The Process of Forming Petroleum With Its Understanding and Components
Definition of Petroleum
Petroleum dubbed as black gold (petroleum from Latin petrus - less and oleum - oil) is a thick, dark brown, or burnt green liquid, which is in the upper layers of several areas in the earth's crust,
Petroleum consists of a complex mixture of various hydrocarbons, mostly alkane series, but varies in appearance, purity, and composition. Oil is extracted from oil wells in oil mines.
The location of these wells was obtained after going through a process of geological knowledge, sediment analysis, character and source structure, as well as various other knowledge. Then the oil is processed at the refinery and the results are broken down based on boiling points to produce various fuels,
ranging from gasoline and kerosene to asphalt and various chemical reagents needed to make plastics and medicines. Petroleum is used to produce various goods and materials needed by humans.
Process of Forming Earth's Oil
Earth's oil is the result of decomposition (decomposition) of animal and plant material in an area of subsidence (down) slowly. The area is usually in the form of a lagoon (lake) boundary along the coast or lake in the marsh on the mainland,
Sediment is deposited together with the material and the sedimentation speed must be fast enough so that at least a part of the organic material can be stored and buried well before decay occurs.
The geological time and place of deposition continue to sink deeper into the earth's surface, because of the increasing weight of the sediments and materials piled on it, or because of the tectonic forces that cause the effect of subsidence. Organic material sinks deeper so that it experiences increasingly high pressures and temperatures.
The process will cause chemical changes from these organic materials. The material change is the forerunner to the formation of a mixture of hydrocarbon materials whose composition is very complex, both hydrocarbons in the form of liquids or in the form of gases.
The increase in temperature to an average depth of the world around 20 - 55 degrees Celsius per kilometer. Disumatera alone can reach around 100 ° C / km. Whereas new oil habitats are formed at temperatures around 65 - 150 ° C, which are generally located at depths of 1.5 - 3 km. At a depth of 3-6 km the reservoir rock will be dominated by gas rather than oil. For deeper depths the temperature will be different to be higher so that the gas will be higher so that the gas will experience decomposition.
Usually petroleum is deposited in good porous sedimentary rocks which have a porosity value of 45% (so good reseroar). Because the longer the rock is deposited and buried in the material above, then the rock will be compacted and this can cause the value of porosity to decrease.
Oil, gas, and water will be stored or collected in the pore spaces of the porous rock. Due to gravitational pressure, the fluid moves in the rock slowly. Aid that can escape fluid is called permeable rock.
Petroleum is formed from the breakdown of organic compounds derived from the bodies of small organisms that lived in the sea / waters millions of years ago. The process is that these organisms will die, then settle to the bottom of the sedimentary basin to produce a sedimentary basin.
Then this sedimentary basin will gradually be buried by other rocks above it so that it will gradually fall down where the temperature and pressure increase so that the decomposition process and oil will be produced.
The oil produced by the Parent rocks has a lower density than water so that the oil moves upward through the porous hole, but most of the oil is trapped in non-porous rocks so drilling is needed.
Search for Miyak Bumi
The process of finding (exploration) of oil from the bowels of the earth is carried out by geologists. The modern way used by geologists to search for petroleum is by using satellite imagery and analyzing rock surfaces. After the geologist conducts a series of analyzes and states that in the location there is oil, the next task is taken over by the geophysicist.
Geophysicists study the physical properties of soil layers. Various methods are used in this stage to support the results obtained by geologists. The equipment used to search for petroleum is like Gravimetry (to measure the presence of oil flow due to slight differences in earth's gravity),
Magnetometry (to measure changes in magnetic fields due to oil flow), and Sniffers in the form of electronic devices used to detect hydrocarbon odors. The most commonly used is seismology.
Seismology can be used to find oil reserves both on land and at sea. The main part of seismology is the trigger of vibration and signal reception. There are vibration triggers such as Compressed-air gun (specifically used for offshore exploration), Thumper trucks (for exploration of oil on land), and explosives.
The sound or vibration produced by the Thumper truck emits a signal or sound wave, the signal will be reflected back by the boundaries between different layers of rock captured by the geophone, the data is then sent to the truck that functions as the control center.
By detecting these reflections, experts can draw a map of rock structures below the earth's surface to find oil reserves. If petroleum reserves are positive at a location, the drilling process will begin.
If the center of the petroleum is located offshore, the extraction can be done in 2 ways, namely:
If the distance of the oil center is close to the mainland, a pipeline is planted on the seabed and pumps the earth oil to land.
If the oil center is far from the mainland, a drilling rig will be built and then the results will be taken by the tanker to land