Improvements in Multistage Fracturing, Remolino Field, Mexico

Abstract

During the past few years, the oil industry in Mexico has taken significant steps toward improving the economic performance of hydrocarbon-producing wells in the very low-permeability, heterogeneous, compartmentalized, and hard-to-produce reservoirs of the Chicontepec paleochannel through the application of high-impact technologies used in unconventional wells for drilling, logging, perforating, zonal isolation, completions, fracturing, etc. that unquestionably helped improve well performance. However, the proper integration of these new technologies in the heavy-oil Remolino field, located in southern Chicontepec, has shown the potential to deliver better results in terms of production and recovery improvement. Some of the production problems of Remolino field include previous ineffective stimulations, low reservoir contact area, poor well productivity, and extremely low recovery factors. These problems were addressed by modifying (i) the well architecture from vertical to horizontal, (ii) the zonal isolation from conventional cemented to engineered cemented and swell-packer openhole, (iii) the wellbore-reservoir connection from perforating to hydrajetting and ball-activated sleeves, (iv) the fracturing fluids from conventional crosslinked to hybrid fluids, and (v) the fracture design and pumping schedule to achieve the required length and conductivity. The application of these completion technologies in Remolino field have evolved, based on production results and operational efficiency, from the simplest perf-and-plug method in vertical wells to more complex coiled-tubing assisted fracturing and faster ball-activated sleeves in horizontal wells. Lowering the completion time also has been a primary driving factor for choosing the proper completion option for each individual well, attempting to achieve faster fracturing and quicker production. The experience of applying new technologies in Remolino field is presented in this paper, including comparisons between openhole and cemented laterals, fracture stages with single and multiple cluster/ports, number of fractures/fracture spacing, and lateral length required to improve the production without compromising completion costs. To date, the benefit of the overall application has been a five-fold production increase and, as expected, a significant improvement in the recovery factor.

The Effect of Thermal Shocking with Nitrogen Gas on the Porosities, Permeabilities, and Rock Mechanical Properties of Unconventional Reservoirs

“…Hydraulic fracturing is a major technique to produce economically from unconventional oil and gas reservoirs. Numerous researches have been conducted in order to optimize hydraulic fracturing operation to maximize oil and gas production from unconventional reservoirs [1][2][3][4][5]. Connecting hydraulic fractures with existing natural fracture network in formation matrix enhances the efficiency of stimulation process and increases resultant hydrocarbon production rate.…”