SpeakingOilGas

Seismic Surveyor – uses conventional optical or global positioning system technology to place the seismic line in the correct position and decides where to deflect lines to avoid major obstacles.

Survey Coordinator – the oil company representative responsible for the safe operation, conduct and productivity of all survey crews on the job.

Toolpusher – an experienced drilling engineer with direct responsibility for the work done by the drill crew on a rig.

Vibe Operator – a member of the seismic crew who drives the vibroseis trucks and operates the vibrators at specified points along the survey line.

Other Roles

In addition to the above, there are a number of positions in the petroleum industry that call for specialisation within broader professions. Examples include lawyers who specialise in areas like joint venture contracts, lease agreements and production sharing contracts. There are finance people liaising with banks and lending institutions and looking after project finance negotiations, and economists who become involved in corporate strategy. There are safety specialists and industrial relations people as well as those skilled in personnel and recruitment for the specialised jobs in the petroleum industry. And there are those involved in the medical side and community liaison. The petroleum industry, more than most, is made up of a vast range of skills and job descriptions.

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Appendix 2.

CONVERSION FACTORS

Product figures shown are typical. However the actual value for any particular sample of a product can differ to some extent from the typical figure, depending on crude oil source, method of refining or blending etc.

Abbreviations

Some common abbreviations and their metric equivalents used in the petroleum industry are:

M	= thousand	=	103	= k (kilo)
MM	= million	= 106		= M (mega)
B	= billion	=	109	= G (giga)
T	= trillion	=	1012	= T (tera)
–			1015	= P (peta)
–			1018	= E (exa)

APPENDIX 2. CONVERSION FACTORS

167

Equivalents

1 barrel	= 158.987 litres (L)
	= 34.9726 Imperial gallons
	= 42.000 USA gallons
1 kilolitre	= 6.2898 barrels (bbl)
	= 219.969 Imperial gallons
	= 264.172 USA gallons
1 Imperial gallon	= 0.02859 barrels
	= 4.546 litres
	= 1.2009 USA gallons
1 USA gallon	= 0.02381 barrels
	= 3.785 litres
	= 0.8327 Imperial gallons
1 cubic metre	= 1000 litres
	= 35.315 cubic feet
1 cubic foot	= 0.02832 cubic metres
1 megajoule	= 947.8 British thermal units (BTU)
	= 0.2778 kilowatt hours (kWh)
	= 0.009478 therm
1 therm	= 100,000 BTU
	= 29.31 kWh
	= 105.5 megajoules (MJ)

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To convert Volume	Multiply by
Litres to Imperial gallons	0.21997
Imperial gallons to litres	4.54609
USA gallons to kilolitres	0.0038
USA gallons to barrels	0.023
USA gallons to metric tonnes	0.00325
Barrels to metric tonnes	0.1364
Barrels to kilolitres	0.159
Barrels to USA gallons	42.00
Barrels per day to Imperial gallons per year	12765.0
Kilolitres per year to barrels per day	0.017232
Million tonnes LNG to billion cubic metres natural gas	1.38
Million tonnes of LNG to million barrels oil equivalent	8.68
Billion cubic metres natural gas to million tonnes LNG	0.7
Billion cubic feet natural gas to billion cubic metres	0.028
Billion cubic feet natural gas to million tonnes LNG	0.02
Billion cubic feet natural gas to million barrels oil equivalent	0.18
Billion cubic metres natural gas to millions barrels oil equivalent	6.29
To convert Mass	Multiply by
Tonnes to long tons	0.98421
Long tons to tonnes	1.01605
Kilograms to pounds	2.20462
Pounds to kilograms	0.45359

Courtesy Australian Institute of Petroleum

APPENDIX 2. CONVERSION FACTORS

169

Glossary

acidise – injecting acid solution down a well to dissolve carbonate rocks in a reservoir, or improve the flow of hydrocarbons to the well.

acoustic log – a measurement of the velocities of sound waves imparted to a formation in a well and used mainly for determination of rock porosity.

anomaly – a divergence from the background levels of physical or chemical properties of an area under survey.

anticline – an upfold in rock strata producing an arch or dome structure. One of the most common hydrocarbon traps.

API – American Petroleum Institute. API gravity is a standard method of measuring density of crude oils and is expressed in degrees.

appraisal well – a well or wells drilled to follow up a discovery and evaluate its commercial potential.

assay – a mini distillation process carried out in a laboratory to determine the exact composition and the physical properties of crude oil.

associated gas – natural gas found as part of or in conjunction with other constituents of crude oil, as opposed to gas found on its own.

AVO – amplitude variation with offset. This is a variation in seismic reflection amplitude with a change in the distance between the energy source and the geophone/hydrophone. It indicates differences in lithology and fluid content in rocks above and below the reflecting layer.

ballast – extra weight taken on to increase a ship’s stability to prevent rolling and pitching. Most ships use seawater as ballast. Empty tank space is filled with inert (non-combustible) gas to prevent the possibility of fire or explosion.

barite – a sulphate of barium used to add weight to drilling fluids.

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barrel (bbl) – measure of crude oil equal to 42 USA gallons, 35 Imperial gallons or 159 litres. Takes its name because the first oil produced in the USA was stored and transported in wooden barrels.

basin – a dip in the earth’s crust usually filled or being filled with sediment. It is a basic concept in petroleum geology.

bathymetry – relates to the measurement of water depths, usually referring to the ocean.

bentonite – a type of clay often added to drilling fluid because of its swelling properties when added to water.

bit – the cutting part of the drilling equipment.

blowout – when downhole pressure overcomes the weight of drilling fluid and rises in a well to the surface out of control. An underground blowout is where the overpressuring enters another formation higher in the well, but before it reaches the surface.

blowout preventer – a system of valves and rams set in a well which can be closed successively to counteract the uncontrolled rise of oil or gas from a reservoir below.

boe – barrels of oil equivalent. Afigure used when expressing the combined volume of oil and gas reserves.

bright spot – a point on a seismic profile which shows up brighter than surrounding traces because of an increase in amplitude of seismic waves passing from hydrocarbons to water within the pores of a rock.

calliper log – a measurement of the diameter of a well.

cap rock – an impermeable layer of rock that traps or halts the upward movement of oil and gas, forming the top or cap of a reservoir.

casing – steel pipe screwed together to line the inside of a well bore and cemented into place.

casing shoe – a heavy section steel tube fitted to the lower end of a casing string to protect the end of the string from damage when running into a well.

GLOSSARY

171

cat cracking – a secondary refining process which uses heat and the presence of a catalyst to ‘crack’ apart the molecules of the various components of crude oil obtained from the primary distillation process to form refined petroleum products.

cement bond log – a measurement of the strength and bonding of cement to the casing in a well.

choke – a valve or valves used to control the flow of hydrocarbons from a well by changing the diameter of the orifice.

Christmas tree – the system of valves and controls placed at the wellhead.

CIF – cost including freight, where the seller of a cargo of petroleum or petroleum product provides the transport to its destination.

city gate – the point at which high pressure pipelines deliver natural gas to low pressure pipelines for distribution to individual users.

closure – a term used to indicate that a trap exists in the subsurface and there are no avenues for hydrocarbons (if present) to escape.

completion – the final preparations to ready a well for production.

concession – an arrangement whereby an oil company is given exclusive permission by a government to explore a large portion of a country over a long period of time in return for an agreed percentage of any oil or gas production that results.

condensate – hydrocarbons which are gaseous in a reservoir, but which condense to form a liquid as they rise to the surface where the pressure is much less.

conductor – the first casing string in a well.

coning – this occurs when an oil well is produced at excessive rates. The reduction in reservoir pressure may draw up water underlying the oil and gas can be drawn down from an overlying gas cap.

coring – an operation whereby a sample of rock being drilled is allowed to pass through the centre of a special bit and be collected in a core barrel mounted directly behind it.

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crown block – an assembly of sheaves at the top of the drilling derrick of a rig over which the hoist lines are passed.

cuttings – the broken pieces of rock formed by the bit during drilling. These are flushed up the well and examined by the well site geologist to determine the type of formations being drilled.

darcy – the unit of measurement of permeability of rock.

delineation well – see appraisal well.

development well – a well drilled specifically into a previously discovered field for the purpose of producing oil or gas.

deviated well – a well whose path has been deliberately diverted from the vertical.

diamond bit – a drill bit with impregnated diamonds as the cutting edge.

dipmeter – an instrument lowered down the well to measure the dip of the drilled formations relative to the well.

directional well – see deviated well.

distillation – the refining process of separating crude oil components by heating and subsequently condensing of the fractions by cooling. The basic principle in refining is that of heating crude oil until various vapours or gases ‘boil off’, and then condensing them to form a condensate or distillate. The first to boil are the very light, dry gases; then highly volatile natural gasoline, kerosene, gas oil, light lube oil stock, and so on until heavy resin is left. This resin is broken up by other, more sophisticated processing.

distribution cost – usually refers to the cost of transporting gas to the consumer through low pressure pipelines and includes a fee for the pipeline owner.

distribution system – usually refers to the network of low pressure gas pipelines delivering gas to individual consumers.

downstream – refers to all petroleum operations occurring after delivery of crude oil or gas to refinery or fractionation plant.

GLOSSARY

173

downtime – the time an operation is postponed, usually due to bad weather or mechanical failure.

draw-works – the hoisting winch for handling drill pipe and casing on a rig.

drill collar – the top of a well, usually a cemented section from which the conductor pipe is hung.

drill pipe – steel pipe screwed together and used to carry and rotate the drilling tools in a well and to permit the circulation of drilling fluid.

drill stem test – a valved test tool is lowered down a well on the end of the drill string to a specific reservoir formation and the valve opened to admit formation fluids.

drill string – the column of drill pipe lengths screwed together.

drilling fluid – see drilling mud.

drilling line – the wire cable on a rotary rig, one end of which is wound around the drum of the draw-works and the other passes through the crown and travelling block sheaves to a fixed point on the derrick frame. As the wire round the drum is wound in or paid out, it is the means of raising and lowering the travelling block.

drilling mud (drilling fluid) – is the suspension of minerals and chemicals in oil or water which forms the well circulatory system.

drillship – a ship-shaped marine exploration drilling vessel usually with its own means of locomotion.

dry gas – natural gas (methane and ethane) with no significant content of heavier hydrocarbons.

dry tree – a subsea wellhead where the equipment is enclosed in a watertight chamber.

dynamic positioning – a method of keeping an offshore drilling rig on location without anchors using computer-controlled propellers around the vessel’s hull.

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electric logs – measurement of rock properties (e.g. resistivity, radioactivity) down a well which leads to determination of the rock types.

ethane – a component of natural gas and the basic feedstock for petrochemical industries.

extended reach well – a well in which the horizontal distance from the wellhead to the target location is much greater than the vertical depth to the reservoir horizon.

farminee – a company which earns an interest in an oil and gas permit from the company holding the lease. This may be done through a direct cash payment, a share trade or, more usually, by agreeing to pay all or some of the costs of a seismic survey, a drilling program or a development project on that permit.

farminor – a company holding the exploration or production rights in a permit which agrees to bring in another company to help defray the costs of its work program in return for allowing the newcomer to take a percentage interest in the permit.

farm-in/out – an arrangement between one or more parties and the company or group holding a lease title to an exploration or production area whereby the former pays to earn an interest in the permit. Payment may be in cash or in the form of a work program.

fault – a break or fracture in the earth’s sub-strata where one side of the break moves relative to the other.

FEED – front end engineering and design. This process provides definitive costs and technical data on a proposed project to enable a decision on final commitment to construction.

fishing – to retrieve equipment which has fallen into or is caught in the well.

flaring – the practice of burning off waste gas or oil as a safety measure in a refinery or during a test of an exploration well. It is rarely done during production as associated gas is used or returned to the reservoir.

flat spot – a flat trace on the seismic profile indicative of a fluid interface in the subsurface.

GLOSSARY

175