PETROLEUM INDUSTRY

PETROLEUM  INDUSTRY

Ø PETROLEUM (Mineral Oil, Crude Oil):

                                      Petroleum is a naturally occurring, smelly, yellow-to-black liquid consisting of a complex mixture of hydrocarbons of various molecular weights and other liquid organic compounds  that are found in geologic formations beneath the Earth's surface. The name Petroleum covers both naturally occurring unprocessed crude oils and petroleum products that are made up of refined crude oil.  A fossil fuel, it is formed when large quantities of dead organisms, usually zooplankton and algae, are buried underneath sedimentary rock and undergo intense heat and pressure.

                                Mineral or crude oil is formed by slow chemical and biological decomposition of remains of organic matter (plants and animals) found between the sedimentary rocks. Mineral or crude oil appears like a liquid of blackish colour. Mineral oil is called “PETROLEUM” when it is in refined form. Petroleum on fractional distillation gives different fraction.

Ø HISTORY:

·      NATURAL HISTORY:

                             Petroleum is a naturally occurring liquid found in rock formations. It consists of a complex mixture of hydrocarbons of various molecular weights, plus other organic compounds. It is generally accepted that oil is formed mostly from the carbon rich remains of ancient plankton after exposure to heat and pressure in the Earth's crust over hundreds of millions of years. Over time, the decayed residue was covered by layers of mud and silt, sinking further down into the Earth’s crust and preserved there between hot and pressured layers, gradually transforming into oil reservoires.

Ø EARLY HISTORY:

                          Petroleum in an unrefined state has been utilized by humans for over 5000 years. Oil in general has been used since early human history to keep fires ablaze, and also for warfare.

                      Its importance in the world economy evolved slowly, with whale oil used for lighting into the 19th century and wood and coal used for heating and cooking well into the 20th Century. The Industrial Revolution generated an increasing need for energy which was fueled mainly by coal, with other sources including whale oil. However, it was discovered that kerosene could be extracted from crude oil and used as a light and heating fuel. Petroleum was in great demand, and by the twentieth century had become the most valuable commodity traded on the world markets

Ø MODERN HISTORY:

                        The first modern oil refineries were built by Ignacy Łukasiewicz near Jasło. The first modern oil refineries were built by Ignacy Łukasiewicz near Jasło

                        The first commercial oil well in Canada became operational in 1858 at Oil Springs, Ontario (then Canada West). Businessman James Miller Williams dug several wells between 1855 and 1858 before discovering a rich reserve of oil four metres below ground. The discovery at Oil Springs touched off an oil boom which brought hundreds of speculators and workers to the area.

                     After World War II ended, the countries of the Middle East took the lead in oil production from the United States. Important developments since World War II include deep-water drilling, the introduction of the Drillship, and the growth of a global shipping network for petroleum relying upon oil tankers and pipelines. In the 1960s and 1970s, multi-governmental organizations of oil–producing nations OPEC and OAPEC played a major role in setting petroleum prices and policy. Oil Spills and their cleanup have become an issue of increasing political, environmental, and economic importance.

Ø COMPOSITION:

                    Petroleum includes only crude oil, but in common usage it includes all liquid, gaseous, and solid hydrocarbons. Under surface pressure and temperature conditions, lighter hydrocarbons methane, ethane, propane and butane occur as gases, while pentane and heavier ones are in the form of liquids or solids. However, in an underground oil reservoir the proportions of gas, liquid, and solid depend on subsurface conditions and on the phase diagram of the petroleum mixture.

                 An oil well produces predominantly crude oil, with some natural gas dissolved in it. Because the pressure is lower at the surface than underground, some of the gas will come out of solution and be recovered (or burned) as associated gas or solution gas. A gas well produces predominantly natural gas. However, because the underground temperature and pressure are higher than at the surface, the gas may contain heavier hydrocarbons such as pentane, hexane, and heptane in the gaseous state.

                  The proportion of light hydrocarbons in the petroleum mixture varies greatly among different oil fields, ranging from as much as 97 percent by weight in the lighter oils to as little as 50 percent in the heavier oils and bitumens.

                The hydrocarbons in crude oil are mostly alkanes, cycloalkanes and various aromatic hydrocarbons while the other organic compounds contain nitrogen, oxygen and sulfur, and trace amounts of metals such as iron, nickel, copper and vanadium. The exact molecular composition varies widely from formation to formation but the proportion  of chemical elements  vary over fairly narrow limits as follows:

Composition by weight

Element	Percent range
Carbon	83 to 85%
Hydrogen	10 to 14%
Nitrogen	0.1 to 2%
Oxygen	0.05 to 1.5%
Sulfur	0.05 to 6.0%
Metals	< 0.1%

Four different types of hydrocarbon molecules appear in crude oil. The relative percentage of each varies from oil to oil, determining the properties of each oil.

Composition by weight

Hydrocarbon	Average	Range
Alkanes (paraffins)	30%	15 to 60%
Naphthenes	49%	30 to 60%
Aromatics	15%	3 to 30%
Asphaltics	6%	remainder

Ø CHEMISTRY:

                   Petroleum is a mixture of a very large number of different hydrocarbons; the most commonly found molecules are alkanes (paraffins), cycloalkanes (naphthenes), aromatic hydrocarbons, or more complicated chemicals like asphaltenes. Each petroleum variety has a unique mix of molecules, which define its physical and chemical properties, like color and viscosity.

Ø FORMATION:

                   Petroleum is a fossil fuel derived from ancient fossilized organic materials, such as zooplankton and algae. Vast quantities of these remains settled to sea or lake bottoms, mixing with sediments and being buried under anoxic conditions.  As further layers settled to the sea or lake bed, intense heat and pressure built up in the lower regions. This process caused the organic matter to change, first into a waxy material known as kerogen, which is found in various oil shales around the world, and then with more heat into liquid and gaseous hydrocarbons via a process known as catagenesis. Formation of petroleum occurs from hydrocarbon pyrolysis in a variety of mainly endothermic reactions at high temperature and/or pressure.

                 Geologists often refer to the temperature range in which oil forms as an "oil window"—below the minimum temperature oil remains trapped in the form of kerogen, and above the maximum temperature the oil is converted to natural gas through the process of thermal cracking. Sometimes, oil formed at extreme depths may migrate and become trapped at a much shallower level.

Structure of a vanadium porphyrin compound (left) extracted from petroleum by Alfred E. Treibs, father of organic geochemistry. Treibs noted the close structural similarity of this molecule and chlorophyll.

Ø PETROLEUM INDUSTRY:

                 Petroleum industry includes the global processes of exploration, extraction, refining, transporting (often by oil tankers and pipelines), and marketing petroleum products. The largest volume products of the industry are fuel oil and gasoline (petrol). Petroleum is also the raw material for many chemical products, including pharmaceuticals, solvents, fertilizers, pesticides, and plastics. The industry is usually divided into three major components: upstream, midstream and downstream. Midstream operations are usually included in the downstream category.

Ø Upstream:

              The upstream oil sector is a term commonly used to refer to the exploration, development and production for and the recovery and production of crude oil and natural gas. The upstream oil sector is also known as the exploration and production (E&P) sector. The upstream sector includes the exploration for potential underground or underwater oil and gas fields, drilling of exploratory wells, and subsequently operating the wells that recover and bring the crude oil and/or raw natural gas to the surface.

Ø Midstream:

            The midstream industry processes, stores, markets and transports commodities such as crude oil, natural gas, natural gas liquids (LNGs, mainly ethane, propane and butane) and sulphur. Midstream operations and processes include the following:

·        Gathering:   The gathering process employs narrow, low-pressure pipelines to connect oil- and gas-producing wells to larger, long-haul pipelines or processing facilities.

·       Processing/refining:   Processing and refining operations turn crude oil and gas into marketable products. In the case of crude oil, these products include heating oil, gasoline for use in vehicles, jet fuel, and diesel oil. Oil refining processes include distillation, vacuum distillation, catalytic reforming, catalytic cracking, alkylation, isomerization and hydrotreating. Natural gas processing includes compression; glycol dehydration; amine treating; separating the product into pipeline-quality natural gas and a stream of mixed natural gas liquids; and fractionation, which separates the stream of mixed natural gas liquids into its components. The fractionation process yields ethane, propane, butane, isobutane, and natural gasoline.

·        Transportation:   Oil and gas are transported to processing facilities, and from there to end users, by pipeline, tanker/barge, truck, and rail. Pipelines are the most economical transportation method and are most suited to movement across longer distances, for example, across continents. Tankers and barges are also employed for long-distance, often international transport. Rail and truck can also be used for longer distances but are most cost-effective for shorter routes.

·       Storage:    Midstream service providers provide storage facilities at terminals throughout the oil and gas distribution systems. These facilities are most often located near refining and processing facilities and are connected to pipeline systems to facilitate shipment when product demand must be met. While petroleum products are held in storage tanks, natural gas tends to be stored in underground facilities, such as salt dome caverns and depleted reservoirs. Technological applications: Midstream service providers apply technological solutions to improve efficiency during midstream processes. Technology can be used during compression of fuels to ease flow through pipelines; to better detect leaks in pipelines; and to automate communications for better pipeline and equipment monitoring.

Ø Downstream:

                       The downstream oil sector is a term commonly used to refer to the refining of crude oil, and the selling and distribution of natural gas and products derived from crude oil. Such products include liquified petroleum gas (LPG), gasoline or petrol, jet fuel, diesel oil, other fuel oils, asphalt and petroleum coke. The downstream sector includes oil tankers, oil refineries, petrochemical plants, petroleum products & their distribution, retailers & retail outlets and natural gas distribution companies. The downstream industry includes consumers through thousands of refined petroleum products such as oil, diesel, jet fuel, heating oil, asphalt, lubricants, synthetic rubber, plastics, fertilizers, antifreeze, pesticides, pharmaceuticals, natural gas and propane.

Ø EXPLORATION OF PETROLEUM:

Hydrocarbon exploration (or oil and gas exploration) is the search by petroleum geologists and geophysicists for hydrocarbon deposits beneath the Earth's surface, such as oil and natural gas. Oil and gas exploration are grouped under the science of petroleum geology.

·       Exploration methods:

                      Visible surface features such as oil seeps, natural gas seeps, pockmarks (underwater craters caused by escaping gas) provide basic evidence of hydrocarbon generation (be it shallow or deep in the Earth). However, most exploration depends on highly sophisticated technology to detect and determine the extent of these deposits using exploration geophysics. Areas thought to contain hydrocarbons are initially subjected to a gravity survey, magnetic survey, passive seismic or regional seismic reflection surveys to detect large-scale features of the sub-surface geology. Features of interest (known as leads) are subjected to more detailed seismic surveys which work on the principle of the time it takes for reflected sound waves to travel through matter (rock) of varying densities and using the process of depth conversion to create a profile of the substructure. Finally, when a prospect has been identified and evaluated and passes the oil company's selection criteria, an exploration well is drilled in an attempt to conclusively determine the presence or absence of oil or gas.

                   Oil exploration is an expensive, high-risk operation. Offshore and remote area exploration is generally only undertaken by very large corporations or national governments.

·        Exploration risk:

                 Hydrocarbon exploration is a high risk investment and risk assessment is paramount for successful exploration portfolio management. Exploration risk is a difficult concept and is usually defined by assigning confidence to the presence of five imperative geological factors, as discussed above. This confidence is based on data and/or models and is usually mapped on Common Risk Segment Maps (CRS Maps). High confidence in the presence of imperative geological factors is usually colored green and low confidence colored red. Therefore these maps are also called Traffic Light Maps, while the full procedure is often referred to as Play Fairway Analysis. The aim of such procedures is to force the geologist to objectively assess all different geological factors.                           Furthermore it results in simple maps that can be understood by non-geologists and managers to base exploration decisions on.

·       Terms used in petroleum evaluation:

§  Bright spot - On a seismic section, coda that have high amplitudes due to a formation containing hydrocarbons.

§  Dry hole - A boring that does not contain commercial hydrocarbons.

Flat spot - Possibly an oil-water, gas-water or gas-oil contact on a seismic section; flat due to gravity.

Ø RESERVOIRS:

·       CRUDE OIL RESERVOIRS:

              Three conditions must be present for oil reservoirs to form: a source rock rich in hydrocarbon material buried deep enough for subterranean heat to cook it into oil; a porous and permeable reservoir rock for it to accumulate in; and a cap rock (seal) or other mechanism that prevents it from escaping to the surface. Within these reservoirs, fluids will typically organize themselves like a three-layer cake with a layer of water below the oil layer and a layer of gas above it, although the different layers vary in size between reservoirs. Because most hydrocarbons are less dense than rock or water, they often migrate upward through adjacent rock layers until either reaching the surface or becoming trapped within porous rocks (known as reservoirs) by impermeable rocks above. However, the process is influenced by underground water flows, causing oil to migrate hundreds of kilometres horizontally or even short distances downward before becoming trapped in a reservoir. When hydrocarbons are concentrated in a trap, an oil field forms, from which the liquid can be extracted by drilling and pumping.

          The reactions that produce oil and natural gas are often modeled as first order breakdown reactions, where hydrocarbons are broken down to oil and natural gas by a set of parallel reactions, and oil eventually breaks down to natural gas by another set of reactions. The latter set is regularly used in petrochemical plants and oil refineries.

              Wells are drilled into oil reservoirs to extract the crude oil. "Natural lift"   production methods that rely on the natural reservoir pressure to force the oil to the surface are usually sufficient for a while after reservoirs are first tapped. In some reservoirs, such as in the Middle East, the natural pressure is sufficient over a long time. The natural pressure in most reservoirs, however, eventually dissipates. Then the oil must be extracted using "artificial lift" means. Over time, these "primary" methods become less effective and "secondary" production methods may be used. A common secondary method is "waterflood" or injection of water into the reservoir to increase pressure and force the oil to the drilled shaft or "wellbore." Eventually "tertiary" or "enhanced" oil recovery methods may be used to increase the oil's flow characteristics by injecting steam, carbon dioxide and other gases or chemicals into the reservoir. In the United States, primary production methods account for less than 40 percent of the oil produced on a daily basis, secondary methods account for about half, and tertiary recovery the remaining 10 percent. Extracting oil (or "bitumen") from oil/tar sand and oil shale deposits requires mining the sand or shale and heating it in a vessel or retort, or using "in-situ" methods of injecting heated liquids into the deposit and then pumping out the oil-saturated liquid.

Ø Extraction of petroleum:

                 The extraction of petroleum is the process by which usable petroleum is extracted and removed from the earth.

·        Locating the oil field:   Geologists use seismic surveys to search for geological structures that may form oil reservoirs. The "classic" method includes making an underground explosion nearby and observing the seismic response that provides information about the geological structures under the ground. However, "passive" methods that extract information from naturally-occurring seismic waves are also known.

Other instruments such as gravimeters and magnetometers are also sometimes used in the search for petroleum. Extracting crude oil normally starts with drilling wells into the underground reservoir. When an oil well has been tapped, a geologist (known on the rig as the "mudlogger") will note its presence. Such a "mudlogger" is known to be sitting on the rig. Historically, in the USA, some oil fields existed where the oil rose naturally to the surface, but most of these fields have long since been used up, except in certain places in Alaska. Often many wells (called multilateral wells) are drilled into the same reservoir, to ensure that the extraction rate will be economically viable. Also, some wells (secondary wells) may be used to pump water, steam, acids or various gas mixtures into the reservoir to raise or maintain the reservoir pressure, and so maintain an economic extraction rate.

·       Drilling:   Petroleum is recovered mostly through oil drilling. This comes after the studies of structural geology (at the reservoir scale), sedimentary basin analysis, reservoir characterization (mainly in terms of the porosity and permeability of geologic reservoir structures). It is refined and separated, most easily by boiling point, into a large number of consumer products, from gasoline (petrol) and kerosene to asphalt and chemical reagents used to make plastics and pharmaceuticals. Petroleum is used in manufacturing a wide variety of materials, and it is estimated that the world consumes about 90 million barrels each day.

                            The use of fossil fuels such as petroleum can have a negative impact on Earth's biosphere, releasing pollutants and greenhouse gases into the air and damaging ecosystems through events such as oil spills. Concern over the depletion of the earth's finite reserves of oil, and the effect this would have on a society dependent on it, is a concept known as peak oil.

                    The oil well is created by drilling a long hole into the earth with an oil rig.  A steel pipe (casing) is placed in the hole, to provide structural integrity to the newly drilled well bore. Holes are then made in the base of the well to enable oil to pass into the bore. Finally a collection of valves called a "Christmas Tree" is fitted to the top, the valves regulating pressures and controlling flows.

Ø OIL REFINERY:

                  An oil refinery or petroleum refinery is an industrial process plant where crude oil is processed and refined into more useful products such as petroleum naphtha, gasoline, diesel fuel, asphalt base, heating oil, kerosene and liquefied petroleum gas. Oil refineries are typically large, sprawling industrial complexes with extensive piping running throughout, carrying streams of fluids between large chemical processing units. In many ways, oil refineries use much of the technology of, and can be thought of, as types of chemical plants. The crude oil feedstock has typically been processed by an oil production plant. There is usually an oil depot (tank farm) at or near an oil refinery for the storage of incoming crude oil feedstock as well as bulk liquid products. An oil refinery is considered an essential part of the downstream side of the petroleum industry.

·        OPERATION:   Raw or unprocessed crude oil is not generally useful in industrial applications, although "light, sweet" (low viscosity, low sulfur) crude oil has been used directly as a burner fuel to produce steam for the propulsion of seagoing vessels. The lighter elements, however, form explosive vapors in the fuel tanks and are therefore hazardous, especially in warships. Instead, the hundreds of different hydrocarbon molecules in crude oil are separated in a refinery into components which can be used as fuels, lubricants, and as feedstocks in petrochemical processes that manufacture such products as plastics, detergents, solvents, elastomers and fibers such as nylon and polyesters.

                                                  Petroleum fossil fuels are burned in internal combustion engines to provide power for ships, automobiles, aircraft engines, lawn mowers, chainsaws, and other machines. Different boiling points allow the hydrocarbons to be separated by distillation. Since the lighter liquid products are in great demand for use in internal combustion engines, a modern refinery will convert heavy hydrocarbons and lighter gaseous elements into these higher value products.

Crude oil is separated into fractions by fractional distillation. The fractions at the top of the fractionating column have lower boiling points than the fractions at the bottom. The heavy bottom fractions are often cracked into lighter, more useful products. All of the fractions are processed further in other refining unit.

Ø OIL REFINERIES IN PAKISTAN:

There are four oil refineries in Pakistan.

       I.            Attock oil refinery located at Morgah near Rawalpindi has 1.25 million tones of oil refinery capacity.

    II.            Two oil refinery located at Karachi having 2.13 million tones of oil refinery capacity.

 III.            Pak Arab Oil Refinery is located at Mehmud kot near Multan.

Ø CRACKING OF PETROLEUM:

                                 The breakdown of higher hydrocarbons having high boiling points into variety of lower hydrocarbon which are more volatile and have low boiling points is called “Cracking”.

·       IMPORTANCE OF CRACKING:

                              The fractional distillation  of  petroleum gives only 20% gasoline. This amount cannot meet its high demand since it is used as motor fuel. The supply of gasoline is increased by cracking the surplus amount of less wanted petroleum fractions like kerosene and gas oil.

·        Example:

                     C₁₄H₃₄ +C₇H₁₆ + CH₃−CH=CH₂ + CH₂=CH₂

                    The product formation depends upon the condition under which cracking takes place.

·        TYPES OF CRACKING:

                            Cracking process is generally carried out in following ways.

1.     THERMAL CRACKING :

                     A type of  cracking in which large hydrocarbons are broken down into smaller ones in the presence of high temperature and pressure.

                   In thermal cracking, high temperatures (typically in the range of 450°C to 750°C) and pressures (up to about 70 atmospheres) are used to break the large hydrocarbons into smaller ones. Thermal cracking gives mixtures of products containing high proportions of hydrocarbons with double bonds - alkenes.

2.     CATALYTIC CRACKING:

            Modern cracking uses zeolites as the catalyst. These are complex aluminosilicates, and are large lattices of aluminium, silicon and oxygen atoms carrying a negative charge. They are, of course, associated with positive ions such as sodium ions. You may have come across a zeolite if you know about ion exchange resins used in water softeners.

The alkane is brought into contact with the catalyst at a temperature of about 500°C and moderately low pressures.

The zeolites used in catalytic cracking are chosen to give high percentages of hydrocarbons with between 5 and 10 carbon atoms - particularly useful for petrol (gasoline). It also produces high proportions of branched alkanes and aromatic hydrocarbons like benzene.

3.   STEAM CRACKING:

             Steam cracking is a petrochemical process in which saturated hydrocarbons are broken down into smaller, often unsaturated, hydrocarbons. It is the principal industrial method for producing the lighter alkenes (or commonly olefins), including ethene (or ethylene) and propene (or propylene).

              In steam cracking, a gaseous or liquid hydrocarbon feed like naphtha, LPG or ethane is diluted with steam and briefly heated in a furnace without the presence of oxygen. Typically, the reaction temperature is very high, at around 850°C.

Ø REFORMING OF PETROLEUM:

                        The conversion of straight chain hydrocarbon into branched chain hydrocarbon is called reforming of petroleum. By the process of reforming, the octane number of a gasoline is improved. The process of reforming is carried out in the presence of catalyst n-alkanes burn in internal combustion engine with explosion and produce knocking but branched chain hydrocarbons burn smoothly.  Reforming is a process similar to cracking, which converts n-alkanes into branched alkanes.

                      The octane number of gasoline may also be improved by adding tetraethyl lead (TEL) Pb(C₂H₅)₄ which is a knock inhibitor. But  the use of compounds containing lead cause environment pollution.

·       KNOCKING:

                 Knocking is a sharp metallic sound produced in the internal combustion engine. Knocking is caused by the low octane number of gasoline.

·       GASOLINE:

               Gasoline which is commonly known as petrol is a mixture of n-hexane and n-heptane. During the process of fractional distillation, it is obtained in the upper most portion of the tower.

·       OCTANE NUMBER:

              Octane number is a standard which determines the knocking ability and quality of gasoline. Higher is the octane number of a gasoline, lower is the knocking it produces.

 Octane number can be increased by the following two methods:

 Reforming

 By adding TEL (tetraethyl lead)

Ø USES OF PETROLEUM:

                   The chemical structure of petroleum is heterogeneous, composed of hydrocarbon chains of different lengths. Because of this, petroleum may be taken to oil refineries and the hydrocarbon chemicals separated by distillation and treated by other chemical processes, to be used for a variety of purposes.

·        BUNKER FUEL:   Bunker fuel, which is also know as heavy oil, is used to power ships. It typically contains a high number of pollutants and contaminants. Use is increasing with the shipping associated with global commerce.

·        DETERGENT:    All soapless detergents used to wash clothes and dishes are derived from the petrochemical glycerin.

·        PLASTICS:   All plastic, unless it is “bioplastic”, is made from petrochemicals. Every product made from or containing plastic is a product that exists only through the distillation of petroleum.

·        JET FUEL:   The standard type of jet fuel, Jet A, is a petroleum product with a number of additives to prevent sparking, gumming, corrosion, and icing.

·        DIESEL FUEL:   Diesel, unless it is “biodiesel”, is made from refining crude oil. It is generally used in medium- and heavy-duty vehicles requiring a great deal of power and torque, like garbage trucks, road equipment, buses, and trains.

·        HEATING OIL:   Heating oil is a petroleum product used to fuel furnaces or boilers. In the U.S., most heating oil is consumed in the northeast.

·        PAINT :   Plastic and oil based paints, as well as paint additives, are manufactured from petrochemicals.

·        GASOLINE:    Gasoline is the most commonly used product by Americans for their day to day transportation needs. 45% of all oil used in the U.S. goes to gasoline, which means we consume in excess of 180 million gallons of gasoline a day.

Ø ENVIRONMENTAL EFFECTS:

                       Because petroleum is a naturally occurring substance, its presence in the environment need not be the result of human causes such as accidents and routine activities (seismic exploration, drilling, extraction, refining and combustion). Phenomena such as seeps and tar pits are examples of areas that petroleum affects without man's involvement. Regardless of source, petroleum's effects when released into the environment are similar.

Ø GLOBAL WARMING:

                     When burned, petroleum releases carbon dioxide; a greenhouse gas. Along with the burning of coal, petroleum combustion is the largest contributor to the increase in atmospheric CO₂. Atmospheric CO₂ has risen steadily since the industrial revolution to current levels of over 390 ppmv, from the 180 – 300 ppmv of the prior 800 thousand years, driving global warming. The unbridled use of petroleum could potentially cause a runaway greenhouse effect on Earth.[citation needed] Use of oil as an energy source has caused Earth's temperature to increase by nearly one degree Celsius. This raise in temperature has reduced the Arctic ice cap to 1,100,000 sq mi (2,800,000 km²), smaller than ever recorded. Because of this melt, more oil reserves have been revealed. It is estimated by the International Energy Agency that about 13 percent of the world's undiscovered oil resides in the Arctic.  

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