The necessity to exploit hydrocarbon resources further down the resource triangle has resulted in the industry attempting to evaluate large and more-challenging resource plays due to the scarcity of conventional reserves. The Jimusaer field, located in the Junggar basin in western China, represents such a scenario and covers a surface area exceeding 300,000 acres with a targeted reservoir thickness of 650 ft located between 9,100 and 14,500 ft true vertical depth (TVD).
Typical exploration programs include extensive data collection of reservoir and hydrocarbon properties with respect to structural location. The assessment and evaluation of such data improve the understanding of the subsurface uncertainties and associated risk. In Junggar basin, given the uncertainty in well productivity, increased attention to the hydraulic fracturing process was required. The process, which included the application and combination of several types of technology, was built upon and optimized through the initial 28 vertical wells.
To further improve well performance, long horizontal laterals combined with multistage hydraulic fracturing were needed to provide proof of commercial productivity and subsequent field development, which, for several years, was not thought to be possible. Based on the initial vertical well results, three horizontal wells were designed based upon the improved reservoir understanding. This phase was meant to further advance the understanding of the subsurface and completion and stimulation technologies while identifying areas for future productivity improvement.
Finally, the unique geological properties of this reservoir required different strategies and technology deployment to make them viable and sustainable in terms of reservoir and completion quality factors. The successful application of a locally developed technology plan and pilot program through a multidisciplinary approach further demonstrated the suitability of a given technology with the lessons learned being captured and incorporated into future well designs.