| Aptian | A geologic period, a sub-division of the early or lower Cretaceous period, that extends from about c.125 Mya (million years ago) to 112 Mya |
| Appraisal well | An appraisal well is drilled to assess the characteristics (e.g. flow rate, areal extent) of a discovered oil or gas accumulation |
| bbl | Barrel of oil; equivalent to 42 US gallons |
| bcf | Billion cubic feet of gas |
| boe | Barrels of oil equivalent where the gas component is converted into an equivalent amount of oil using a conversion rate of approximately 6mcf to one barrel of oil |
| boepd | Barrels of oil equivalent per day |
| bopd | Barrels of oil per day |
| Carbonate Rocks | Rocks made of particles (composed >50% carbonate minerals - limestones (CaCO3) and dolomites (CaMg(CO3)2)) embedded in a cement. They make up 10 - 15% of sedimentary rocks and dissolve in dilute acidic groundwater. Most carbonate rocks result from the accumulation of bioclasts created by calcareous organisms and therefore originate in areas favouring biological activity i.e. in shallow and warm seas in areas with little to no clastic input. In present day Earth conditions these would be primarily areas limited to ±40 latitude |
| Cretaceous | A geologic period that extends from about c.145 Mya (million years ago) to 65 Mya |
| CSR | Corporate Social Responsibility |
| Development well | A development well is drilled within the proved area of an oil or gas reservoir for the purpose of producing hydrocarbons |
| E&P | Exploration and production |
| Exploration well | An exploration well is drilled to find and test potential oil or gas accumulations in an unproved area |
| Formation | Used to describe a particular sequence of rocks of similar character recognizable over distance. Also an oil industry term used to describe a particular layer being tested for oil and gas |
| Fracture | A break in the rock that can serve as both a migration pathway and a reservoir for gas, oil and water |
| Graben | A fault bonded structural feature in the sub-surface resulting from extension. It may serve as a site for thick accumulation of hydrocarbon prospective rocks |
| HSE | Health, Safety and Environment |
| Hydrocarbon | Any liquid or gas made up of an appreciable volume of combustible organic compounds of hydrogen and carbon, such as any of those that are the chief components of petroleum and natural gas. |
| Karst | The topography that describes the erosion surfaces and caves that typically develop due to the solubility of carbonate rocks in dilute acidic groundwater |
| km2 | Square kilometres |
| Jurassic | A geologic period that extends from about c.200 Mya (million years ago) to 145 |
| mcf | Thousand cubic feet of gas |
| mcf/d | Thousand cubic feet of gas per day |
| mmbbl | Millions of barrels of oil |
| mmboe | Millions of barrels of oil equivalent |
| mmcf/d | Millions of cubic feet of gas per day |
| mmstb | Millions of stock tank barrels |
| NGLs | Natural Gas Liquids |
| NGO | Non-governmental organisation |
| Operator | Runs the day to day hydrocarbon exploration and production programme on behalf of the working interest holders in the project |
| Permeable | A rock that allows fluid to pass through it easily is said to be permeable |
| Petroleum | A flammable mixture of gaseous, liquid, and solid hydrocarbons that occurs naturally beneath the Earth's surface capable of being separated into various fractions |
| Platform | A continental area covered by relatively flat or gently tilted, sedimentary strata |
| Prospective Resources | An estimate of the potential oil and gas volumes thought to be present in an undrilled area. |
| PSC | Production Sharing Contract |
| psi | Pounds per square inch (pressure) |
| Reef | A build-up of carbonate rocks in tropical waters developed through biotic processes dominated by corals and calcareous algae |
| Reservoir | A rock formation with sufficient holes (porosity) to hold and store oil until it is discovered and sufficient permeability to allow the oil to be produced economically. A reservoir rock hosts the hydrocarbon accumulation in the subsurface and may consist of any number of rock types (although it is often sandstone). Also includes permeable and porous fractured rock and coal seams |
| Section | A stratigraphic sequence encountered in a well |
| Seismic | The seismic process records the time taken for a sound wave to travel from the surface of the earth to a sub-surface rock layer and then back again. The data collected can be processed to provide a pictorial representation of the sub-surface rock layers and is used extensively in hydrocarbon exploration and production. In a 2D seismic survey, several seismic lines are recorded to yield individual cross-sections. In a 3D seismic survey, multiple closely spaced seismic lines are recorded and the high density of cross sections are interpolated to yield detailed subsurface maps on which exploration prospects can be delineated. |
| Stock tank barrel | A barrel of oil measured at standard temperature (60o F) and pressure (14.7 psi) |
| STOIIP | Stock tank oil initially-in-place |
| Tertiary | A geologic period that extends from about c.65 Mya (million years ago) to beginning of the last ice age. |
| WI | Working interest |
