Instruct: Given a question, retrieve relevant documents that can help answer the question.
Query: How much does oil shale sell for?
The production cost of a barrel of shale oil ranges from as high as US$95 per barrel to as low US$25 per barrel, although there is no recent confirmation of the latter figure.[4] The industry is proceeding cautiously, due to the losses incurred during the last major investment into oil shale in the early 1980s, when a subsequent collapse in the oil price left the projects uneconomical.[5]
The United States has the largest known deposits of oil shale in the world, according to the Bureau of Land Management and holds an estimated of potentially recoverable oil. Oil shale does not actually contain oil, but a waxy oil precursor known as kerogen. There is no significant commercial production of oil from oil shale in the United States.
Phosphoria Formation is made up of Permian Shales. It is believed that the organic rich shales are the primary source to much of the oil in the region. It is thought that the oil from these shales have migrated into the Pennsylvanian Tensleep Formation, and Paleozoic reservoirs of Central and Eastern Wyoming. Due to its carbonate and chert rich depositional environment, the oil found in the Phosphoria Formation as a high sulfer content making it Type-IIS kerogen. This is important to note because sulfur rich oils have been known to mature at much lower temperatures than normal. The Tensleep Formation is the most prominent reservoir rock hosting approximately 142 million barrels of oil with about 12 fields producing from this unit. The Phosphoria Formation was sealed by the marine shale units of the Triassic Dinwoody Formation. This shale seal was broken during the Laramide Orogeny leading to the migration of oil into the Tensleep Formation. The oil now is trapped in anticlines formed by the Laramide. 
Though similar in their formation process, oil shales differ from coals in several distinct ways. The precursors of the organic matter in oil shale and coal differ in a sense that oil shale is of algal origin, but may also include remains of vascular land plants that more commonly compose much of the organic matter in coal. The origin of some of the organic matter in oil shale is obscure because of the lack of recognizable biologic structures that would help identify the precursor organisms. Such materials may be of bacterial origin or the product of bacterial degradation of algae or other organic matter.
Oil shale differs from bitumen-impregnated rocks (oil sands and petroleum reservoir rocks), humic coals and carbonaceous shale. While oil sands do originate from the biodegradation of oil, heat and pressure have not (yet) transformed the kerogen in oil shale into petroleum, that means that its maturation does not exceed early mesocatagenetic.[13][14][15]
The shale oil derived from oil shale does not directly substitute for crude oil in all applications. It may contain higher concentrations of olefins, oxygen, and nitrogen than conventional crude oil.[41] Some shale oils may have higher sulfur or arsenic content. By comparison with West Texas Intermediate, the benchmark standard for crude oil in the futures-contract market, the Green River shale oil sulfur content ranges from near 0% to 4.9% (in average 0.76%), where West Texas Intermediate's sulfur content has a maximum of 0.42%.[62] The sulfur content in shale oil from Jordan's oil shales may rise even up to 9.5%.[63] The arsenic content, for example, becomes an issue for Green River formation oil shale. The higher concentrations of these materials means that the oil must undergo considerable upgrading (hydrotreating) before serving as oil-refinery feedstock.[64] Above-ground retorting processes tended to yield a lower API gravity shale oil than the in situ processes. Shale oil serves best for producing middle-distillates such as kerosene, jet fuel, and diesel fuel. Worldwide demand for these middle distillates, particularly for diesel fuels, increased rapidly in the 1990s and 2000s.[41][65] However, appropriate refining processes equivalent to hydrocracking can transform shale oil into a lighter-range hydrocarbon (gasoline).[41]
Oil shale gas is produced by retorting (pyrolysis) of oil shale. In the pyrolysis process, oil shale is heated until its kerogen decomposes into vapors of a petroleum-like condensable shale oil, non-condensible combustible oil shale gas, and spent shale—a solid residue. The process is the same as the shale oil extraction and oil shale gas usually occurs as a byproduct of shale oil production. The ratio of oil shale gas to shale oil depends on retorting temperature and as a rule, increases by the rise of temperature.
The biggest oil shale reserves in Europe are located in Russia (equal to 35.47 billion metric tons of shale oil). Major deposits are located in the Volga-Petchyorsk province and in the Baltic Oil Shale Basin. Other major oil shale deposits in Europe are located in Italy (10.45 billion metric tons of shale oil), Estonia (2.49 billion metric tons of shale oil), France (1 billion metric tons of shale oil), Belarus (1 billion metric tons of shale oil), Sweden (875 million metric tons of shale oil), Ukraine (600 million metric tons of shale oil) and the United Kingdom (500 million metric tons of shale oil). There are oil shale reserves also in Germany, Luxembourg, Spain, Bulgaria, Hungary, Poland, Serbia, Austria, Albania, and Romania.
As a heat carrier, LLNL HRS process uses spent oil shale. Raw oil shale and spent oil shale are mixed in the fluidized bed mixer. The use of fluidized bed mixer results in better mixture, which in turn increases the mean quantity of oil yield and oil shale throughput. From the fluidized bed mixer oil shale moves downward to the packed-bed pyrolyzer. The heat is transferred from the heated spent oil shale to the raw oil shale causing pyrolysis. As a result, oil shale decomposes to shale oil vapors, oil shale gas and spent oil shale. Oil vapors are collected from the pyrolyzer. The spent oil shale, still including residual carbon (char), by the air pneumatic lift pipe to the delayed-fall combustor where it is combusted to heat the process. The delayed-fall combustor used in this process gives greater control over the combustion process as compared to a lift pipe combustor. From the delayed-fall combustor the oil shale ash and spent shale falls into a fluidized bed classifier where the finest parts of solids are removed and hot spent shale is forwarded to the fluidized bed mixer.
Lower temperature and pressure during the diagenesis process compared to other modes of hydrocarbon generation result in a lower maturation level of oil shale. Continuous burial and further heating and increased pressure over time could result in the conventional production of oil and gas from the oil shale source rock. The largest deposits are found in the remains of large lakes such as the deposits of the Green River Formation of Wyoming and Utah, USA. Large lake oil shale basins are typically found in areas of block faulting or crustal warping due to mountain building. Deposits such as the Green River may be as much as and yield up to 40 gallons of oil for each ton (166 l/t) of shale.
Eesti Energia produces and sells electricity, heat and fuel (oil shale and shale oil) and provides customer and consulting services. The company is engaged in the oil shale mining through its subsidiary Enefit Kaevandused, which extracts oil shale by opencast mining in the Narva quarry and by underground mining in the Estonia mine.
The Lurgi–Ruhrgas process is a hot recycled solids technology, which processes fine particles of coal or oil shale sized . As a heat carrier, it uses spent char or spent oil shale (oil shale ash), mixed with sand or other more durable materials. In this process, crushed coal or oil shale is fed into the top of the retort. In retort, coal or oil shale is mixed with the heated char or spent oil shale particles in the mechanical mixer (screw conveyor). The heat is transferred from the heated char or spent oil shale to the coal or raw oil shale causing pyrolysis. As a result, oil shale decomposes to shale oil vapors, oil shale gas and spent oil shale. The oil vapor and product gases pass through a hot cyclone for cleaning before sending to a condenser. In the condenser, shale oil is separated from product gases.
Oil shale deposits formed in the shallow seas of continental shelves generally are much thinner than large lake basin deposits. These are typically a few meters thick and are spread over very large areas, extending up to thousands of square kilometers. Of the three lithologic types of oil shales, siliceous oil shales are most commonly found in such environments. These oil shales are not as organically rich as lake-deposited oil shales, and generally do not contain more than 30 gallons of extractable oil per ton of oil shale. Oil shales deposited in lagoonal or small lake environments are rarely extensive and are often associated with coal-bearing rocks. These oil shales can have high yields– as much as 40 gallons per ton (166 l/t) of oil shale. However, due to their small areal extent, they are considered unlikely candidates for commercial exploitation.
Northeastern Estonia and the Narva region in particular was the site of an oil-shale industry which provided electricity and heat. Estonia was the only nation to have ever had an oil-shale based energy system. Mining for oil-shale caused Estonia to have the highest amounts of pollution in the Baltic States. Surrounding nations pressured Estonia to reduce its emissions, but a lack of desulfurization equipment has forced Estonia to instead lower its energy production, which has hurt the nation economically. Water pollution has also been considered among the worst of Estonia’s environmental problems because it does not have the infrastructure to effectively treat as much sewage as is created.
Tight oil (also known as shale oil, shale-hosted oil or light tight oil, abbreviated LTO) is light crude oil contained in petroleum-bearing formations of low permeability, often shale or tight sandstone. Economic production from tight oil formations requires the same hydraulic fracturing and often uses the same horizontal well technology used in the production of shale gas. While sometimes called "shale oil", tight oil should not be confused with oil shale, which is shale rich in kerogen, or shale oil, which is oil produced from oil shales. Therefore, the International Energy Agency recommends using the term "light tight oil" for oil produced from shales or other very low permeability formations, while the World Energy Resources 2013 report by the World Energy Council uses the terms "tight oil" and "shale-hosted oil".
Oil shale formation takes place in a number of depositional settings and has considerable compositional variation. Oil shales can be classified by their composition (carbonate minerals such as calcite or detrital minerals such as quartz and clays) or by their depositional environment (large lakes, shallow marine, and lagoon/small lake settings). Much of the organic matter in oil shale is of algal origin, but may also include remains of vascular land plants. Three major type of organic matter (macerals) in oil shale are telalginite, lamalginite, and bituminite. Some oil-shale deposits also contain metals which include vanadium, zinc, copper, and uranium.
Oil shale geology is a branch of geologic sciences which studies the formation and composition of oil shales–fine-grained sedimentary rocks containing significant amounts of kerogen, and belonging to the group of sapropel fuels. Oil shale formation takes place in a number of depositional settings and has considerable compositional variation. Oil shales can be classified by their composition (carbonate minerals such as calcite or detrital minerals such as quartz and clays) or by their depositional environment (large lakes, shallow marine, and lagoon/small lake settings). Much of the organic matter in oil shales is of algal origin, but may also include remains of vascular land plants. Three major type of organic matter (macerals) in oil shale are telalginite, lamalginite, and bituminite. Some oil shale deposits also contain metals which include vanadium, zinc, copper, and uranium.
The second category of eastern oil-shale resources are the Paleozoic black shales, of lower oil yield, but of much larger size than the cannel coals. Most attention has been given to the shales near the Devonian/Mississippian boundary, which are variously called the Ohio Shale, Chattanooga Shale, the Antrim Shale, and the New Albany Shale.
There are a wide variety of extraction methods, which yield significantly different quantities of useful oil. As a result, the estimated amounts of resources and reserves display wide variance. The kerogen content of oil shale formations differs widely, and the economic feasibility of its extraction is highly dependent on international and local costs of oil. Several methods are used to determine the quantity and quality of the products extracted from shale oil. At their best, these methods give an approximate value to its energy potential. One standard method is the Fischer Assay, which yields a heating value, that is, a measure of caloric output. This is generally considered a good overall measure of usefulness. The Fischer Assay has been modified, standardized, and adapted by the American Petroleum Institute. It does not, however, indicate how much oil could be extracted from the sample. Some processing methods yield considerably more useful product than the Fischer Assay would indicate. The Tosco II method yields over 100% more oil, and the Hytort process yields between 300% to 400% more oil.
Some 2011 studies pointed to high rates of decline of some shale gas wells as an indication that shale gas production may ultimately be much lower than is currently projected. But shale-gas discoveries are also opening up substantial new resources of tight oil / "shale oil".
The oil shale that underlies almost in the eastern United States was formed in a marine depositional environment, very different from the Green River Basins. These deposits have also undergone commercialization attempts; they are also resources for natural gas and have been mined for low-grade oil shale. These oil shales were formed during the Late Devonian and Early Mississippian periods. During this time, much of the eastern United States was covered by a large shallow sea. The oil shale is thought to have been the result of slow deposition of planktonic algae. under anoxic conditions. In parts of the basin close to the shoreline, the organic mixture that helped form the oil shale contains organic-rich sediment from the rising Appalachian mountains.
Oil shale belongs to the group of sapropel fuels. It does not have a definite geological definition nor a specific chemical formula, and its seams do not always have discrete boundaries. Oil shales vary considerably in their mineral content, chemical composition, age, type of kerogen, and depositional history and not all oil shales would necessarily be classified as shales in the strict sense. Their common feature is low solubility in low-boiling organic solvents and generation of liquid organic products on thermal decomposition.
The oldest and the most common extraction method involves pyrolysis (also known as "retorting" or destructive distillation). In this process, oil shale is heated in the absence of oxygen until its kerogen decomposes into condensable shale oil vapors and non-condensable combustible oil shale gas. Oil vapors and oil shale gas are then collected and cooled, causing the shale oil to condense. In addition, oil shale processing produces spent oil shale, which is a solid residue. Spent shale consists of inorganic compounds (minerals) and char—a carbonaceous residue formed from kerogen. Burning the char off the spent shale produces oil shale ash. Spent shale and shale ash can be used as ingredients in cement or brick manufacture. The composition of the oil shale may lend added value to the extraction process through the recovery of by-products, including ammonia, sulfur, aromatic compounds, pitch, asphalt, and waxes.
By early 1860, there were between 60 and 75 shale oil companies in the United States, producing from seven to nine million gallons annually of lamp and lubricating oil. Lamp oil from shale was reportedly much improved, and free from its early problems of smoke and odor. It was hailed as giving “more and cheaper light than any other substance,” and was driving the turpentine-based (camphene) lamp oils, as well as the much more expensive whale oil, from the market.
Scottish Oils Ltd, established by Anglo-Persian in 1919 by merging five Scottish oil shale companies (Young's Paraffin Light & Mineral Oil Company, Broxburn Oil Company, Pumpherston Shale Oil Company, Oakbank Oil Company and James Ross & Company Philpstoun Oil Works), was a producer of shale oil. Shale oil production in Scotland ceased in the early 1960s but there was an unsuccessful attempt to revive it in 1973. The company was wound up on 15 December 2010. The Scottish Oil Agency Ltd was a distributing and selling organisation of Scottish Oils Ltd. A Scottish Oil Agency rail tanker is preserved at the Museum of the Scottish Shale Oil Industry.