With the boom of the oil and gas activities in south Texas, our understanding of completions and completion optimization of multistage horizontal wells has been greatly enhanced. Various multiple-stage isolation techniques are currently being utilized. The success of any horizontal shale well depends on contacting maximum reservoir rock, causing operators to reduce interval length which, in turn, increases drilling and completions cost.
To enable extending the interval length and increasing effectively stimulated rock volume, a new sequenced fracturing technique was developed and successfully tested. The technique relies on a novel fracturing fluid diversion blend delivered downhole at high concentration levels, which are achieved by using degradable fibers to stabilize fluid fronts and prevent slug dispersion when displaced. Thus, only a minor amount of material is used, and the pill is seamlessly integrated into a fracturing design and execution to divert stimulation fluids to under-stimulated regions of the wellbore. The material degrades completely after the fracturing treatment has been completed, leaving no residual formation or fracture conductivity damage.
The technique was first applied on several wells without extending stage spacing. The consistent results and diversion performance led to introducing the technique to wells with increased stage spacing, with the objective of achieving higher productivity and higher operations efficiency.
The early diagnostic data from wells completed with this technology demonstrate that diversion was achieved and reservoir contact improved. On wells with restricted internal diameter and long stage spacing, this technique was the only viable option to complete a section of the wellbore. Surveillance measurements indicate that the fracture treatment covered the interval as planned.