An analysis of over 500 treatments in the Mesaverde formation of the Piceance Basin show that reducing pad volume, maximizing proppant concentration, and reducing fracture complexity provided better production with cross-linked fluids.
A common trend in our industry is to minimize gel concentrations and utilize the lowest viscosity fluid available to place proppant Barrett Resources Corporation has found, for lenticular microdarcy formations, that one of the keys for success is enhanced proppant transport. This is achieved incorporating stable gels which maintain greater than 1000 cpa viscosity at bottomhole static temperature for the duration of the treatment. An extensive case study has been completed, involving over 500 fracture stimulation treatments in more than 175 wells, that illustrates the poor results achieved in the Williams Formation of the Mesaverde Group using low viscosity fluids. Low viscosity fluids invariably exhibit poor proppent transport. The statistical study shows that larger treatments utilizing "perfect proppant transport" fluids gain superior results. Based upon the case study, 100% economic success has been achieved upon incorporating stable fluids containing delayed breakers, reducing ped volumes to less than 5% of total job size, and minimizing echelon fractures while implementing a limited entry stimulation technique.
Author(s): Ely & Associates, J.W. Ely, Inc.; T.D. Brown, Barrett Resources Corporation; S.D. Reed, BJ Services
Paper Number: SPE 30479