The type of conventional resource reservoir that we focus on is a high water saturation hydrocarbon reservoir, which demonstrates characteristics of both a conventional reservoir and a resource play. The reservoir is typically made of carbonate or deltaic sand deposits. In these reservoirs, the porosity and permeability are not well connected vertically in the formation, which restricts the movement of fluid vertically through the reservoir. However, these reservoirs have good horizontal permeability and porosity that usually extend over a large area. In addition, the permeability in both directions is often enhanced by numerous naturally occurring fracture systems.
These types of reservoirs are composed of hydrocarbon accumulations in strata that have “shows” of oil. They have water saturations of 35 to 99 percent. Although the reservoir is saturated with water, there are often significant hydrocarbons present and suspended within the reservoir by the hydrostatic pressure. Conventional resource reservoirs are located around and below the conventional reservoir, though they can exist independently. This zone is a continuous hydrocarbon system over a contiguous geographical area that can be very large. Conventional resource plays are regional in extent and exhibit low risk, with consistent results and predictable Estimated Ultimate Recoveries (EURs).
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