Data Table of Hydrocarbon Potential for the 1002 AreaReportSummaryProbabilistic Hydrocarbon Potential EstimatesBillion barrels of OilTrillion ft^3 of Gas5%50%95%5%50%95%Hydrocarbon Value for the 1002 AreaReportSummaryProbabilistic Hydrocarbon Potential EstimatesBillion barrels of OilTrillion ft^3 of Gas5%50%95%5%50%95%Team 1 Hydrocarbon Potential Evaluation Team Summary of Knowledge(With respect to ANWR & theDefinition of an A)Summary of Knowledge (wrtANWR&defA) Team 1 November 12, 2003IntroductionThis document serves as a summarization of the research that Team 1 has done regarding its task of determining the ‘potential’ of ANWR with respect to hydrocarbons. Team 1 took it upon itself to determine both the estimated volume of hydrocarbons in ANWR, and the value of these hydrocarbons in the global market. The results you will see here include the following:- Formation of Hydrocarbons- Geologic History- Hydrocarbon Reservoirs- Value of Hydrocarbons- Sources usedEnjoy!-Team 1- -2Summary of Knowledge (wrtANWR&defA) Team 1 November 12, 2003Formation of Hydrocarbons Formation of HydrocarbonsInformation from Petroleum Geology for Geophysicists and Engineers by Richard SelleyFive Major Types of HydrocarbonsKerogen- Kerogen is a fine-grained, amorphous organic matter. It is not soluble to normal petroleum solvents, like carbon disulfide. Its chemical compositioin is 75% C, 10% H, 15% other (sulfur, oxygen, nitrogen, etc.). It is very important in the formation ofhydrocarbons because it is what generates oil and gas. Source rocks must contain significant amounts of kerogen.Asphalt- Asphalt is a solid at surface temperatures. It is soluble to petroleum solvents. It is produced by the partial maturation of kerogen or the degradation of crude oil.Crude Oil- Crude oil is a liquid at surface temperatures. It is soluble to normal petroleumsolvents. It has four main groups of organic compounds: paraffin, naphthalene, aromatics,and resins. Natural Gas- Is a hydrocarbon gas. The major natural gases are methane, ethane, propane, and butane.Condensates-These are hydrocarbons transitional between gas and crude oil.Five Parameters for Hydrocarbon Accumulation1. Source rocks are required to generate hydrocarbons. Generally, has greater than .5% organic matter (kerogen) by weight.2. Reservoir rocks are required to store hydrocarbons.3. Seal or cap rocks are present to prevent the upward escape of hydrocarbons from reservoir.4. Traps occur where the source, reservoir and seal are arranged in a way that the hydrocarbons can move from the source to the reservoir.5. Source rock must have been heated sufficiently for oil (greater than 60ºC) and gas(greater than 150ºC)Three Phases of Alteration of Organic MatterDiagenesis- Diagenesis occurs at the surface at normal temperatures. The organic matter goes under bacterial decay, oxidation, dehydration and decarboxylation. The resultant is kerogen. The porosity decreases 60% to 40%.- -3Summary of Knowledge (wrtANWR&defA) Team 1 November 12, 2003Catagenesis- Temperatures increase to 250ºC and kerogen generates oil or gas. The porosity decreases to 10%.Metagenesis- Occurs at 250ºC right when the kerogen is going to change into oil or gas.Catagenesis is the most important stage, and is different for the three different types of kerogen.Three Types of KerogenType I (Algal)- It is very rich in hydrogen, low in oxygen and contains lipids. It generates oil and is present in oil shales.Type II (Liptinic)- It is made from algal detritus, phytoplankton and zooplankton. It has aliphatic compounds and more hydrogen than carbon. It can generate oil or gas.Type III (Humic)- It has more carbon than hydrogen, and is rich in aromatic compounds.It is produced form lignin in higher woody plants. It generates gas.Type I and Type II are usually found in marine environment and Type III is found in continental environments. That is why there is the generalization that marine produces oiland continental produces gas.Migration of HydrocarbonsPrimary migration of hydrocarbons is the movement of oil and gas from source rock to permeable carrier beds. Secondary migration is the movement from permeable carrier beds to the reservoir beds. Secondary migration occurs through porous rocks due to buoyancy and capillary and regional pressure gradients.- -4Summary of Knowledge (wrtANWR&defA) Team 1 November 12, 2003The Geologic History of ANWRThe purpose of this section is to provide everyone with a basic understanding of how ANWR came about, geologically speaking. This information is important in understanding why hydrocarbons are where they are, and is also important in understanding its current geological condition (such as seismic activity, how that impacts exploitation, and so forth). The information is very brief, and the sources used are at the conclusion. Geographic PlacementThe 1002 area of the Arctic National Wildlife Refuge is a 1.5-million-acre area innortheastern Alaska. It is bounded on the east by the Canning and Staines Rivers, on thenorth by the Beaufort Sea, on the east by the Aichilik River and the Canadian border, andto the south by Brooks Range, and is roughly 105 miles east-west and 16-40 miles north-south.Most of the 1002 area lies within the Arctic Coastal Plain physiographic province, amarshy area that slopes gradually towards the Arctic Ocean on the north. A small partalong the southern margin that constitutes less than 5% of the total area lies within theArctic Foothills physiographic province, a series of hills and ridges that descend frommore than 500 m in the Brooks Range to 300 m in elevation to the northern foreland. Thearea is treeless, tundra covered, and 99% wetland. Topographically speaking, it is comprised of foothills (95% of area), river flooded plains(25%), hilly coastal plains (22%), lagoons and oceans (5%), thaw lake plains (5%) andmountains (less than 1%). It also has beaches, low steep cliffs, barrier islands, shallowlagoons, and river deltas form the coast of the 1002 area, with hills rising to more than300 m in the south. Many rivers and stream flow between these hills towards the ArcticOcean.HistoryThe geologic history of ANWR is briefly as follows:- "Development of Devonian to Triassic south-facing (in present-day coordinates) passive continental margin."- "Northern Part- margin rifted in Jurassic to early cretaceous time for an unknown parent continent"- "Coeval with the North, and arc-continent collision
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