Oil and Natural Gas Price Data - GASearch Energy Intelligence

C + F	Cost and Freight

Cabinda Crude Oil	Angola crude oil with gravity of * with a sulfur content of * %.

Cable Tool	One of two principal methods of drilling for gas and oil; the other is rotary. Cable tool, the older method, consists of raising and dropping a heavy drill bit, suspended from the end of a cable, so that it pounds and pulverizes its way through the subsurface structures. Water in the hole keeps the cuttings in suspension for removal at intervals by bailing.

Cable Tool Drill	Drilling that operates on a combination hammer suction principle.

Cakerawala Crude Oil	Crude oil from Malaysia with an API gravity of * and sulfur content of * %

Cal Canal Crude Oil	Crude oil from United States California with an API gravity of * and sulfur content of * %

Calibrate	To ascertain, usually by comparison with a standard, the locations at which scale or chart graduations should be placed to correspond to a series of values of the quantity which the instrument is to measure, receive or transmit. Also, to adjust the output of a device, to bring it to a desired value, within a specified tolerance for a particular value of the input. Also, to ascertain the error in the output of a device by checking it against a standard.

California Energy Natural Gas Hub	California natural gas hub - 5 pipeline interconnects

Calorimeter	An apparatus for measuring the amount of heat released by the combustion of a compound or mixture.

Camar Crude Oil	Crude oil from Indonesia with an API gravity of * and sulfur content of * %

Canadian Mixed Light Sour Crude Oil	Mixed light sour crude oil delivered at Edmonton, Alberta, Canada with an API gravity of * and * % sulfur content

Canadon Seco Crude Oil	Crude oil from Caleta Olivia, Argentina with API gravity of * and * % sulfur content

Cannel Coal	A compact, tough variety of coal, originating from organic spore residues, that is noncaking, contains a high percentage of volatile matter, ignites easily, and burns with a luminous smoky flame.

Cano Limon Crude Oil	Colombia crude oil from Covenas, Colombia with API gravity of * and * % sulfur content.

Capacity Assignment / Brokering	The sale or assignment of a specific right to firm transportation (or storage) on an interstate natural gas pipeline to another entity. In some instances, transportation capacity rights may be rebrokered. The FERC Commission's general policy is to require the initial assignor or broker to remain obligated to the pipeline for scheduling and payment of charges.

Capacity Peaking	The capability of facilities or equipment normally used to supply incremental natural gas under extreme demand conditions; generally available for a limited number of days at a maximum rate.

Capacity Release	A mechanism by which holders of firm interstate transportation capacity can relinquish their rights to utilize the firm capacity to other parties that are interested in obtaining the right to use that capacity for a specific price, for a given period of time and under a specifically identified set of conditions. The firm transportation rights may include transmission capacity and/or storage capacity.

Capacity Rights	Refers to the level of firm transportation service to which a customer has a contractual right.

Caprock	The impervious geological stratum that overlays the reservoir rock and retains gas or oil in a reservoir.

Caprock Crude Oil	Crude oil from United States Texas with an API gravity of * and sulfur content of * %

Captain Crude Oil	Crude oil from United Kingdom with an API gravity of * and sulfur content of * %

Captive Coal	Coal produced and consumed by the mine operator, a subsidiary, or parent company (for example, steel companies and electric utilities).

Caranda Crude Oil	Crude oil from Bolivia with an API gravity of * and sulfur content of * %

Carbon / Hydrogen Ratio	The ratio, either on a weight or on a molecular basis, of carbon-to-hydrogen in a hydrocarbon material. Materials with a high carbon/hydrogen ratio (e.g., coal) are solid. The ratio is useful as a preliminary indication of the hydrogen quantity needed to convert the hydrocarbon to a gas and/or liquid.

Carbon Black	Almost pure amorphous carbon consisting of extremely fine particles, usually produced from gaseous or liquid hydrocarbons by controlled combustion with a restricted air supply or by thermal decomposition.

Carbon Dioxide	A colorless, odorless, gaseous compound of carbon and oxygen (CO2) that is a product of incomplete combustion.

Carbon Monoxide (CO)	A poisonous, combustible gas formed by incomplete combustion of carbon, or reduction of carbon dioxide.

Caripito 17 Crude Oil	Crude oil from Venezuela with an API gravity of * and sulfur content of * %

Caripito 24 Crude Oil	Crude oil from Venezuela with an API gravity of * and sulfur content of * %

Carmopolis Crude Oil	Crude oil from Brazil with an API gravity of * and sulfur content of * %

Caroline Condensate Oil	Crude oil from Canada with an API gravity of * and sulfur content of * %

Carpenteria Crude Oil	Crude oil from United States California with an API gravity of * and sulfur content of * %

Carthage Natural Gas Hub	East Texas natural gas hub.

Carthage Natural Gas Hub	East Texas natural gas hub - 14 pipeline interconnects

Casablanca Crude Oil	Crude oil from Spain with an API gravity of * and sulfur content of * %

Cased	Descriptive of wellbore in which steel pipe, called casing, is run and cemented.

Cash Market	The physical market underlying a futures or options contract.

Cashout Provisions	To the extent a shipper violates balancing provisions, any difference between receipts and deliveries will be "cashed out", with the pipeline purchasing excess receipts at below-market prices and selling receipt shortages at above-market prices.

Casing	Metal pipe inserted into a wellbore and cemented in place to protect both subsurface formations (such as groundwater) and the wellbore. A surface casing is set first to protect groundwater. The production casing is the last one set. The production tubing (through which hydrocarbons flow to the surface) will be suspended inside the production casing.

Casing, Well	Steel pipe inserted (and sometimes cemented) into a gas or oil well, intermittently as the well is drilled, to line the well as is found necessary to eliminate ground caving and water infiltration, and to prevent gas and/ or oil from escaping or leaking from the native reservoir into other formations.

Casing-Tubing Annulus	Space between the surface casing and the production casing.

Casinghead Gas	Gas found naturally in oil and produced with the oil.

Casinghead Gas	Unprocessed natural gas containing natural gasoline and other liquid hydrocarbon vapors produced from an oil well. Frequently called WET GAS, ASSOCIATED GAS (but not all wet gas or associated gas is casinghead gas), and in the past, BRADENHEAD GAS. Technically, the term should apply only to gas produced from the casing of an oil well, and not from the tubing, but it is often applied to any gas produced in association with oil.

Castilla Crude Oil	Crude oil from Colombia with an API gravity of * and sulfur content of * %

Castilla Mix Crude Oil	Crude oil from Colombia with an API gravity of * and sulfur content of * %

Cat Gasoline	A gasoline blending component made in a cat cracker. (also Cat Naphtha)

Cat gasoline (cat naphtha)	A gasoline blending component made in a cat cracker.

Catalytic Cracking	The decomposition or breaking down of oil or hydrocarbons through the action of a catalyst and heat.

Catfeed	Feedstock to a catalytic cracker, usually vacuum gasoil.

Cathodic Protection	A technique to prevent the corrosion of a metal surface by making that surface the cathode of an electrochemical cell.

Cecil Lake Crude Oil	Crude oil from Canada with an API gravity of * and sulfur content of * %

Ceiba Crude Oil	Crude oil from Equatorial Guinea with an API gravity of and sulfur content of * %

Ceiling Price	The maximum lawful price which may be charged for regulated gas.

Celsius Scale	Favored name for centigrade scale, with freezing points and boiling points of water at 0 degrees and 100 degrees, respectively.

CenterPoint Natural Gas Hub	Arkansas - Louisiana - East Texas natural gas hub

Cerro Negro Crude Oil	Crude oil from Venezuela with an API gravity of * and sulfur content of * %

Certificate	when used with respect to the Natural Gas Act [15 U.S.C. 717 et seq.], means a certificate of public convenience and necessity issued under such Act.

Certificate of Necessity (for Amortization)	A certificate issued by a Federal authority certifying that certain facilities are necessary in the interest of national defense, which permits accelerated amortization of the cost of the facilities or a certain specified percentage thereof, for income tax purposes, over a 60-month period.

Certificate of Public Convenience and Necessity	A special permit (which supplements the franchise), commonly issued by a state commission, which authorizes a utility to engage in business, construct facilities, or perform some other service. Also, a permit issued by the Federal Energy Regulatory Commission to engage in the transportation or sale for resale of natural gas in interstate commerce or to construct or acquire and operate any facilities necessary therefore, to which certificate the Commission may attach such reasonable terms and conditions as the public convenience and necessity may require.

Certificated natural gas	means natural gas transported by any interstate pipeline in a facility for which there is in effect a certificate issued under section 7(c) of the Natural Gas Act [15 U.S.C. 717f (c)]. Such term does not include natural gas sold to the user by the producer and transported pursuant to a certificate which is specifically issued under section 7(c) of the Natural Gas Act for the transportation of that natural gas, for such user unless such natural gas is used for the generation of electricity.

Certified Capacity	The total certified capacity of a pipeline is the sum of the increments authorized in various certificates by the FERC. If a particular construction program will change the transmission or storage capacity of the pipeline, the certificate filing must explain the change.

Cetane	A paraffinic hydrocarbon used hydrocarbon used as an additive in diesel fuel.

Cetane	A paraffinic hydrocarbon used as an additive in diesel fuel.

Cetane Number	Number equal to the percentage by volume of cetane added to basic diesel fuel to achieve specific ignition performance characteristics.

Cetane Number	Number equal to the percentage, by volume, of cetane added to basic diesel fuel to achieve specific ignition performance characteristics.

Ceuta Crude Oil	Crude oil from Venezuela with an API gravity of * and sulfur content of * %

CFD	Contract For Differences. A type of crude oil swap.

Chad Blend Crude Oil	Crude oil from Chad with an API gravity of * and sulfur content of * %

Challis Blend Crude Oil	Crude oil from Australia with an API gravity of * and sulfur content of * %

Champion Crude Oil	Crude oil from Brunei with an API gravity of * and sulfur content of * %

Check Meter	A device for measuring utility service consumption within individual dwelling units where the utility service is supplied through a master meter.

Cheleken Crude Oil	Crude oil from Turkmenistan with an API gravity of * and sulfur content of * %

Cheyenne Natural Gas Hub	Northeast Colorado natural gas hub.

Cheyenne Natural Gas Hub	Colorado natural gas hub - 5 pipeline interconnects

Chicago Natural Gas Hub	Midwest natural gas hub - 10 pipeline interconnects

Chichimene Crude Oil	Crude oil from Colombia with an API gravity of * and sulfur content of * %

China Walls	An expression that refers to the complete separation of operations for affiliated companies within a corporation to prevent undue business advantages. Pipeline companies, for example, are expected to have "china walls" separating their transportation departments from marketing affiliates to ensure that all customers moving gas on the pipeline get equal treatment.

Chiraq Blend Crude Oil	Crude oil from Azerbaijan with an API gravity of * and sulfur content of * %

Christmas Tree	The system of pipes, valves, gauges and related equipment that is located on the well at ground level and that controls the flow of gas and other petroleum products produced from the well.

Chromatograph	An instrument used to analyze the make-up of various substances, and often used to determine the Btu content of natural gas.

Chuncula Crude Oil	Crude oil from United States Alabama with an API gravity of * and sulfur content of * %

CIF	Cost, insurance and freight charges for shipping products. CIF prices include these charges.

CIG (Colorado Interstate Gas�) Natural Gas Hub - Rocky Mountains	Colorado - Utah - Wyoming natural gas hub

Cinta Crude Oil	Crude oil from Cinta, Indonesia with API gravity of * and sulfur content of * %

City Gate Rate	The rate charged a distribution company by its supplier(s). It refers to the cost of the gas at the point at which the distribution utility takes title to the gas.

Citygate	Location point, indicating where the natural gas transmission lines end and the local natural gas mains begin.

Clair Crude Oil	Crude oil from United Kingdom with an API gravity of * and sulfur content of * %

Class of Service	Defines the type of customer. The common classes of service applied to ultimate consumers, and considerably more completely described in the A.G.A. publication "Definitions of a Gas Customer and Classes of Service for Industry Reporting Purposes", are: 1.Residential Service: Covers service to customers for domestic purposes (single, multifamily, or mobile homes, etc.). In residential service, the number of housing units within a structure determines the customer classification. 2.Commercial Service: Covers service to customers engaged in wholesale or retail trade, agriculture, communications, finance, fisheries, forestry, government, insurance, real estate, transportation, etc., and to customers not directly involved in other classes of service. 3.Industrial Service: Covers service to customers engaged primarily in a process which either involves the extraction of raw materials from the earth or a change of raw unfinished materials into another form or product.

Clause, Adjustment	A provision in a utility tariff which provides for periodic changes in charges or credits to a customer due to increases or decreases in certain costs over or under those included in base rates and incurred by the seller such as purchased gas cost, transportation costs, or advance payments made for gas.

Claymore Crude Oil	Crude oil from North Sea with an API gravity of * and sulfur content of * %

Clear Gas	Tar free gas occurring between the carbonization and gasification zones in a coal gasification plant.

Cloud Point	The temperature at which a fuel, when cooled, begins to congeal and take on a cloudy appearance due to bonding of paraffins.

CME	Chicago Mercantile Exchange. Also known in the energy industry as "the Merc".

CNG	Compressed natural gas.

Coal	A readily combustible black or brownish-black rock whose composition, including inherent moisture, consists of more than 50 percent by weight and more than 70 percent by volume of carbonaceous material. It is formed from plant remains that have been compacted, hardened, chemically altered, and metamorphosed by heat and pressure over geologic time.

Coal Carbonized	The amount of coal decomposed into solid coke and gaseous products by heating in a coke oven in a limited air supply or in the absence of air.

Coal Equivalent of Fuels Burned	The quantity of coal (tons) of a stated kind and heat value which would be required to supply the Btu equivalent of all fuels burned. In determining this coal equivalent, the Btu content of other fuels is generally divided by the representative heat value per ton of coal burned.

Coal Gas	Manufactured gas made by distillation or carbonization of coal in a closed coal gas retort, coke oven, or other vessel.

Coal Gasification	A controlled process of reacting coal, steam, and oxygen under pressure and elevated temperature. The crude gas is purified and has a low heating value. Subsequent catalytic upgrading can be employed to produce high-Btu pipeline grade gas.

Coal Liquefication (Coal Hydrogenation)	The conversion of coal into liquid hydrocarbons and related compounds by hydrogenation.

Coal Oil Pt Crude Oil	Crude oil from United States California with an API gravity of * and sulfur content of * %

Coal Rank	Classification of coal based on carbon content and fuel value.

Coal Seam Gas	See COALBED METHANE.

Coalbed Methane	Methane derived from a coal seam.

Coalinga East Crude Oil	Crude oil from United States California with an API gravity of * and sulfur content of * %

Coastal B-1 Crude Oil	Crude oil from United States Texas with an API gravity of * and sulfur content of * %

Coastal B-2 Crude Oil	Crude oil from United States Texas with an API gravity of * and sulfur content of * %

Coastal Crude Oil	Crude oil from United States Texas with an API gravity of * and sulfur content of * %

Coban Blend Crude Oil	Crude oil from Guatemala with an API gravity of * and sulfur content of * %

Cobia Crude Oil	Crude oil from Australia with an API gravity of ***

Coco Crude Oil	Crude oil from Congo (Kinshasa) with an API gravity of * and sulfur content of * %

Cogeneration	The use of a single prime fuel source in a reciprocating engine or gas turbine to generate electrical and thermal energy in order to optimize the efficiency of the fuel used. The dominant demand for energy can be either electrical or thermal. Usually it is the latter with excess electrical energy, if any, being transmitted into the local power supply company's lines (with a reciprocal situation existing when electrical demands exceed the cogeneration plant's output). A parallel exists with total energy plants, which are typically designed for the electrical demands rather than thermal. Under the 1978 Public Utility Regulatory Policies Act (PURPA), regulated utilities are required to purchase electricity furnished by cogenerators and small power producers at rates set by regulatory bodies having jurisdiction over the utility receiving the electricity based on "full avoided cost."

Cohasset Condensate Oil	Crude oil from Canada with an API gravity of * and sulfur content of * %

Coke	A solid material similar to coal that can be produced from processing of heavy oil.

Coke (coal)	A solid carbonaceous residue derived from low-ash, low-sulfur bituminous coal from which the volatile constituents are driven off by baking in an oven at temperatures as high as 2,000 degrees Fahrenheit so that the fixed carbon and residual ash are fused together. Coke is used as a fuel and as a reducing agent in smelting iron ore in a blast furnace. Coke from coal is gray, hard, and porous and has a heating value of 24.8 million Btu per short ton.

Coke (petroleum)	A residue high in carbon content and low in hydrogen that is the final product of thermal decomposition in the condensation process in cracking. This product is reported as marketable coke or catalyst coke. The conversion is 5 barrels (of 42 U.S. gallons each) per short ton. Coke from petroleum has a heating value of 6.024 million Btu per barrel.

Coking	A refining process by which the denser, heavier products of the distillation process (residuals) are converted to lighter products such as cat feed and naphtha, and petroleum coke, a solid, coal-like fuel. The coking unit, or coker, heats hydrocarbons to near 800 degrees Fahrenheit, at which temperature all the lighter products vaporize and the coke solidifies in a large drum called a coke drum from which it is removed by means of high-pressure jets of water.

Cold Lake Crude Oil	Crude oil from Canada with an API gravity of * and sulfur content of * %

Columbia Gas Natural Gas Hub - Appalachian	Appalachian natural gas hub

Columbia Gas Natural Gas Hub - Mid-Atlantic	Mid-Atlantic natural gas hub

Columbia Gulf Natural Gas Hub - Louisiana	Louisiana natural gas hub

Combustion	Rapid chemical reaction of oxygen with fuel accompanied by the production of heat, or heat and light.

Commingled Gas	A homogeneous mix of gas obtained from various physical and contractual supply sources.

Commission	Federal Energy Regulatory Commission (FERC), or local public utility regulatory commission (PUC).

Commodity Charge	A charge per unit volume or heat content (i.e., therm) of gas delivered to the buyer.

Commodity Costs (Rate)	That part of the total cost of service which must be recovered through use of a commodity rate; i.e., a rate for each Mcf of gas sold. Revenue from a commodity rate varies with throughput.

Common Carriage	The obligation to carry, for a fee, gas that belongs to another party.

Completion	A general term referring to all activities necessary to put a well on production after it has been drilled to casing point, including the installation of permanent equipment for the production of oil or gas.

Compressed Natural Gas ("CNG")	The compression of natural gas in storage vessels to pressures of 2,400 to 3,600 pounds per square inch, generally for use as a vehicle fuel.

Compressed Natural Gas (CNG)	Natural gas in high-pressure surface containers that is highly compressed (though not to the point of liquefaction). CNG is used extensively as a trans-portation fuel for automobiles, trucks and buses in some parts of Italy, New Zealand, and in Western Canada, and has recently begun to penetrate some regions of the United States. Small amounts of natural gas are also transported overland in high-pressure containers.

Compression	Natural gas is compressed during transportation and storage. During transportation and storage, gas is compressed to save space. Pipelines have compressing stations installed along the line (one about every 100 miles) to ensure that the gas pressure is held high while the gas is being transported. Pressure in pipelines serving residential neighborhoods is generally much lower than the pressure on interstate pipelines.

Compressor	A mechanical device for increasing the pressure of a gas.

Compressor Fuel	Natural gas consumed by the engines in a compressor station, reported as a percentage of the gas transported through the station. Thus, a transporter whose gas passes through one or more compressor stations will be entitled to take delivery of less than 100 percent of the gas introduced into the pipeline network.

Compressor Station	Any permanent combination of facilities which supplies the energy to move gas at increased pressure from fields, in transmission lines, or into storage.

Condensate (also called Lease Condensate)	Liquid hydrocarbons separated from gas production. Very high API crude "oil", which in its natural state is in gaseous form but which condenses to liquid upon production.

Confirmed Nomination	An agreement by a seller to deliver/cause delivery or a transporter to receive and deliver a specific quantity of gas for a specified period at various points under a Sales or Transportation Agreement or for all contracts at one specific point. The confirmed nomination is in response to a purchaser's or shipper's nomination.

Consumers Energy Natural Gas Hub - City Gate	Central Michigan natural gas hub

Contango	Market situation where prices are progressively higher for forward delivery dates than for nearer delivery dates.

Content of Fuel	The heat value per unit of fuel expressed in Btu as determined from tests of fuel samples. Examples: Btu per pound of coal, per gallon of oil, per cubic foot of gas.

Contract Balancing	A process of managing the difference between the quantities received and delivered at various points under a contract during a defined period of time (i.e., hourly, daily, monthly, etc.).

Contract Demand	The maximum daily, monthly, seasonal or annual quantities which the supplier agrees to furnish, or the pipeline agrees to transport and for which the buyer or shipper agrees to pay a demand charge.

Contract Imbalance Quantity	The cumulative difference between all quantities of gas received and quantities of gas delivered for a contract from inception through the most current billing period.

Contract Storage	Storage facilities, or a portion of storage facilities, which are leased to others for the purposes of storing gas. The portion of storage facilities which has been made available to others may not be used by the pipeline for system supply.

Conversion	The stage in the refining process consists of breaking up the large molecules into smaller ones in order to produce lighter compounds. Processes involved include catalytic cracking and viscosity reduction (visbreaking).

Conversion Factors	1 Barrel (42 gallons) of Crude Oil = 5,800,000 BTU 1 Gallon of Gasoline = 124,000 BTU 1 Gallon of Heating Oil or Diesel Fuel = 139,000 BTU 1 Gallon CNG = 88,000 Btu 1 Gallon # 2 Oil = 135,000 BTU 1 Gallon # 6 Oil = 144,000 BTU 1 Gallon Propane = 91,600 BTUs on average 1 Pound Propane = 21,500 BTU 1 Ton Coal (Anth) = 27,000,000 BTU 1 Ton Coal (Bit) = 26,000,000 BTU 1 Short Ton = 0.907 ton = 2,0000 pounds 1 Long Ton = 1.016 ton = 2,240 pounds 1 Ton = 1 Metric Ton = 1,000 kilorgram = 2,205 pounds 1 Cubic Foot of Natural Gas = 1,026 BTU 1 KiloWattHour of Electricity = 3,412 BTU 1 Acre = 0.405 Hectare 1 Ton of LNG = appx 48,000 CF natural gas 1 Cubic Meter = 35.315 Cubic Feet 1 Kilometer = 0.62 mile

Conversion to Natural Gas	Changing the gas service to ultimate customers from a fuel other than natural gas to natural gas, including adjustment of consumers' appliances to perform satisfactorily with natural gas. Natural gas does not necessarily mean straight natural gas; stabilizing the heat content of the sendout gas by diluent gases or enriching gases is not considered to change the basic character of natural gas. For the purpose of uniform reporting, a company should be considered a natural gas company when 95 percent of the system has been converted.

Cook Inlet Crude Oil	Crude oil from United States Alaska with an API gravity of * and sulfur content of * %

Cooling Tower	A structure which cools heated refining process water by circulating the water through a series of louvers and baffles through which cool air is forced by large fans.

Cooper Basin Crude Oil	Crude oil from Australia with an API gravity of * and sulfur content of * %

Core-Sampling (or Coring)	During drilling, cylindrical samples of rock known as "core samples" are removed in order to study the characteristics of the terrain.

Cossack Crude Oil	Crude oil from North West Australia. API gravity of * with sulfur content of * %

Council of Petroleum Accountants Societies (COPAS)	An organization that publishes industry guidelines for oil and gas accounting and shipping.

CPC Blend (CIF Augusta)	This daily spot assessment takes into account cargoes loading from Black Sea port CPC Terminal for delivery into the Mediterranean. The assessments are based on CIF Augusta, Sicily/Italy. The API gravity for CPC Blend is * degrees and the sulfur content is * %.

CPC Blend Crude Oil	Crude oil from Kazakhstan with an API gravity of * and sulfur content of * %

CPC Blend Crude Oil	CPC Blend is a light crude oil which was first introduced to the market at the end of 2001 with the commissioning of a 1,580km pipeline by the Caspian Pipeline Consortium (CPC). The CPC pipeline links major oil fields in Western Kazakhstan to a Black Sea export terminal opened in 2001 at Yuzhnaya Ozereevka, located 40km North-West of Novorossiysk (Russia). At the end of 2004, CPC Blend consisted of seven crude oil streams: Tengiz, Aktobe, Kumkol, Martyshi, Arman, Karachaganak and Siberian Light. The most significant developments in 2004 were the introduction of Karachaganak in June, and the beginning of Russian crude injection, principally Siberian Light, in November. Despite new streams being injected to the pipeline, Tengiz remains the single largest component of CPC Blend.

CPI	Consumer Price Index

Crack	To get the most use of crude oil, American Refineries separate or "crack" the crude into more practical fuels such as ethane, methane, propane, gasoline, kerosene, diesel (#2 oil), #4 oil, #6 oil, and byproducts.

Crack Spread	The simultaneous purchase or sale of crude against the sale or purchase of refined petroleum products. These spread differentials which represent refining margins are normally quoted in dollars per barrel by converting the product prices into dollars per barrel and subtracting the crude price.

Cracked	Molecules broken by certain refining processes...the opposite of straight-run.

Cracked fuel	Residue remaining after a straight run fuel has been processed by enhanced refining methods such as catalytic cracking.

Cracking	Refining process to break large molecules into smaller ones. Principal cracking techniques are: (1) Thermal cracking, (2) Visbreaking, (3) Delayed Coking, (4) Catalytic cracking, (5) Hydrocracking, (6) Steam cracking, (7) Co-Cracking

Cracking	Processing that breaks down and rearranges the molecular structure of hydrocarbon chains. In thermal cracking, high temperature and high pressures are applied; in catalytic cracking, temperature and pressure are applied in the presence of a catalyst.

Crawford Crude Oil	Crude oil from North Sea with an API gravity of * and sulfur content of * %

Cromer Light Sour Blend Crude Oil	Light sour blend crude oil injection at Cromer, Canada with an API gravity of * and sulfur content of * %

Cromer Light Sour Crude Oil	Light sour crude oil delivered at Cromer, Canada API gravity of * and a sulfur content of * %

Cromer Midale Crude Oil	Medium, sour crude oil delivered at Cromer, Canada with API gravity of * and sulfur content of * %

Crossfield Natural Gas Hub	Alberta, Canada natural gas hub

Crude Oil	Liquid petroleum as it comes out of the ground as distinguished from refined oils manufactured out of it.

Crude Oil	A geological liquid consisting of hydrocarbons and relatively small amounts of sulfur, nitrogen, and oxygen in the form of derivatives of hydrocarbons. Crude is formed under pressure from residual plant matter accumulated in a swamp over a period of time. It may come from the earth with varying quantities of water, gas, and other organic matter. Some crudes are very volatile and others are very viscous liquids. Crude oil may contain such impurities as sulfur and hydrocarbons. These are compounds containing a variety of combinations of carbon with hydrogen. There are a very large number of these compounds and they form the basis of a number of petroleum products. These compounds may exist as gases or liquids or solids. A number of hydrocarbons are also contained in bituminous coal, oil shale and tar sands. Crude is generally classified into three basic types: paraffin base crude oils contain a high degree of paraffin wax and little or no asphalt. Besides wax, they also yield large amounts of high-grade lubricating oil. Asphalt base crudes contain large proportions of asphaltic matter, and mixed base crudes contain quantities of both paraffin wax and asphalt. This is why crude oils do not always look alike. Some are almost colorless or pitch black. Others can be amber, brown or green. They may flow like water or creep like molasses. Some crudes, containing relatively large amounts of sulfur and other mineral impurities, are called "sour" crudes. Others, having a fairly low sulfur content, are called "sweet" crudes.

Crude Oil Types	Paraffin-Base Crude Oils : These contain higher molecular weight paraffins which are solid at room temperature, but little or no asphaltic (bituminous) matter. They can produce high-grade lubricating oils. Asphaltic-Base Crude Oils : Contain large proportions of asphaltic matter, and little or no paraffin. Some are predominantly naphthenes so yield a lubricating oil that is more sensitive to temperature changes than the paraffin-base crudes. Mixed-Base Crude Oils : The "gray area" between the two types above. Both paraffins and naphthenes are present, as well as aromatic hydrocarbons. Most crudes fit this category.

Crude Types	Crude oil quality is defined by its density and sulfur content. Density is given in degrees API (American Petroleum Institute) The higher numbers represent lighter oils and are called light crudes. For example, heavy crude is usually less than API 20 degrees and is very thick and viscous (think about the heaviest molasses you ever saw). Sweet crude oil has sulfur content less than 0.5%. Sour crude has a maximum sulfur content of 1.99%. Sweet crudes are preferred because they produce high yields of high value products like gasoline, diesel, heating oil and jet fuel. Generally, specific crude oils are given names, which imply both location and certain characteristics. For example, Brent crude, which is one of the standards on the commodities market, is API 36 degrees with low sulfur content. It would be called “Light Sweet Crude.”

CST	Centistokes - A way of measuring viscosity similar to seconds.

Cubic Foot of Gas or Standard Cubic Foot of Gas	As a unit of volume, 1,728 cubic inches. As applied to water, 7.48 gallons. As applied to natural gas, the volume of gas which, when saturated with water vapor at 60ºF and at a pressure of 30 inches of mercury occupies one cubic foot of volume.

Culm	Waste from Pennsylvania anthracite preparation plants, consisting of coarse rock fragments containing as much as 30 percent small-sized coal; sometimes defined as including very fine coal particles called silt. Its heat value ranges from 8 to 17 million Btu per short ton.

Cupiagua Blend Crude Oil	Crude oil from Colombia with an API gravity of * and sulfur content of * %

Curlew Crude Oil	Crude oil from North Sea with an API gravity of * and sulfur content of * %

Curtailment	A restriction or interruuption of natural gas supplies or deliveries. May be caused by production shortages, pipeline capacity, or operational constraints, or a combination of operational factors.

Cushing Crude Oil	Crude oil from United States Oklahoma with an API gravity of * and a sulfur content of * %.

Cushion Gas	The gas required in a reservoir used for storage of natural gas so that the reservoir pressure is such that the storage gas may be recovered.

Cusiana Blend Crude Oil	Crude oil from Colombia with an API gravity of * and sulfur content of * %

Cusiana Crude Oil	Crude oil from Colombia with API gravity of * and * % sulfur content.

Cymric Crude Oil	Crude oil from United States California with an API gravity of * and sulfur content of * %

Cyrus Crude Oil	Crude oil from United Kingdom with an API gravity of * and sulfur content of * %