Upgrading Multistage Fracturing Strategies Drives Double Success after Success in the Unusual Saudi Gas Reserves

Abstract

AbstractOpen hole multistage fracturing (MSF) technologies have been deployed in Saudi Arabia’s tight gas fields with the objective of maximizing reservoir contact through inducing independent multiple fractures and increasing matrix contribution in both carbonate and sandstone formations.Full achievement of this objective has not been straightforward or quick. While good well productivity was seen from the early wells completed with MSF technologies, several technical issues had to be investigated and resolved when the technology was initially introduced. These issues included mechanical and differential sticking during the technology deployment phase as well as not attaining clear fracture signatures for the subsequent fracture stages after fracturing the first stage during the well treatment operations due to potential hydraulic communication between the fracture stages in carbonate formations.Accordingly, improvement strategies were implemented to mitigate these limitations and realize the full advantage of using MSF technologies in developing tight gas reserves. This paper discusses these strategies and show how they have been successfully utilized to further improve the application of multistage fracturing.Furthermore, the paper addresses a scheme for increasing the success rate for the secondary (contingency) coiled tubing (CT) ball seat milling operations for MSF systems.Also, the paper analyzes the production results for wells completed with MSF technologies and compares them with that of wells completed using other techniques. Additionally, the paper takes a holistic approach integrating the various technical displinces involved in ensuring optimum results are obtained.