A Proxy Based Approach for the Preliminary Evaluation of New Gas Condensate Field for Development

With increase in gas demand to meet both export and domestic gas obligations, amidst oil price volatility, it is imperative that oil and gas companies embarks on activities that will minimize investment risk and initiate robust development plans. It becomes a very big challenge at the onset of new gas condensate field development owing to limited geological and engineering data. To ascertain the technical feasibility and economic attractiveness of a gas condensate field, a very lengthy study work is required to unravel the complex interplay of subsurface uncertainties; hence, a quick screening tool is therefore required for quick decision making and investment prioritization. A proxy of recoverable reserve for the new field was developed for this purpose using design of experiment (DOE) and response surface model (RSM). However, although DOE was initiated in the industry to reduce computation, it remains computationally expensive especially in compositional simulation were many degrees of freedom exist in the uncertainty parameters. This study presents a new gas condensate field case study where both engineering and earth model variables were systematically varied to assess the impact of main uncertainties on forecast level of gas condensate production/reserves using RSM proxy. This approach was validated when key risks associated with new gas condensate field development were quantified. This paper provides a technical and economic feasibility assessment tool for low risk decision. It will also assist in data acquisition program and roadmap construction especially when the most influential uncertainty parameters influencing gas and condensate recoveries are identified.