The rapid post-fracture production rate decline observed in both oil and gas wells is normally associated with loss of fracture conductivity, often attributed to invasion of formation fines into the proppant pack, loss of fracture width caused by proppant flowback, and fines derived from proppant crushing. However, recent studies have indicated that solid material generated from a geochemical process in the fracture face known as proppant diagenesis has considerable impact on proppant conductivity.

Although diagenesis is a slow geological process, lab tests show that proppant diagenesis can occur in fractions of a year. Post-fracture rapid production decline in high-temperature/high-stress wells seems to be the main symptom of proppant diagenesis. Recent lab tests have shown that the process can be prevented by isolating the direct contact proppant/formation through the use of hydrophobic materials.

The liquid resin systems (LRS), a specific type of hydrophobic material, have been used in the industry to prevent proppant flowback. The proppant is coated on-the-fly on location with a LRS. This technology has also proved to increase and sustain fracture conductivity over time. The production data presented in this paper comes from some tight-gas fields located at the Burgos Basin in north Mexico. The formation fractured is an intermediate/high-temperature and high-stress sandstone. The wells previously fractured in these fields historically had a rapid post-fracture production decline rate.

The wells successfully treated with LRS material show a significant production increase compared to untreated offset wells because of a substantial change of the conductivity of the fracture. Based on laboratory experiments on proppant diagenesis and field results, it has been observed that the proppant diagenesis protection treatment provided by the LRS significantly contributed to the production increase of the treated wells.

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