemistry, studied the chemical makeup of natural petroleums in great detail, and concluded that they were mostly far too hydrogen-rich to be a likely product of the decay of plant debris. Olefins, the unsaturated hydrocarbons, would have been expected to predominate by far in any material that was derived in that way. He also wrote: "Petroleum ... [seems to be] a primordial hydrocarbon mixture into which bio-products have been added."

Thermodynamics

The Second Law of Thermodynamics prohibits spontaneous generation of hydrocarbons heavier than methane at low pressures; Thermodynamic calculations and experimental studies confirm that n-alkanes (common petroleum components) do not spontaneously evolve from methane at pressures typically found in sedimentary basins, and so the theory of an abiogenic origin of hydrocarbons suggests deep generation (below 200 km [10].)

Biology

Life as we know it is primarily based on carbon. The first living organism's (archaeobacteria) food energy came from primordial methane or petroleum (hydrocarbons) in the depths. They live deep in the crust and formed oil contaminants which became parts of biomarkers found in natural petroleum. Photosynthesis is a complex process that primitive organisms developed to help survive on the surface of the planet. This occurred through evolution as food sources dwindled when local hydrocarbon upwelling ceased. Then, as said by Astrophysicist Thomas Gold, primitive bacteria invented photosynthesis to make their own food. (see autotrophs)

Serpentinization and chemical synthesis of oil

Deep sea vent biogeochemical cycle diagram

Another possible formation of inorganic oil is via Fischer-Tropsch Synthesis. The Fischer-Tropsch process converts carbon dioxide, carbon monoxide, and methane into liquid hydrocarbons of various forms. The carbon dioxide and carbon monoxide is generated by partial oxidation of coal and wood-based fuels. This process was developed and used extensively in World War II by Germany, which had limited access to crude oil supplies. It is today used in South Africa to produce most of that country's diesel from coal. Since there are large but finite coal reserves in the world, this technology could be used as an interim transportation fuel if conventional oil were to disappear. There are several companies developing the process to enable practical exploitation of so-called stranded gas reserves, those reserves which are impractical to exploit with conventional gas pipelines and LNG technology.

Serpentinization of carbon-rich peridotite ultramafic rocks involving Fischer-Tropsch reactions are thought to occur within the crust of the earth when mantle peridotite is hydrolysed becoming serpentinite while releasing hydrogen. In the presence of catalyst transition metals (e.g. Fe, Ni) hydrogen reacts with carbon dioxide from carbonate rocks and results in n-alkane hydrocarbons, including linear saturated hydrocarbons, alcohols, aldehydes, ketones, aromatics, and cyclic compounds.[11] Nanodiamonds in mineral fuels suggest contact with material with such a deep hot history. Where hydrocarbon fluids encounter shelf limestones, extensive replacement reactions occur which form large volumes of hydrothermal dolomite.[12]

Deep structures and petroleum association

Oil and gas fields are mainly found over deep, fractured basement structures in the earth such as plate boundaries and meteorite impact craters. This association can be observed in the distribuition of oil fields along the arcs, for instance, of Indonesia, the Persian Gulf, the Apennines in Italy, Alaska, and the Barbados Arc continuing towards Trinidad and Tobago and Venezuela.

Why is oil frequently found in sedimentary basins?

Sedimentary basins fill and cover depression areas where occurred deep faults associated with plate limits (rifts, convergent subduction or collision between two plates) and sedimentary strata form good reservoirs (pore spaces) and seals that trap hydrocarbons and these reservoirs are connected to deep sources through deep faults. Petroleum also occurs in the crystalline basement, though large accumulations are rare. Hydrocarbons rise from great depth due to their buoyancy, accumulating when they encounter impermeable caprock such as shale. These accumulations within porous strata are the most economical places to mine petroleum. Traditional biogenic theory also predicts such accumulations in sedimentary strata (as a formation environment), so a confirmation bias may have developed in the oil exploration industry. Most fluid motion within rock occurs along fractures, so hydrocarbons preferentially rise through the deep fracture networks associated with plate boundaries, because these mega structures reach Earth's mantle.

Ambiguous results

- Ongoing research has changed the status of some information. For example, the evidence of some biomarkers which were interpreted as supporting the biogenic theory has been undermined by finding similar materials in thermophilic bacteria which are part of abiogenic theories.

Biomarkers or Chemofossils

Chemicals of biological origin have been found in many geologic hydrocarbon deposits. These biomarkers were believed to be from known surface sources. Due to the difficulty in culturing and sampling deep heat-loving bacteria, thermophiles, little was known of their chemistry. As more is learned of bacterial chemistry, more biomarkers seem likely to be due to bacterial action. Hopanoids, called the "most abundant natural products on Earth", were believed to be indicators of oil derived from ferns and lichens but are now known to be created by many bacteria, including archaea. Sterane was thought to have come from processes involving surface deposits but is now known to be produced by several prokaryotes including methanotrophic proteobacteria. Thorough rebuttal of biogenic origins based on biomarkers has been offered by Kenney, et al. (2001).[4]

A general summary of commonly cited biomarkers follows. Claims that the presense of such biomarkers in petroleum indicates biogenic origin may be found in most modern, English language textbooks on petroleum.

Organic compounds

Biogenic: Rare organic compounds found in both petroleum and biological matter illustrate that the former comes from the latter. These include terpenoids, terpenes, pristane, phytane, cholestane, and most impressively, chlorins and porphyrins, which are large, chelating molecules in the same family as heme and chlorophyll.

Abiogenic: Each of the chemicals has been observed in carbonaceous chondrite meteorites, immediately disproving any biological association. Cholestane is very similar to the biological chemical cholesterol, however, the latter has never been found in petroleum. Porphyrins, in particular, were observed in the Orgueil meteorite as early as 1964,[13] and produced by abiogenic means mimicking the Earth in 1967.[14] Furthermore, the chelated metal element is always magnesium in chlorophyll, and iron in heme. Porphyrins found in petroleum are usually chelated with vanadium or nickel.[4]

Odd-number carbon abundance

Biogenic: Members of the n-alkane series found in petroleum have a slighlty greater abundance of odd-numbered carbon chains (propane, pentane, etc.) Likewise, linear carbohydrate molecules in living systems exhibit the same preference for odd carbon numbers. In the biogenic framework, the former seems to come from the latter.

Abiogenic: All populations of linear hydrocarbon chains, be they artificial, natural, or biological, exhibit this tendency. It arises from the geometry of the covalent bond in linear molecules.

Chirality

Biogenic: The presense of optical activity in petroleum indicates biological origin, because biological compounds are known to exhibit left-handed chirality.

Abiogenic: The idea that optical activity implies biology is a relic dating from the founding work of Louis Pasteur, who first explained the polarization of light in wine in terms of chirality. The study of stereochemistry has revealed that many natural systems, including hydrocarbons in primordial meteorites, possess an imbalance of chirality that results in optical activity. Petroleum may have right- or left-handed optical activity, which contrasts with biological systems' exclusive left-handed chirality. This distinction has led to chirality being regarded as an abiomarker among proponents of the abiogenic theory.

Deep hot carbon sources

Carbonate lava

Carbonatites are intrusive carbonate mineral-rich igneous rocks. Although they are deposits of carbon from an igneous source, the geology behind their creation is not understood. Hydrocarbon-saturated fluid inclusions are typical for carbonatites as for igneous alkaline rocks as well.

Hydrothermal vents

Hydrothermal vents expel mineral-rich geothermally heated water.

  • Carbon dioxide abiogenically produced from magma: As magma outgasses helium and carbon dioxide at depths less than 60 km, there should be deep carbon fluids present in areas such as oceanic ridges where the magma is able to heat surface waters.
  • Microbes can create methane: Extremophile methanogens such as Methanopyrus can convert carbon dioxide to methane.
  • Methane can also be created chemically: Iron in rock can release hydrogen from water, then carbon dioxide can combine with the hydrogen to produce methane and water. University of Minnesota researchers discovered that rocks rich in chromium minerals can encourage chemical methane production, while also producing the more complex hydrocarbons ethane and propane.
  • Methane and carbon dioxide may be dissolved in water which enters hydrothermal vent systems.
  • Hydrothermal vents might release methane and carbon from deposits of biological origin, although this is less likely in vents at spreading oceanic ridges.

Evidence supporting biogenic theory

Unusual deposits

While it is true that some oil fields do not conform to the standard model of a fixed amount of oil trapped in a sedimentary basin, these examples are accommodated by the biogenic model. For example, the White Tiger field (Cuu Long Basin) cited above is located in an area where significant normal faulting brings relatively young sedimentary rocks into contact with older, fractured horst blocks of igneous rocks.[15] The produced oil is described as typically lacustrine (derived from lake deposits), consistent with the migration of hydrocarbons from the organic-rich sediments into the fractured basement.

In Eugene Island 330, a large production area of that is currently being recharged, a deep source rock is indicated, and the chemical composition of the recharging oil strongly indicates that it is leaking from a deep, intermediate reservoir.

US continuous hydrocarbon reservoirs.

One type of unusual deposit that one might to expect to find if the abiogenic hypothesis is true would be hydrocarbons trapped in sedimentary basins that do not contain conventional source rocks. Evidence for such deposits is lacking. Many economically disappointing wells have been drilled into geologic structures that would be expected to trap hydrocarbons, but there are no hydrocarbons present. Oil companies have learned that an appropriate source rock is necessary before they will commit to drilling a well in a potential new field.

Biomarkers

It has been argued that the abiogenic theory does not explain the detection of various biomarkers in petroleum. Microbial consumption does not yet explain some trace chemicals found in deposits. Materials which suggest certain biological processes include tetracyclic diterpane and oleanane. Although extremophile microorganisms exist deep underground and some metabolize carbon, some of these biomarkers are only known so far to be created in surface plants. This evidence is consistent with the biogenic hypothesis, although it might be true that these hydrocarbons have merely been in contact with ancient plant residues. There also is evidence that low-temperature relatives of hyperthermophiles are widespread, so it is also possible for biological deposits to have been altered by low-temperature bacteria which are similar to deeper heat-loving relatives. One study found diamondoids in oil show high levels of carbon isotopic fractionation the same as most true biomarkers, indicating diamondoid derivation from enzymatically-created lipids.[16]

Petroleum origin, peak oil, and politics

Many aspects of the abiogenic theory were developed in the former Soviet Union by Russian and Ukrainian scientists during the Cold War. Some proponents see a pro-Western bias in the promotion of the biogenic theory. Thus, in addition to the scientific merits of competing hypothoses, political and economic considerations often influence discussions of petroleum origins.

The topic of the origin of petroleum is also linked to discussions of projected declines in petroleum production, variously referred to as "peak oil" or "Hubbert's peak". Some environmentalists accuse abiogenic theory supporters of a "cornucopian" worldview. They claim that such a view incorrectly sees no limits to exploitation of petroleum supplies while simultaneously ignoring potential consequences of petroleum consumption such as global warming. Conversely, some supporters of the abiogenic theory accuse their opponents of an unwarranted Malthusian viewpoint that needlessly limits the use of hydrocarbons as an energy source and artificially inflates oil prices.


Independent of whether massive hydrocarbon reserves exist deep in the crust, they are unattainable in the short term. Considering the apparent dominance of the biogenic origin theory in the exploration industry, new oil discoveries based on abiogenic theory may be slow in coming. The ASPO predicts that global oil production will peak in 2007, while some other organizations such as the USGS pick as late as 20 years later. Whenever it may happen, it is unlikely that the serious economic ramifications of peak oil can be avoided. For this reason, as well as concerns about global warming, development of nuclear power and renewable energy sources continues at an accelerating pace.

These aspects of the controversy may be seen in many of the online articles in the External links section below.

The future of the abiogenic theory

Apart from the Russian interest, active proponents of the abiogenic theory in the west have all but disappeared. Thomas Gold died in 2004, with apparently none of his students following up on his research. Conspiracist Joe Vialls [17] died in 2005. The passing of the torch may go to Dr. Jerome R. Corsi, author of "Black Gold Stranglehold", or Dr. Jack Kenney of Gas Resources Corporation[18](see references). Nevertheless, the theory has received continued attention in the media and scientific organizations (note external links). One session of the AAPG's 2005 conference was devoted to the subject, indicating serious professional interest [19]. The results of the Cassini-Huygens mission to Titan (a moon of Saturn) indicated the existence of hydrocarbons, mainly methane. This can be interpreted as support for an abiogenic petroleum origin on a cool early Earth. Studies of ocean floor hydrothermal vents as in the Lost City hydrothermal field; mud volcanoes; mantle peridotite serpentinization; hydrocarbons in meteorites; experimental studies of abiogenic methane generation; reworking primordial hydrocarbons by bacteria; the association of the gases helium and nitrogen in many oil fields; and the presence of trace metals related to Earth's mantle (Ni, V, Cd, As, Pb, Zn, Hg and others); will permit a better understanding of the origin of natural hydrocarbons in the earth.

See also

References

  1. ^ Mendeleev, D., 1877. L'origine du petrole. Revue Scientifique, 2e Ser., VIII, p. 409-416.
  2. ^ . ISBN 0387985468. {{cite book}}: Missing or empty |title= (help); Unknown parameter |Author= ignored (|author= suggested) (help); Unknown parameter |Publisher= ignored (|publisher= suggested) (help); Unknown parameter |Title= ignored (|title= suggested) (help); Unknown parameter |Year= ignored (|year= suggested) (help)
  3. ^ "AAPG Research Conference, June 18, 2005, Calgary, Alberta, Canada; #90043 (2005)". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  4. ^ a Template:Journal reference Article link
  5. ^ Template:Journal reference Article link
  6. ^ Kitchka, A., Juvenile Petroleum Pathway: From Fluid Inclusions via Tectonic Pathways to Oil Fields. AAPG Research Conference, Calgary, Canada, 2005. Article link
  7. ^ Template:Journal reference "A Cool Early Earth". Zircons Are Forever. April 11. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  8. ^ Template:Journal reference doi:10.1038/415312a
  9. ^ Szatmari1, P, Da Fonseca, T, and Miekeley, N. Trace Element Evidence for Major Contribution to Commercial Oils by Serpentinizing Mantle Peridotites. AAPG Research Conference, Calgary, Canada, 2005.Article link
  10. ^ "The Prohibition of Hydrocarbon Genesis at Low Pressures". Gas Resources Corporation. April 15. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  11. ^ "http://www.searchanddiscovery.com/documents/abstracts/2005research_calgary/abstracts/short/charlou.htm". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help); External link in |title= (help)
  12. ^ Template:Journal reference
  13. ^ Template:Journal reference
  14. ^ "Hydrothermal Hydrocarbons, by Stanley B. Keith and Monte M. Swan; #90043 (2005)". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  15. ^ Template:Journal reference issue Article link
  16. ^ "Petroleum: To Be Or Not To Be Abiogenic, by M. R. Mello and J. M. Moldowan; #90043 (2005)". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  17. ^ "Joe Vialls, Private Investigator, Exposing Media Disinformation". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  18. ^ "Gas Resources Corporation". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)
  19. ^ "AAPG Research Conference, June 18, 2005, Calgary, Alberta, Canada; #90043 (2005) (See above)". September 9. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)