# Oil Initially In Place (OIIP)

## What is ‘Oil Initially In Place – OIIP’

The amount of crude first estimated to be in a reservoir. Oil initially in place differs from oil reserves, as OIIP refers to the total amount of oil that is potentially in a reservoir and not the amount of oil that can be recovered. Calculating OIIP requires engineers to determine how porous the rock surrounding the oil is, how high water saturation might be and the net rock volume of the reservoir.

## Explaining ‘Oil Initially In Place – OIIP’

Determining oil initially in place is one of the major components undertaken by analysts determining the economics of oil field development. Oil operations do not typically recover the entire amount of oil that a reservoir may have available, meaning that not all fields will be economical unless oil prices warrant the effort.

## Oil Initially In Place (oiip) FAQ

#### How do you find the original oil in place?

Calculating oil volume in place 7758= conversion factor from acre-ft to bblbarrels. A = area of reservoir, acres from map data. h = thickness of reservoir pay, ft. Φ = porosity (decimal, not percent)Sw = water saturation (decimal, not percent)

#### What is Oiip?

Oil initially in place (OIIP) is the amount of crude oil initially estimated to be in a reservoir. Oil initially in place differs from oil reserves, as OIIP refers to the total amount of oil potentially in a reservoir and not the amount recoverable.

#### What is oil recovery factor?

The recoverable amount of hydrocarbon initially in place, usually expressed as a percentage. The recovery factor is a function of the displacement mechanism. Enhanced oil recovery aims to increase the recovery factor.

#### How can oil be recovered from a reservoir?

Supply energy to the reservoir to extract additional oil. Introduce this extra energy by injecting gas or water or supplying heat. This stage of production is generally referred to as secondary recovery. Eventually the natural drive energy is dissipated.

#### How can I improve my oil recovery?

Secondary recovery uses water and gas injection, displacing the oil and driving it to the surface. According to the US Department of Energy, these two methods of production can leave up to 75% of the oil in the well. The way to further increase oil production is through the tertiary recovery method or EOR.

#### What does EOR mean in oil and gas?

It means Enhanced Oil Recovery.

#### How much oil is typically still left in the reservoir?

After secondary recovery, around 30% of the oil in the reservoir has been recovered and around 70% remains in the ground, and so an operator can consider tertiary recovery (known as EOR).