Strategic Implementation of Horizontal Re-Entry Drilling in Sarir and Messla Fields: A Case Study by AGOCO

Mohammed .B . Faraj, Sirte Oil Company for Production, Manufacturing of Oil and Gas, Marsa El Brega, LibyaFollow
Adel M . Salem, Department of Petroleum Engineering, Faculty of Engineering and Technology, Future University in Egypt (FUE), Cairo, Egypt
Ahmed .Z. Noah, Exploration Department, Egyptian Petroleum Research Institute, Naser City, Cairo, Egypt

Article Type

Research Paper

Corresponding Author

Mohammed .B . Faraj

Abstract

Sarir and Messla are two of the largest oil fields operated by the Arabian Gulf Oil Company (AGOCO). Over time, intensive production activities in these fields have led to significant reservoir depletion. To sustain oil output, horizontal drilling emerged as an optimal solution. However, the high costs associated with horizontal well drilling, compounded by budgetary constraints, limited AGOCO's ability to fully meet its production targets using conventional horizontal drilling techniques. As major new discoveries become increasingly rare and technically complex, reservoir engineers are tasked with maximizing recovery from existing assets through improved and enhanced oil recovery (IOR/EOR) techniques. Developing economically viable field development plans remains a key challenge, particularly given the technical and financial limitations involved. Nevertheless, rapid advancements in technology—especially in directional drilling and geosteering—have enabled operators to overcome many historical obstacles. In response to these challenges, the AGOCO Reservoir Engineering Department has adopted a cost-effective and innovative operational strategy: sidetracking and horizontal re-entry drilling. This approach aims to access undrained reserves and enhance reservoir performance by increasing subsurface withdrawal in a financially sustainable manner. The first deliberately drilled horizontal re-entry well was executed in the Sarir L-field, where an existing horizontal well (H1) was successfully converted into a re-entry well. This intervention resulted in a tenfold increase in oil production, alongside a significant reduction in water cut to zero. A second re-entry well, H2, was implemented in the Messla field, transforming a former observation well into a productive asset. This paper presents the innovations, driving motivations, operational actions, technical challenges, and outcomes associated with the first horizontal re-entry drilling projects in the Sarir and Messla fields. It also highlights key lessons learned, offering valuable insights for future applications in mature oil field development.

Keywords

Re-entry, Sidetracking, Horizontal Drilling, IoR, Economics.

Recommended Citation

Faraj, Mohammed .B .; Salem, Adel M .; and Noah, Ahmed .Z. (2026) "Strategic Implementation of Horizontal Re-Entry Drilling in Sarir and Messla Fields: A Case Study by AGOCO," Egyptian Journal of Petroleum: Vol. 35 : Iss. 1 , Article 8.
Available at: https://doi.org/10.62593/2090-2468.1092