Position summary Ad Terra is seeking a highly experienced Senior Reservoir Engineer with strong expertise in reservoir simulation and field development planning. The successful candidate will bring deep technical expertise combined with a pragmatic, client-focused approach, with exposure to project management and coordination activities. Experience in reservoir simulation software support or troubleshooting is considered a strong advantage, and experience with advanced modelling techniques such as EOR processes, compositional modelling or ensemble modelling would be highly valued. The role is primarily focused on delivering technical excellence in reservoir engineering, while contributing to integrated subsurface studies and, where relevant, supporting project delivery. Key Responsibilities Lead and perform reservoir simulation studies for field development, optimization, and forecasting Build, calibrate, and run dynamic reservoir models in large reservoirs with complex geological settings. Applying advanced modelling techniques such as EOR processes, compositional modelling or ensemble modelling when relevant Perform reservoir performance analysis using simulation, material balance, and analytical techniques Support reservoir management and surveillance activities Contribute to: Field development planning Production optimization Subsurface uncertainty and risk assessment Collaborate with multidisciplinary teams (geoscience, production, facilities) to deliver integrated solutions Provide technical support and troubleshooting related to reservoir simulation workflows (internal teams or clients) Interface with clients to present results and provide practical, high-quality recommendations Additional Responsibilities Support or coordinate project activities, timelines, and deliverables Contribute to project reporting and client communication Required Qualifications Master’s degree (or higher) in Petroleum Engineering or related field 10–15 years of experience in reservoir engineering Strong expertise in: Reservoir simulation (core requirement) Reservoir performance analysis & forecasting Field development planning