Many fields in Argentina have multilayer reservoirs that require various stimulation techniques, mainly hydraulic fracturing. A variety of formations and types of reservoirs, such as conventional (mature fields) and unconventional (tight gas and shale), are present in the Golfo San Jorge and Neuquen 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 the last decade, new technologies were introduced and developed to help achieve greater efficiency and reduce time and costs associated with completions for these fields. This paper presents experiences gained using two types of technologies.
First, a new conventional straddle-packer system (SPS) was used in conjunction with a workover unit, which was part of a technological collaboration agreement between an operator and service company. It was mainly applied in conventional reservoirs, mature fields, in wells with up to seven fracture stages, and in new or recompletion wells. Second, a pinpoint technique was used, called hydrajet perforating annular-path treatment placement and proppant plugs for diversion (HPAP-PPD). This technique was applied in new wells (rigless completion) and all types of reservoirs, both conventional and unconventional (tight gas and shale), and allowed performing up to 30 separate fracture stages in a single well, with three stages completed in a 12-hr operation.
These completion methods allowed operators to focus treatments in desired zones with specific treatment designs based on reservoir characteristics. Several case histories are presented for different basins, formations, and reservoirs types, as well as lessons learned and completion time reductions.