How oil is formed
Also known as “black gold” , oil is one of nature’s most desired resources and, at the same time, rejected by the world’s societies. And it is that having sources of oil is not always a sign of wealth. There are many advantages and disadvantages of oil, which are mainly focused on economic advantages for those who exploit the oil sources and environmental and social disadvantages for the regions that suffer such exploitation. There are many studies and analyzes that seek to know the availability of this fossil fuel in the world, some of which indicate that the “peak oil” has already been passed and that it is running out more and more quickly.
What is oil
Oil is considered worldwide as one of the most widely used fossil fuels in our day to day life. Despite its negative effects on the environment (both during its extraction and final deposition processes), the uses of oil by the world’s societies are multiple, but summarizing them we can indicate that they are:
- Fuel in the gasoline of vehicles, machinery and energy and thermal industries.
- Production of plastics in materials and fabrics to give rise to objects of all kinds.
Now that we know what oil is used for , let’s see what the nature of this compound is, that is, its chemical composition. Oil is mainly made up of carbon and hydrogen ( hydrocarbons ), which are stored at a high depth, having a characteristic oily liquid consistency. To better understand its uses and fuels of this type, we advise you to read this other post about What are fossil fuels and how they were formed .
In the next sections we will see more characteristics of oil, as well as its formation and extraction processes to know the details of this fossil fuel.
The origin of oil is one of the most surprising natural phenomena discovered by human beings. In summary, the oil formation process is as follows:
- For millions of years the decomposition of organic remains of living beings (both animals and plants) has been taking place, which were being deposited on the seabed and lake areas.
- These organic remains were buried under many meters of layers of earth and rocks.
- The pressure exerted by these layers caused the decomposition in a medium without oxygen (anaerobic) to be an oily, viscous liquid compound, with a higher density than water and a dark color: oil. In addition, natural gas also appears during this type of process .
Knowing how oil was formed has allowed us to discover more and more sources of oil around the world. In the next section we will see exactly where this fossil hydrocarbon is most likely to be found.
Did you know that oil was already used in times of the Roman and Egyptian civilizations? However, at that time they did not have the machinery and technology necessary to access oil reserves located deeper, sometimes being located up to 5,000 meters deep.
As we have seen in the previous sections, given the chemical composition and formation of oil, it is essential to have large sources of organic matter and water resources which are deep and subject to high pressure. In this way, the ideal places for the formation of oil are, firstly, in the deep ocean , followed by coastal areas , as well as at the mouths of rivers, lakes and lagoons .
Some examples of countries and regions of the planet where large oil sources have been discovered are:
- Venezuela.
- Saudi Arabia.
- Canada.
- Iran.
- Russia.
- Nigeria.
- U.S.
- Brazil.
The methods of oil extraction depend, fundamentally, on the location of the oil source, that is, whether in land or marine areas. Due to the pressure exerted by sediments and rocks on oil sources , it tends to be expelled towards the earth’s surface through channels and cracks once these rocks are pierced, which act as a warehouse in which the oil accumulated during millions of years.
Thus, to know the subject well, it is also necessary to take into account these processes about the oil extraction process:
- Start by having the appropriate machinery and technology that allows, on the one hand, to carry out topographic and drilling studies of the terrain and, on the other hand, to extract and store the oil in pipes and special storage systems.
- This first oil is also called crude . This cannot be used directly, but needs to go through one or more refining processes (by fractional distillation), depending on the type of final oil to be obtained, such as liquefied petroleum gas resulting from mixing butane and propane. during oil refining.
- Other types of oil are classified according to their density (light-medium-heavy-extra heavy) or according to their composition (paraffinic, naphthenic or mixed base).
In addition, by applying different temperatures during the oil refining process, various oil derivatives are obtained , such as:
- Methane
- Butane
- The gas.
- Kerosene.
- Fuel oil.
- Paraffins.
- The tars.
