Let's talk about the petroleum reservoir

10 months ago

An oil reservoir must be considered as a reservoir that stores a mineral resource, in this case it stores oil and/or natural gas, the oil reservoir has the ideal geological conditions to accumulate oil and/or natural gas in subsoil formations whose rocks are porous and permeable, this condition of porosity and permeability may not be present, so then the subsoil rocks must be fractured in case they have low porosity, since their permeability may increase due to their fracture.

An oil reservoir not only has its influence as a source rock that stores oil, but also has its origin as that geological structure that influenced the formation of oil and/or natural gas, since oil reservoirs were formed when vegetable and animal matter decomposed and kerogen was created, oil simply migrates from the source rock to the storage rock due to high pressures and high temperatures and also to the geological conditions that allow such accumulation, migration and final deposit or entrapment.

Is an oil field the same as an oil field?

The oil field is the unit of accumulation of oil, while an oil field contemplates an entire area of accumulation of oil and natural gas, so it can be stated that an oil field can have multiple oil fields, so it can be stated that an oil field can be commercially exploited and have a production associated with such oil field.

Everything explained above leads us to conclude that an oil field is not the same as an oil field, since the oil field contemplates several oil fields that may be in production.

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What are the essential geological factors that must be met for oil to be trapped?

The first important thing to understand is that if there is no geological trap, oil will continue to migrate, therefore there will be no oil reservoirs (deposits).

More important than explaining the formation process of a geological trap is to name some of its classifications, there are three types of traps, but the most common in the oil industry are the structural traps and stratigraphic traps.

In the following images we can see two cases of structural traps:

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The first image is of a structural trap of the anticline type, in an anticline you can see how the strata are folded causing the oil to trap and form the oil reservoir.

The second image is of a structural fault trap, this type of trap is characterized because there are two types of rocks, one permeable and the other impermeable, a slip occurs in the fault plane causing the permeable reservoir rock to join with the impermeable reservoir rock, making possible the accumulation of oil and forming a new reservoir product of this type of geological trap.

Conclusion

An oil field is a geological unit that distinguishes the origin, migration and accumulation of oil and where there is a convergence of geological factors that make these oil fields can be exploited commercially.

Logically, for oilfields to exist there must be some geological conditions called oil traps, among which are the so-called structural traps (faults and anticlines), as well as the so-called stratigraphic traps, however, the importance from the engineering point of view lies in knowing how to diagnose the possible geological environments that favor the accumulation of oil and also that the corresponding exploration studies can be carried out to know the type of trap that forms the oil field being studied, and with all this data apply the best techniques in future drilling operations to be exploited in an optimized way that oil field.