In natural gas production, what is the purpose of injecting sand into fractures?

In natural gas production, what is the purpose of injecting sand into fractures?

• A. To seal fractures
• B. To keep fractures open
• C. To increase temperature
• D. To reduce permeability

Answer: (B)

In hydraulic fracturing, the sand acts as a proppant. After the fractures are created, the rock would tend to close as soon as the fracturing pressure drops, because the rock is elastic and the pore pressure decreases. The sand grains lodge within the fracture voids and form a proppant pack that resists this closure, keeping the fracture apertures open. With the fractures held open, the connected fracture network remains permeable, allowing natural gas to flow more easily from the reservoir to the well. That’s why the purpose is to keep fractures open. Sand isn’t used to seal fractures, it doesn’t raise temperature, and it doesn’t reduce permeability—in fact, it increases the effective permeability by maintaining open pathways.

In hydraulic fracturing, the sand acts as a proppant. After the fractures are created, the rock would tend to close as soon as the fracturing pressure drops, because the rock is elastic and the pore pressure decreases. The sand grains lodge within the fracture voids and form a proppant pack that resists this closure, keeping the fracture apertures open. With the fractures held open, the connected fracture network remains permeable, allowing natural gas to flow more easily from the reservoir to the well.

That’s why the purpose is to keep fractures open. Sand isn’t used to seal fractures, it doesn’t raise temperature, and it doesn’t reduce permeability—in fact, it increases the effective permeability by maintaining open pathways.