Initial fracs using small sand volumes in low viscosity fluid doubled production, but rapidly declined to pre-frac rate. Five wells were selected for refracturing with higher viscosity fluids, increased proppant concentration, larger proppant diameter and greater proppant mass. Average production increase due to the refracs was 620%.
This paper presents the results of an effort to improve productivity of the low permeability Escondido Formation in Webb County, Texas by the use of an improved hydraulic fracture design.
A fracture treatment using the polymer emulsion fluid system was designed to provide sufficient propped fracture length and area to maintain long term productivity of the wells. The polymer emulsion fluid was selected for its good proppant transport and low fluid loss properties. properties. Five previously drilled and stimulated wells and three new wells were fractured with the polymer emulsion treatments. Evaluation of pre and post frac flow rates and decline curves indicates an approximate doubling of recoverable reserves.
Author(s): D.P. Kundert, Halliburton Services; D.E. Smink, Consultant
Paper Number: SPE 7912