Abbreviation for exploration and production. ENHANCED OIL RECOVERY (EOR)
A process whereby oil is recovered other than by the natural pressure in a reservoir. EXPLORATION/EXPLORATION WELL
Exploration is the process of identifying a prospective hydrocarbon region and structure, mainly by reference to regional, and specific, geochemical, geological and geophysical (seismic) surveys. An Exploration Well is a well drilled to test a potential but unproven hydrocarbon trap or structure where good reservoir rock and a seal or closure combine with a potential source of hydrocarbons.
In geology, the composition and characteristics of a rock formation.FARM IN
When a company acquires an interest in a block by taking over all or part of the financial commitment for drilling an exploration well. FARMOUT
An arrangement under which a portion of an interest in petroleum and natural gas rights is assigned in consideration for the assignee agreeing to explore or drill (and perhaps equip) one well or several wells at his sole expense; subsequent development and equipment cost, if any, and income and operating expenses are shaped by participants on an agreed basis. FAULT/FAULT BLOCK
A discontinuity in a rock formation caused by fracturing of the earth's crust. In oilfield terms a Fault Block is a compartment of a rock formation surrounded or partly surrounded by faults, which may have sealed in hydrocarbons separately from the rest of the formation.FEED
Front end engineering design. Conceptual design prior to detailed design.FIELD
An area consisting of a single reservoir or multiple reservoirs all grouped on, or related to, the same individual geological structural feature or stratigraphic condition. The field name refers to the surface area, although it may refer to both the surface and the underground productive formations.FILTER CAKE/FILTRATE
Build up of mud solids or filtrate on the wall of a well. This helps seal and stabilize the rock face, but too much can cause sticking of the drill string. See also Differential Pressure.FISH/FISHING
Any unwanted object down a well, commonly the lower end of a drill string which has broken off. "Fishing" is trying to recover the Fish, using various attachments to the drill stem or wireline, known as fishing tools.FLOWING PRESSURE
Pressure registered at the wellhead of a flowing well. FLOWING BOTTOM HOLE PRESSURE
Bottom hole pressure measured at a given flow rate.FOOTAGE/FOOTAGE RATE
Penetration rate in drilling. Footage Rate may also be a form of remuneration under a drilling contract. Often referred to as ROP (Rate of Penetration).FORMATION
A rock deposit or structure of homogeneous origin and appearance.FORMATION DAMAGE
Damage to the reservoir rock around a well due to e.g. plugging with mud, or infiltration by water from the well.FRACTURING
The process of cracking open the rock formation around a well bore to increase productivity. This is normally done by applying hydraulic pressure down the well bore. FREEHOLD LEASE
An agreement with an individual which provides for the petroleum and natural gas rights underlying a given area. FREEHOLD ROYALTY
A royalty based on production paid to the owner (anyone other than the crown) of the producing lease.
Free gas, separate from, but overlying an oil zone that occurs within the same producing formation as oil. Since gas is lighter, it occupies the upper part of the reservoir. GAS KICK
Increase of down hole pressure above that exerted by the column of drilling fluid in a well, allowing gas to escape to the surface. If not controlled this could develop into a blowout.GAS/OIL RATIO (GOR)
The proportional amount of gas to oil liquid occurring in production from a reservoir, usually expressed as cubic feet per barrel.
Distinct layer or group of layers of rock. HYDROCARBONS
Organic chemical compounds of hydrogen and carbon whose densities, boiling points, and freezing points increase as their molecular weights increase. The molecular structure of the most common petroleum hydrocarbon compounds varies from the simplest - methane, a constituent of natural gas - to the very heavy and complex.
A rock with restricted or poorly-communicating pore spaces, such that hydrocarbons will not flow through it.INFILL DRILLING
Drilling of wells according to a planned pattern and spacing to achieve full production from a new field. IN PLACE
Description of the total hydrocarbon content of a reservoir, as distinct from 'Reserves' which can be 'recovered' or produced. Oil or gas in place (OIP, GIP) before the start of production is known as Oil or Gas Originally in Place or Initially in Place. (e.g. STOOIP = Stock Tank Oil Originally in Place; GIIP = Gas Initially in Place).
Down hole tools inserted in the drill-string when fishing to jerk or jar the fish free by repeated sudden blows. They may also be used while drilling to avoid the drill-string becoming stuck. JOINT
A single length of pipe. Coupled or welded to other lengths, joints become a string. The term joint may also refer to the couplings or joints themselves.JUNK
Any unwanted object 'lost' down a well.