Packerless Multistage Fracture-Stimulation Method Using CT Perforating and Annular Path Pumping

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractRecord high prices for oil and gas have increased the opportunity for producers to maximize the value of their assets. Under current market conditions, reservoirs previously considered marginal or even noneconomic can yield an acceptable return on investment and are increasingly considered for well completion. Many are lower-permeability formations that require fracture stimulation during the completion phase to deliver economic rates. In the latter part of 2004, a new stimulation technique was introduced to the industry, providing well operators a method to achieve multiple-zone fracture stimulation while controlling stimulation costs. By mid-2005, this new process had been evaluated by several operators in the US as well as Canada and Australia with very positive results.This new process offers the opportunity to perforate and stimulate multiple pay zones with a single well intervention, often within a single day. The technique employs a hydraulic jetting assembly on coiled tubing (CT) to erode perforations, immediately followed by pumping a fracture-stimulation treatment through the annulus between CT and casing. At the completion of the first fracturing stage, small-volume, highproppant-concentration slurry is left in the wellbore to provide isolation of the just-stimulated zone from subsequent targets. In some applications, a wellbore screenout may also be induced to improve the temporary isolation of this zone. This sequence (perforate, stimulate, isolate) is repeated until all desired zones have been treated. Following the final stimulation stage, the well is cleaned out with CT and turned over to production. If needed, N 2 gas can be pumped through the CT to kick-off the return flow.This paper describes the operational aspects, advantages, and limitations of using this new multistage perforating and fracturing technique with example field applications.

Pinpoint Fracturing Technologies: A Review of Successful Evolution of Multistage Fracturing in the Last Decade

“…The maximum number of individual fracture treatments performed on a single well so far is 39. The value of this technique has been well-documented in vertical well completions (McDaniel 2002;Beatty et al 2007;McDaniel et al 2006;East et al 2005). The initial and probably the best documented extensive use of the HPAP with PPD method occurred in the fairly shallow Diatomite play in California (Hejl et al 2006).…”

“…Using proppant plugs as a diversion method for fracturing multiple intervals was popularized with the Pine Island Fracturing Technique in the early 1960s (Harrison 1972;McDaniel 2005). After perforating and fracturing an interval, a measured load of gravel was dumped across the perforated interval and allowed to settle.…”