Learning How Reservoirs Work to Improve Oil Reserve Production

Now that we have so much information on how to find reservoirs that may hold potential oil and natural gas stores, it is now up to scientists to understand how the reservoir actually works. 3D imaging helps us determine the structure of the reservoir by identifying how it is encased by surrounding rock formations. 4D imaging is helping geophysicists understand better how the reserve may shift over time within the reservoir. However the process of hydraulic fractures is being given a closer look because of its beneficial properties to the overall process.

According to the website worldoil.com, a new simulation provides some consolation to those wanting to know more before they hit the ground running…I mean, drilling. In combination with hydrofracs and horizontal drilling, many wells can now be reached that were “stranded” or simply more costly to reach by vertical drilling alone. You would think that an increase in productivity with the wells would mean increased costs as well, but really it’s the opposite. Costs are driven by the circumstances surrounding each well, and specifically its location. Now that horizontal drilling and hydrofracs are commonly used, location isn’t an issue.

With this brand new simulation model, engineers can better understand the mechanics of extraction using hydrofracking. Understanding such measurements such as Ultimate Recovery (UR), aperture, and half-length is crucial to determining the best equation for extraction. Once the most economical and efficient hydrofrac is determined, this can be tested to see how well the process actually fits the data.

Flow dynamics helps describe why hydrofracs are necessary depending on the flow of the reservoir. The following table describes which type of flow requires which type of hydrofrac:

Type of Flow	Type of Hydrofrac
Linear	Transverse
Radial	Pancake

So much more can be learned of how hydrofracs behave when reaching reservoirs, but it depends upon the methods implemented to produce the simulation. Here is a current list of hydrofrac simulation modeling methods:

• Single porosity
• Dual porosity
• MNC
• Dual permeability

The flow dynamics of the well will determine which types of modeling are best within the simulation. Once more studies can be conducted on hydrofracs and their impact upon reservoirs, quantifying the most successful outcomes is the next logical step. This will lead to greater productivity (greater Ultimate Recovery) when extracting petroleum.