A comprehensive analysis of innovations to overcome challenges in horizontal well hydraulic fracturing in tight reservoirs: a case study on the lower Devonian in Berkine Basin, Algeria
摘要
Horizontal wells combined with multi-stage hydraulic fracturing represent the most effective approach for extracting resources from tight reservoirs. Hydraulic fracturing involves injecting formulated fluids at high pressure to fracture the formation, thereby enhancing permeability and facilitating hydrocarbon flow. Proppant is introduced to maintain the flow pathways open. In horizontal wells, performing multiple fracturing stages is critical to achieve economically viable production. However, unforeseen challenges can arise, leading to suboptimal outcomes. This case study explores a hydraulic fracturing project of a tight reservoir in Algeria, located at a depth exceeding 4,200 m, with formation pressure around 7,000 psi and temperature reaching 150 °C. In 2018, significant challenges were encountered during fracture initiation in three horizontal wells. Extremely high breakdown pressures, combined with severe wellbore damage, resulted in only one stage being successfully completed following heavy intervention efforts. This study details the encountered challenges, their root causes, and the taken remediation actions, highlighting the importance of 1D geomechanical model to optimize fracture placement. It illustrates how real-time analysis of multiple injection tests guided decisions on using innovative perforation techniques and specific acid stimulation treatments. This study underscores the uniqueness of each tight reservoir, requiring specific design from well orientation selection to hydraulic fracturing execution. The combination of stress complexities, high pressure and temperature conditions, drilling orientation and wellbore damage was analysed to improve the reservoir characterization. These insights help mitigate risks and enhance the success rates of hydraulic fracturing in this reservoirs, emphasizing the need for tailored approaches in such projects.