The formula for the production gas oil ratio (GOR) is GOR = (metered well gas volume during the test + the GIS volume during the test) / measured oil volume during the test.
Understanding the Gas Oil Ratio (GOR) Formula
The Gas Oil Ratio (GOR) is a crucial metric in the oil and gas industry, representing the volume of gas produced per unit volume of oil produced. It is typically measured during a well test or over a period of production. Based on the provided reference, the formula calculates the GOR using specific measured volumes during a testing period.
Components of the GOR Formula
According to the reference, the GOR calculation involves three key components measured during a specific test period:
- Metered Well Gas Volume: This is the volume of gas that is directly measured coming from the well during the test.
- GIS Volume: The reference includes "the GIS volume during the test" in the numerator. While the exact definition of "GIS" in this context isn't explicitly provided, it is treated as a volume of gas (or a related fluid volume accounted for as gas) that needs to be added to the metered well gas. It is critical to understand what "GIS" represents within the specific context of the measurement procedure being referenced to apply the formula correctly. It could potentially refer to volumes accounted for separately but associated with the production stream, such as gas flared, vented, or used on-site that isn't captured by the main sales gas meter.
- Measured Oil Volume: This is the volume of oil that is measured during the same test period.
How the Formula Works
The formula calculates the total volume of gas produced (metered gas plus the GIS volume) and divides it by the volume of oil produced over the identical test period. This provides a ratio, often expressed in standard cubic feet per barrel (SCF/bbl) or cubic meters per cubic meter (m³/m³), indicating the volume of gas associated with each unit of oil produced.
Formula Breakdown
Here's a simple breakdown based strictly on the provided reference formula:
| Component | Description | Location in Formula |
|---|---|---|
| Metered Well Gas Volume | Volume of gas directly measured from the well during the test. | Numerator |
| GIS Volume | An additional volume (referred to as "GIS") measured during the test period. | Numerator |
| Measured Oil Volume | Volume of oil measured during the same test period. | Denominator |
Formula: GOR = (Metered Well Gas Volume + GIS Volume) / Measured Oil Volume
This formula is essential for:
- Evaluating well performance.
- Estimating reserves.
- Designing production facilities.
- Allocating production volumes.
Understanding each term in the formula is crucial for accurately calculating the GOR for a specific well or field.
