What term describes processes to increase the amount of oil removed from a reservoir, typically by injecting a liquid or gas?

What term describes processes to increase the amount of oil removed from a reservoir, typically by injecting a liquid or gas?

• A. Primary recovery
• B. Secondary recovery
• C. Enhanced Oil Recovery (EOR)
• D. Tertiary recovery

Answer: (C)

This question tests understanding of how oil recovery stages are defined by the methods used to extract more oil. After a reservoir’s natural energy starts to fade and primary production tapers off, additional recovery methods involve injecting fluids to improve displacement of oil. Enhanced Oil Recovery (EOR) is the umbrella term for these advanced techniques that aim to pull out more oil than primary or standard secondary methods can achieve. It includes injecting liquids or gases to alter reservoir conditions, reduce oil viscosity, or improve sweep efficiency, so you can recover a larger portion of the oil in place. Water injection used in secondary recovery is part of the broader recovery strategy, but EOR specifically covers the methods used to boost recovery beyond that baseline, often involving more specialized injections such as gas floods, chemical flooding, or steam. Therefore, the correct term describing these processes is Enhanced Oil Recovery.

This question tests understanding of how oil recovery stages are defined by the methods used to extract more oil. After a reservoir’s natural energy starts to fade and primary production tapers off, additional recovery methods involve injecting fluids to improve displacement of oil. Enhanced Oil Recovery (EOR) is the umbrella term for these advanced techniques that aim to pull out more oil than primary or standard secondary methods can achieve. It includes injecting liquids or gases to alter reservoir conditions, reduce oil viscosity, or improve sweep efficiency, so you can recover a larger portion of the oil in place. Water injection used in secondary recovery is part of the broader recovery strategy, but EOR specifically covers the methods used to boost recovery beyond that baseline, often involving more specialized injections such as gas floods, chemical flooding, or steam. Therefore, the correct term describing these processes is Enhanced Oil Recovery.