OAPEC (Organization of Arab Petroleum Exporting Countries)
Organization of Arab Petroleum Exporting Countries. Coordinates petroleum policies of major oil-producing Arab states. In early 1987 membership included Algeria, Bahrain, Egypt, Iraq, Kuwait, Libya, Qatar, Saudi Arabia, Syria, and the United Arab Emirates.

The salt water surrounding the great land masses. The land masses divide the ocean (71% of global earth surface) into several distinct portions, each of which also is called an ocean. The oceans include the Pacific Ocean, the Atlantic Ocean, the Indian Ocean, and the Arctic Ocean.

Ocean dumping
Deliberate disposal of hazardous wastes at sea from vessels, aircraft, platforms or other human-made structures. It includes ocean incineration and disposal into the seabed and sub-seabed.

Ocean Thermal Energy Conversion (OTEC)
Electricity generation by making use of the temperature difference (as much as 20°C, or 68°F, in the tropics) between the top and bottom layers of the ocean to convert a fluid to vapor, which in turn powers a turbine generator. Low efficiency and saltwater corrosion are two current technical problems with the implementation of OTEC.

The major goals of oceanography are to understand the geologic and geochemical processes involved in the evolution and alteration of the ocean and its basin, to evaluate the interaction of the ocean and the atmosphere so that greater knowledge of climatic variations can be attained, and to describe how the biological productivity in the sea is controlled.

(see Octane Number)

Octane Number (O.N.)
A measure of the resistance of a fuel to pre-ignition (“knock”) when burned in an internal combustion engine. The higher the octane number, the higher the resistance to engine knock. Octane numbers come in two forms: Research octane number reflects fuel performance under moderate driving conditions, while the tests for Motor octane number reflect high speed driving conditions. Tests for both numbers are in fact performed in the laboratory.

Odorizer – Odorant
A material that has a distinctive, sometimes unpleasant, odour and that may be added to odourless materials to give warning of their presence (the term “odorizer” is also used for the latter application). In most areas the addition of an odorant to natural gas (to avoid the danger of explosions resulting from undetected leaks) is mandatory.

Airborne chemicals emanating from water, objects, flowers or fragrance that stimulate the olfactory system.

The term offshore indicates a portion of open sea and, by induction, the activities carried out in such area, while onshore refers to land operations.

Oil fields in sub-sea areas at some distance from the coast. Estimates place 45% of world petroleum and gas reserves in offshore areas. The term “deep off-shore” is used to designate fields lying at depths greater than 200 meters below sea level. (source: ENI)

Oil dispersants
Chemicals that are used to break down spilled oil (see oil spill) into small droplets (see surfactants).

Oil recovery processes
A procedure whereby petroleum is removed from a petroleum reservoir through wells. There are three kinds of oil recovery processes: Primary recovery: Oil recovery utilizing only naturally occurring forces or mechanical or physical pumping methods. Secondary recovery: Oil recovery resulting from injection of water or natural gas into a petroleum reservoir. Enhanced recovery: recovery techniques designed to extract more hydrocarbons from a reservoir by physical, chemical or thermal means.

Oil slick
A layer of oil floating on the surface of water.

Oil spill dispersion
The breaking up of an oil slick (see) into small droplets that are mixed into the water column by breaking waves and other sea surface turbulence.

Oil spills
An accidental or intentional discharge of oil which reaches bodies of water. Can be controlled by chemical dispersion, combustion, mechanical containment, and/or adsorption. Spills from tanks and pipe- lines can also occur away from water bodies, contaminating the soil, getting into sewer systems and threat- ening underground water sources.

Oil tanker
A ship designed for the carriage of oil in bulk, her cargo space consisting of several or many tanks. Tankers load their cargo by gravity from the shore or by shore pumps and discharge using their own pumps.

Any of a large class of substances typically unctuous, viscous, combustible, liquid at ordinary temperatures, and soluble in ether or alcohol but not in water: used for anointing, perfuming, lubricating, illuminating, heating, etc.

Oleophilic fertilizers
Oleophilic Having a strong affinity for oils; oleophilic materials absorb or stick to oils. Oleophilic skimmer A skimmer that uses a specially treated surface that allows oil, but not water to stick to it (oleophilic means oil loving). These surfaces are then scraped of all oil which is then transferred to a storage area.

Referring to a submarine zone slightly lighted.

OME Observatoire Méditerranéen de l’Energie
The Observatoire Méditerranéen de l’Energie (OME) is a non-profit oriented organisation whose main objective is to promote the co-operation between the major energy companies operating in the Mediterranean basin. The Association is a center of studies and information on energy in the Mediterranean area as well as a pole of reflection and a permanent meeting forum between its members.The OME has been created in 1988 within the “Centre d’Energétique” of the Ecole des Mines de Paris (a prestigious French engineering school) with the support from the European Commission and particularly from the Directorate General Energy. In 1991, at the request of various interested companies, the OME became independent and was transformed into an Association of major Mediterranean energy companies.

Open pit
The area from which ore and waste rock are removed.

A company, organisation or person with the legal authority to drill wells and extract hydrocarbons. A drilling contractor may be employed to undertake the drilling itself. The operator is often part of a consortium, and acts on its behalf. See Majors and Independent.

Optimal pollution level
The pollution level that maximizes net social benefits.

The path of a satellite, planet, or heavenly body around another, larger, body in space. For example, the Earth is in orbit around the Sun. The Moon is in orbit around the Earth. Scientists since the time of Johann Kepler have known that orbits are ellipses. The orbits of the Earth and of eight of the other planets in the solar system are ellipses that are very nearly circular.

Organic waste
Organic material that originally came from a plant and or an animal and can decompose naturally. Organic waste includes garden and kitchen waste, food process wastes, and sewage sludge. See also compost.

Any living thing. Organisms include humans, animals, plants, bacteria, protozoa and fungi.

Organization for Economic Cooperation and Development (OECD)
An international organisation which helps governments tackle the economic, social and governance challenges of a globalised economy. Established members are: Australia, Austria, Belgium, Canada, Denmark, Finland, Iceland, Italy, Japan, Luxemburg, Mexico (since 1994), Norway, New Zeland, Holland, France, Germany, UK, Greece, Ireland, Portugal, Spain, USA, Sweden, Swiss, Turkey. Headquarters in Paris.

Organization of Arab Petroleum Exporting Countries (OAPEC)
Organization of Arab Petroleum Exporting Countries founded in 1968 for cooperation in economic and petroleum affairs. Headquarters in Kuwait. Among its members: Algeria, Bahrein, Iraq, Saudi Arabia, United Arab Emirates.

Organization of Petroleum Exporting Countries
Organization of Petroleum Exporting Countries. Formed in 1960, its member countries are Algeria, Ecuador, Gabon, Indonesia, Iran, Iraq, Kuwait, Libya, Nigeria, Qatar, Saudi Arabia, United Arab Emirates and Venezuela. They choose to collaborate in order to manage the exportation of their crude oil to the rest of the world. Because of their ability to adjust production levels, they possess a great deal of influence on the price of oil. Headquarters is in Vienna, Austria.

A major episode of plate tectonic activity in which lithospheric plates collide and produce mountain belts, in some cases including the formation of subduction zones and igneous activity. Thrust faults and folds are typical geological structures seen in areas of orogeny.

The female part of a flower that contains the ovules. Fertilized ovules (see) develop into mature seeds.

The growing of water over the confines of a stream or other body of water.

An ovule is the female reproductive cell of flowering plants and cone-bearing plants. After the ovule is fertilized by the male pollen, the ovule becomes a seed.

A very qualitative term which includes any and all trace gases which have a greater oxidation potential than oxygen (for example ozone, peroxyacetyl nitrate, hydrogen peroxide, organic peroxides, NO3, etc.).

A reaction in which there is a loss of electrons; increase in oxidation number.

Oxidation-Reduction (Redox Reaction)
A reaction in which electrons are transferred between species or in which atoms change their oxidation number (see). Oxidation Number or Oxidation State The charge on an atom in a compound or molecule.

A compound in which oxygen is bonded to one or more electropositive atoms.

A colourless odourless highly reactive gaseous element: the most abundant element in the earth’s crust. Symbol: 0. Atomic number: 8. Its one of the constituents of water, organic matter, and many other chemicals. Oxygen gas (O2), composed of two oxygen atoms, is needed for respiration and is produced by photosynthesis.

Substances which increase the amount of oxygen in gasoline, and help it burn more cleanly. Ethanol and Methyl Tertiary Butyl Ether (MTBE) are common oxygenates.

Pungent, colourless, toxic gas that contains three atoms of oxygen in each molecule. It occurs naturally at a concentration of about 0.01 parts per million (p.p.m.) of air. Levels of 0.1 p.p.m. are considered to be toxic. A)Stratospheric Ozone (“good ozone”): In the stratosphere (the atmospheric layer beginning 7 to 10 miles above the earth), ozone is a form of oxygen found naturally which provides a protective layer shielding the earth from ultraviolet radiation’s harmful effects on humans and the environment. B)Ground Level Ozone (“bad ozone”): Ozone produced near the earth’s surface through complex chemical reactions of nitrogen oxides, hydrocarbons, and sunlight. Ground level ozone is the primary component of smog and is harmful to humans and the environment.

Ozone hole
Stratospheric ozone depletion over the Antarctic. The hole appears every southern hemisphere spring (August to October) before disappearing during the summer months (December / January).

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