Experimental Evaluation Of Fracturing Fluid Interaction With Tight Reservoir Rocks And Propped Fractures

U. Ahmed; A.S. Abou-Sayed; A.H. Jones
Presented at: Symposium on Low Permeability Gas Reservoirs, Denver, Colorado, May 1979.

Abstract

Prediction of gas well production after a Massive Hydraulic Fracture (MHF) treatment is essential for economic assessment of the planned stimulation. Present accepted techniques of predicting the Present accepted techniques of predicting the increase in production (stimulation ratio) are based on the estimated fracture dimension, well and reservoir properties. Fracturing fluid damage is not considered. This study demonstrates that when fracturing fluid damage is included in the stimulation ratio calculations, good agreement with actual post fracturing production can be achieved. Laboratory experiments at simulated in situ conditions (stress, temperature, saturation and fracturing treatment procedure) on actual core samples were performed procedure) on actual core samples were performed to assess fracturing fluid damage to both the matrix permeability and propped fracture conductivity; permeability and propped fracture conductivity; damage was found to be site specific. Laboratory data on cores from unconventional gas reservoirs in both the Eastern and Western parts of the U.S. are presented. The observed damage is identified and explained. Specific examples are presented and predicted production compared with postfracturing flow. Good agreement was obtained. postfracturing flow. Good agreement was obtained