As more gas wells have been completed in East Texas on 160 acre spacing, fracturing down casing has become more prevalent as the best way to stimulate these wells. Field trends have been toward higher sand concentrations. Most wells were fractured earlier through 2 7/8″ tubing with maximum concentrations of 3 lbs./gal. 20-40 Mesh Sand. However, as wells were produced, it became evident that longer fractures and higher flow capacities were needed. The casing fracturing technique permitted higher pumping rates which allowed higher sand concentrations to be placed. These began to be placed at 4 lbs. and 5 lbs./gal. and have now successfully been placed at concentrations in the 7 lbs. to 10 lbs./gal. range. Recently several jobs have been placed at 15 lbs./gal.

These higher sand concentrations as compared to a lower sand concentration in an equal predicted propped fracture length seem to be giving improved clean-up of fracture fluids and longer stabilized flow rates. This improved clean-up is probably due to the higher fracture flow capacity to a multi-phase fluid which is present in the fractures immediately after fracturing. The higher fracture flow capacity also would be maintained even with fines and residue from treatment fluids thus yielding the better stabilized flow rates.

You can access this article if you purchase or spend a download.