Limited entry extended to massive hydraulic fracturing

Limited entry techniques have recently been applied in massive hydraulic fracturing (MHF) of the Niobrara/Codell intervals of the Denver-Julesberg basin. Erratic surface treating pressure behavior and partial-to-complete well screenouts were frequently encountered during simultaneous treatment of these zones. This may be indicative of a lack of control of interzonal treatment fluid placement. There are field-proved solutions to this problem of interzonal fluid entry control during limited entry MHF. This first of two article examines the downhole interactions that occur.