This paper shows proppant-induced pressure increase (i.e., tip screenout, p
ack, body pack, etc.) can relate to restricted vertical and lateral proppan
t distribution in hydraulic fractures. The discussion focuses on interpreta
tion of the character of the pressure response during the proppant stages.
Essentially, this pressure response relates directly to the quality of the
production response and the level of success. The technology presented has
been found to apply to all rock types, frac packs, and low-permeability and
water-frac applications.
This area of study is based on extensive engineering studies and common sen
se observation. Prior to publication of this work, this approach fit the re
servoir engineering interpretation of the producing character and advanced
fracture-treatment-pressure interpretation on a minimum of 1,000 wells. Whe
n premature proppant-induced friction occurs in the hydraulically induced f
racture, lateral and vertical proppant distribution adjacent to the pay int
erval can be affected negatively. Restricted proppant distribution results
in less effective stimulation because proppant is not distributed well both
vertically and laterally adjacent to the pay interval. The fracture stimul
ation may have been "put away;" but the negative aspects of how the stimula
tion was designed and implemented may have a significant effect on the resu
ltant production response.
To establish the basis for additional thought and investigation, there is d
iscussion about deficiencies in overly simplified pretreatment minifracture
-analysis procedures. Many of these analysis methods are not focused on the
proppant-induced friction character, and therefore do not optimize proppan
t distribution. Discussion is provided regarding differences in the proppan
t-induced friction character of various fracturing fluids which is not an i
nherent variable typically included in fracture-treatment-design methodolog
y.