Time-Dependent Proppant Pack Conductivity and Hydraulic Fracture Design

Proppant selection requires an understanding of whether greater crush resistance translates into better flow performance under sustained loading. Short-term crush tests were compared with conductivity and permeability measurements over 60 h at 54.3 MPa and 86 °C for nominal 16/20 and 20/40 mesh fractions of a polymer-coated magnesia–quartz ceramic proppant. At 68.95 MPa, the crushed fraction was 8.88% for 16/20 and 2.27% for 20/40. After 60 h, the packs retained 81.4% and 77.7% of their initial conductivity, respectively, and 77.9% and 80.7% of their initial permeability. The greater crush resistance and permeability retention of the 20/40 fraction therefore did not extend to conductivity retention. Because conductivity also depends on pack thickness, permeability retention alone does not determine conductivity retention. Treating initial conductivity as a constant overestimates its value at 60 h by 22.9% for 16/20 and 28.7% for 20/40. A separate model recalculation using recorded treatment data illustrates how operating conditions affect predicted fracture geometry and spatially averaged conductivity.