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Consult your investment advisor or tax advisor concerning the current tax laws and effects on your personal tax situation. Products made from petroleum With Over products and counting, petroleum continues to be a crucial requirement for all consumers.
Products made from crude oil After crude oil is removed from the ground, it is sent to a refinery where different parts of the crude oil are separated into useable petroleum products.
Which in turn yields a remaining oil supply of only about years, if current demand remain static. Petroleum is a fossil fuel derived from ancient fossilized organic materials, such as zooplankton and algae. Vast quantities of these remains settled to sea or lake bottoms, mixing with sediments and being buried under anoxic conditions.
As further layers settled to the sea or lake bed, intense heat and pressure build up in the lower regions. This process caused the organic matter to change, first into a waxy material known as kerogen, which is found in various oil shales around the world, and then with more heat into liquid and gaseous hydrocarbons via a process known as catagenesis.
There were certain warm nutrient-rich environments such as the Gulf of Mexico and the ancient Tethys Sea where the large amounts of organic material falling to the ocean floor exceeded the rate at which it could decompose. This resulted in large masses of organic material being buried under subsequent deposits such as shale formed from mud. This massive organic deposit later became heated and transformed under pressure into oil.
Sometimes, oil formed at extreme depths may migrate and become trapped at a much shallower level. The Athabasca Oil Sands are one example of this. An alternative mechanism was proposed by Russian scientists in the mids, the Abiogenic petroleum origin, but this is contradicted by the geological and geochemical evidence. Three conditions must be present for oil reservoirs to form: a source rock rich in hydrocarbon material buried deep enough for subterranean heat to cook it into oil, a porous and permeable reservoir rock for it to accumulate in, and a cap rock seal or other mechanism that prevents it from escaping to the surface.
Within these reservoirs, fluids will typically organize themselves like a three-layer cake with a layer of water below the oil layer and a layer of gas above it, although the different layers vary in size between reservoirs.
Because most hydrocarbons are less dense than rock or water, they often migrate upward through adjacent rock layers until either reaching the surface or becoming trapped within porous rocks known as reservoirs by impermeable rocks above. However, the process is influenced by underground water flows, causing oil to migrate hundreds of kilometres horizontally or even short distances downward before becoming trapped in a reservoir. When hydrocarbons are concentrated in a trap, an oil field forms, from which the liquid can be extracted by drilling and pumping.
The reactions that produce oil and natural gas are often modeled as first order breakdown reactions, where hydrocarbons are broken down to oil and natural gas by a set of parallel reactions, and oil eventually breaks down to natural gas by another set of reactions.
The latter set is regularly used in petrochemical plants and oil refineries. This creates an organic-rich mud. This mud can only form in still water environments. This step is shown in Figure 1, panel A. This mud cannot be exposed to too much oxygen , or else the organic matter in the mud would be decomposed by bacteria and disappear quickly.
Therefore environments where oil can form are known as anoxic environments. Before this organic matter is destroyed, it is buried by more sediment and lithifies becomes sedimentary rock , creating organic shale. This step is shown in Figure 1, panel B. Burying material underwater is an easy way to create an anoxic environment because the atmosphere is not interacting with the decaying matter. If this shale is buried between 2 and 4 kilometers , its temperature increases due to its location in the Earths interior.
This increasing pressure and temperature of the shale transforms it into a waxy material known as kerogen. Shale that contains this material is known as oil shale. At temperatures higher than this, only natural gas literally a gas that's a hydrocarbon or graphite is formed. There are also large reservoirs in sand that was deposited on alluvial plains during the Triassic Period the Snorre field , in shallow seas in the Late Jurassic the Troll field and as subsea fans during the Paleogene Period the Balder field.
In the southern part of the North Sea, thick layers of chalk composed of microscopic calcareous skeletons of plants and animals form an important reservoir rock, as in the Ekofisk Field. Download as image PNG. Mudrocks and other impermeable deposits influence migration routes from the source rock to the reservoir. In addition, impermeable rock has to be present to stop petroleum escaping from reservoir rock.
Impermeable rock that forms a seal over reservoir rocks is called cap rock. In addition, the configuration of the reservoir rocks must be such that the oil collects in a trap. If there is a suitable combination of source rock, reservoir rock, cap rock and a trap in an area, recoverable oil and gas deposits may be discovered there.
The illustrated elements have to be in place in order to find producible oil and gas reservoirs Source: The Norwegian Petroleum Directorate.
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