Over 145 pin-point fracturing (PPF) treatments have been performed in Australia's Cooper Basin since the introduction of the technology in mid 2004. The PPF method creates perforations by pumping abrasive slurry down the coil tubing through a jetting nozzle while the main treatment is then pumped down the annulus around the coil tubing. Isolation between fracture treatments is accomplished using sand plugs (preferred method) or composite bridge plugs. Fracturing treatments in the Cooper Basin have historically been problematic due to the combination of high rock strengths (average modulus of sand/shales of 4-5 million psi), proximity to coal formations, high formation temperatures (250-400 deg F), and high fracture gradients (often above 1.0 psi/ft). Screen-outs occur in ~40% of all treatments, so useful experience has been obtained on managing these events. This paper discusses the successful and unsuccessful experiences that have occurred using PPF techniques in these harsh situations. While PPF has improved well performance, the placement of treatments is still problematic. The paper details the experiences with varying abrasive jetting and breakdown techniques, modifying the bottom-hole assembly (BHA), changing the isolation techniques, modifying the treatment schedules, and extending PPF treatments to older wells.

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