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This paper documents pinpoint fracturing (PPF) in Argentina. The implementation of this method has resulted in 193 fractures in 22 wells since October 2006. The PPF method creates perforations by pumping abrasive slurry down the coiled tubing (CT) through a jetting nozzle, while the main treatment is then pumped down the annulus around the CT. Isolation between fracture treatments is accomplished using sand plugs (preferred method) or composite bridge plugs. This technique has allowed greater selectivity in the stimulation of the areas to be treated; it has also allowed a more aggressive fracture treatment in terms of percent pad and the final proppant concentration because the CT is at the location in case of screen out. In gas fields, it offers the advantage of completing the well without killing it. Different reservoirs with varying depths, temperature, types of fluid, and petrophysical conditions in the basins Golfo San Jorge and Neuquina were stimulated with different fracture fluids, proppant types, and frac gradients. The Neuquina basin required fracturing without using a workover rig in oil and gas fields near the community, while significantly diminishing the working times with a reduction in environmental impact and noise generated during the completion. However, the main goal was the reduction of completion times in each well performed in the different basins of Argentina. Introduction New hydraulic-fracturing technologies introduced in Argentina not only provide application of new products or processes; but, their versatility allows them to be used in different types of reservoirs and conventional completion practices. On evaluation of different technologies, it is assumed that the selected technology and its application should lead to diminished completion times and cost, as well as improve selectivity and production. Based on these criteria, it was determined that hydrajet-perforating annular-path treatment-placement and the proppant plugs for diversion (HPAP-PPD) method using CT could fulfill the expected needs. This study shows the application of this in various fields, focusing on each of them to solve problems, such as application in mature fields, gas reservoirs, and low-permeability sands. The value of HPAP-PPD is well documented in vertical-well completions in many areas in the U.S. (East et al. 2005; Fussel et al. 2006; Helj et al. 2006; Peak et al. 2007), Australia (Gilbert et al. 2005; Beatty et al. 2007) and Russia (Pongratz et al. 2008). The maximum number of individual fracture treatments performed on a single well outside of North America is currently 30, performed on a well in Argentina, although no usage limitation for the method is known. Description of HPAP with Proppant Plug Diversion (HPAP-PPD) Using CT, hydrajet perforating, annular-path treatment placement, and proppant plugs for diversion, the (HPAP-PPD) method was introduced to the industry in 2004 (Surjaatmadja et al. 2005). Initial work with the method was related to vertical-well completions. The method overcame the need for monobore completions because there were no mechanical devices to set inside the casing.

One of the most promising targets for resource rock stimulation in South America is the Vaca Muerta (VM) shale in western Argentina. Because of high initial costs and also the typical reservoir information that must be acquired, it is common practice for operators to begin exploration projects with vertical wells. This is also the case for unconventional reservoirs, so initial vertical wells are used for reservoir characterization/initial comprehension and also to test the productivity of the different intervals.Within the Neuquina basin, existing vertical wells were typically drilled to produce reservoirs below the VM source rock. Presently, with these reservoirs depleted in many areas, existing wells are often a great opportunity to investigate this upper unconventional target. Unfortunately, most of these wells are not viable candidates because they were designed to be completed through tubing. Casings and wellheads, in general, are not sufficiently strong to support pressure requirements for fracture stimulation of unconventional reservoirs. This paper discusses the preparation of a well originally drilled in 1974 to allow for the new objective of hydraulic fracturing the VM shale to test the productivity of its different intervals. A coiled tubing (CT) assisted pinpoint completion technique (hydrajet perforating and annulus fracturing) was used to independently stimulate small intervals. To help assure that most of the reservoir was indeed stimulated, 12 single-zone fracturing stages were used for 130 meters of gross interval.To isolate the upper (weakest) section of the wellbore, a 4 1/2-in. P-110 casing and swellable packer were installed.

fax 01-972-952-9435. AbstractHydraulic fractures are used worldwide to enhance oil and gas production. In many cases, the stimulation jobs cover multiple intervals and the evaluation of the individual zones is not a straightforward process.In Colombia (Figure 1), it was proposed to HOCOL to run the crossed dipole sonic, inside casing before and after a hydraulic fracturing job, to evaluate changes in anisotropy due to the treatment. This paper presents the complete process, including the planning and evaluation of the logging and hydraulic fracturing, and the use of this technique to evaluate hydraulic fracturing effectiveness when multiple zones are open and fractured simultaneously.The planning process includes the use of the dipole sonic to determine rock properties and the calibration process to adjust the computation of sanding potential and fracturing pressures.The use of acoustic anisotropy in cased hole proved to be an effective method for evaluating the effectiveness of the fracture treatment and for defining the characteristics of the resulting fractures. This is an innovative technique; a second application well is presented in this paper including the results.

Many fields in Argentina have multilayer reservoirs that require various stimulation techniques, primarily hydraulic fracturing. A variety of formations and types of reservoirs, such as conventional (mature fields) and unconventional (tight gas and shale), are the main focus in the Golfo San Jorge and Neuquén basin. The hydraulic fractures created in these basins present a variety of conditions and challenges related to depth, well architecture design, bottomhole temperature (BHT), reservoir pressure, and formation permeability. In 2006, a pinpoint completion technique was introduced to help achieve greater efficiency and reduce time and costs associated with completions. This paper presents experiences gained using this technology and proving such versatility in different types of reservoirs. The pinpoint technique, called hydrajet perforating annular-path treatment placement and proppant plugs for diversion (HPAP-PPD), was applied in new wells at different reservoir conditions. The history and evolution of this technique in Argentina was initiated in conventional oil reservoirs (mature fields in Golfo San Jorge) and then was introduced in the Neuquén basin in gas well completions. Throughout the last seven years, this technique has been tested and implemented in tight gas wells. More recently, it was used to improve a completion technique in a shale oil well. This completion method allowed operators to focus treatments in desired zones using specific treatment designs based on reservoir characteristics. Several case histories are presented for different basins, formations, and reservoirs types, highlighting lessons learned and reduced completion time.