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Dukes Wood is the UKs First Major oil discovery
Britain's first major onshore oil discovery, occurred at the Eakring and Dukes Wood oil fields.
In 1939 the D’Arcy exploration company, a subsidiary of Anglo/Iranian Oil, now BP, discovered oil near the town of Eakring. Other wells were soon drilled in the nearby Duke’s Wood and by the start of the Second World War 1,200 people were employed in oil exploration and drilling. By the end of the war some 170 “nodding donkeys”, one to every 2.5 acres, were each producing an average of 64 barrels a day. Both fields were eventually depleted and shut down in 1989, and BP donated the site to the Nottinghamshire Trust for Nature Conservation together with a grant for upkeep.
What is Oil?
Oil is a generic term for fluids that are not miscible with water. The name comes from Latin oleum for olive oil. Crude oil consists of a mixture of petroleum liquids and gases (together with associated impurities) pumped out of the ground through oil wells. Petroleum (from Latin petrus–rock and oleum–oil) or mineral oil. It can be shortened to the prefix petro-, as in "petrodiesel". Petroleum is a thick, dark brown or greenish inflammable liquid, which, at certain points, exists in the upper strata of Earth's crust. It consists of a complex mixture of various hydrocarbons, largely of the methane series, but may vary much in appearance, composition, and properties. In chemistry, a hydrocarbon is an organic compound consisting only of carbon and hydrogen. They all consist of carbon backbone and atoms of hydrogen attached to that backbone. The simplest hydrocarbon, methane is a gas with a chemical formula of CH4. Strictly speaking, petroleum consists entirely of aliphatic hydrocarbons, those composed of nothing but hydrogen and carbon. The four lightest hydrocarbons -- CH4 (methane), C2H6 (ethane), C3H8 (propane) and C4H10 (butane) -- are all gases, boiling at -107°C, -67°C, -43°C, and -18°C, respectively (-161°, -88°, -46°, and -1° degrees F). The chains in the C5-7 range are all light, easily vaporized, clear naphthas. They are used as solvents, dry cleaning fluids, and other quick-drying products. The chains from C6H14 through to C12H26 are blended together and used for Petrol (gasoline). Kerosene is made up of chains in the C10 to C15 range, followed by diesel fuel/heating oil (C10 to C20) and heavier fuel oils as the ones used in ship engines. These petroleum compounds are all liquid at room temperature. Lubricating oils and semi-solid greases (including Vaseline®) range from C16 up to C20. Chains above C20 form solids, starting with paraffin wax, then tar and asphaltic bitumen.
Formation
Millions of years ago much of the earth was covered by seas and swamps. As microscopic animals and plants in these seas died, their remains were deposited in the sea bed, they mixed with rock materials eroded from higher ground. Gradually, sediments many thousands of feet thick, built up and became compressed to form sedimentary rocks such as sandstone and limestone. Because of the lack of oxygen, the small organisms did not decay but were transformed by heat and high pressure into oil and gas. This biological material in rocks starts off largely as a waxy material known as kerogen. As more new rocks formed above, gravity, capillary action and water pressure forced the oil and gas out of this source rock and upwards through porous rocks. If further upward movement was eventually stopped by rock layer and if a side ways movement was prevented by a fold or fault in the earth's surface, then oil and gas are trapped in a reservoir. This is not an underground lake, as the name suggests: oil and gas are held in the pores between grains the same as water is held in a sponge. A few scientists, notably Thomas Gold, have suggested other, abiogenic, theories for the origins of crude oil.
Much more detail can be obtained from the Dukes Wood Oil Museum.
To claim this EarthCache, you should:
1) post a photo of you at the co-ordinates
2) email me the date which the first oil well was spudded
3) tell me how many oil pumps (nodding Donkeys) you find in the wood
4) Tell me the number of the deepest oil well found here and its depth
Additional Hints
(No hints available.)