Senior Geologist

Job Purpose Senior Geologist, Lead and conduct integrated G&G studies to evaluate petroleum systems, hydrocarbon resources, and exploration opportunities. Responsible for subsurface interpretation, hydrocarbon-in-place assessment, prospect maturation, and exploration well targeting through the integration of geological, geophysical, petrophysical, reservoir, and drilling data. Provide technical leadership, mentor geoscientists, and support high-quality, value-driven exploration decisions.

Key Accountabilities Lead petroleum system synthesis and integrated subsurface evaluation to assess hydrocarbon potential, identify exploration opportunities, and recommend effective exploration strategies. Lead reservoir evaluation and characterization by integrating petrophysical, pressure, fluid, core, well-test, and production data to define net pay, reservoir quality, hydrocarbon contacts, fluid distribution, and field development implications.

Lead the integration of geological, geophysical, petrophysical, and production data to develop and validate net sand, net pay, gross rock volume (GRV), and reservoir distribution maps for deterministic and probabilistic resource evaluations. Conduct, review and challenge volumetric estimates of hydrocarbons initially in place (STOIIP/GIIP) and recoverable resources. Coach team members on uncertainty assessment, risk-based evaluation methodologies, and volumetric best practices align with PTTEP standard and guidelines.

Serve as a key subsurface focal point with Exploration, Development, Drilling, and Reservoir Engineering teams to optimize prospect maturation, target definition, well placement, and data acquisition programs, maximizing hydrocarbon recovery and value creation. Provide strategic guidance during well planning activities to ensure proposed trajectories effectively address subsurface uncertainties and achieve geological objectives while maintaining cost efficiency and operational feasibility.

Monitor drilling, logging, coring, testing, and formation evaluation activities. Provide senior geological support and timely operational recommendations to mitigate subsurface risks and optimize data acquisition opportunities. Conduct peer reviews and facilitate technical discussions to improve the quality and robustness of geological interpretations, subsurface models, and team decisions.

Promote constructive challenge, knowledge sharing, and the application of lessons learned across projects. Develop the technical capabilities of junior and intermediate geoscientists through structured coaching, on-the-job training, technical reviews, and knowledge-transfer initiatives, supporting succession planning and continuous capability development. Drive continuous improvement in geological workflows, interpretation methodologies, and subsurface evaluation processes by incorporating industry best practices, emerging technologies, and organizational learnings.

Professional Knowledge & Experiences Bachelor’s degree or higher in Geosciences Min. 15+ years of experience in E&P Business related Highly require experience in petroleum exploration in various exploration projects/prospects Experienced in Coaching and mentoring capability Good background on subsurface software (Petrel and DSG etc.) and systems Good communication and interpersonal skills Good project management skill is required Good command of both written and spoken English