Application of Technologies for Improved Drilling, Hydraulic Fracturing, and Production Increase – Case Studies from Deep and High Pressure Gas Wells

Integration of technologies and application of innovative practices in drilling, completion, acid stimulation, and hydraulic fracturing have significantly contributed to the successful development of tight gas reservoirs. The well planning and development procedures entail careful selection of several critical parameters such as drilling azimuth, lateral length, well trajectory, drill-in fluids, well completion methods, stimulation fluid properties, fracture placement technique, proppant types, treatment volumes, and pump schedule. All of these critical parameters impact fracture dimension, proppant transport and placement, as well as stimulation efficiency and effective post-frac clean-up. Depending on the reservoir rock properties and stress profile in the near wellbore (NWB) and the far field, the effectiveness of hydraulic stimulation (fracturing or matrix acidizing) in connecting the wellbore to the undamaged virgin reservoir, as well as maximizing reservoir contact (RC) area and enhancing flowback of treatment fluids to restore proppant conductivity, dictate the well potential, sustainable gas rate level, and ultimate recovery. Successful fracture stimulation is therefore, measured not only by proper pumping and placement of the designed treatment, but more importantly by the post-treatment stabilized production rate after the well is cleaned up and flowed back. Due to the diverse nature and characteristics of Saudi Arabian reservoirs producing rich gas from deep, high pressure and temperature formations, drilling and fracture treatment parameters, procedures, and methodologies are continuously being improved to obtain even better results. Based on reservoir properties and production expectations, this paper summarizes the collaborative approaches undertaken to carefully select candidates, drilling plans, completions, and fracture treatment designs, thereby providing a real example of how reservoir management, petroleum engineering, drilling and technology work in harmony to achieve the ultimate goal—high rate wells, sustained production, high rate of return, and expeditious payback. This rigorous process includes important factors, such as real-time geomechanical modeling to predict the correct mud weight window and borehole stability issues while drilling long laterals toward the minimum horizontal in situ stress ( min) direction.7 Selection of a completion system to effectively fracture stimulate the well and place acid or proppant in multiple stages, and use of stimulation fluids that are compatible with the reservoir rock, cause minimum damage to the proppant, and enhance clean up without compromising the ultimately desired fracture dimensions are among the most important elements of this process. Engineered pump schedules have proven advantageous in minimizing premature screen outs that can often happen in high-stress tight reservoirs. This paper shows how proper well planning is important for successful fracture treatment and increased production.