We don't often think about where the petrol comes from though we spend so many hours driving. Moreover, we don't think about how it is transformed from crude oil and taken from the refinery and brought to our service stations. Read on for the basics.
Instructions
1. It takes thousands if not millions of years for oil molecules to form. Basically the remains of creatures that existed millions of years ago chemically change and become compressed in to sedimentary rock.
2. Over time, with pressure from the sea or ocean and the transferring of silt and sand, those layers of sediment became even more compressed. Further chemical changes take place to turn the remains of those creatures in to combinations of hydrogen and carbon. Remember, this process takes hundreds of thousands of years and is reliant upon heat, pressure and time.
Eventually, the hydrogen and carbon atoms begin to change in composition and given all the right ingredients like changes in the earth's movement, changes in the rock type and movements in the rock itself.
3. How oil is found:
Geologic Surveyors use a number of "tests" to determine where oil may be hiding in areas of "sedimentary" rock. This is essentially any rock, formed over time, made of sediment. Surveyors use specific tests like looking for source rock, reservoir rock, cap rock, traps and the correct sequence of geologic events. They determine how long the organic materials may have been trapped in the rocks, allowing hydrocarbons to form.
4. Once the surveying begins, surveyors and producers of oil or petrol are only looking for the "possibility" that the correct hydrocarbons are in place and digging can begin. With off-shore drill sites, when drilling begins, pumps are used to extract oil and gas and pump them both up in to a reservoir. When the oil and gas hit the pumps, they are both bubbling and have to be separated. One pipeline will transport gas, and the other, the crude oil.
That reservoir contains the oil that will be transported by pipeline back to the mainland refinery.
