Probabilistic Techno-Economic Appraisal of Prospective Hydrocarbon Resources in Five Turbidites, Offshore Uruguay

Abstract

This paper presents a probabilistic techno-economic evaluation of several turbidite prospects recognized, through 3D seismic, in deep to ultra-deep water of the Punta del Este and Pelotas sedimentary basins, offshore of Uruguay. The production potential of many prospective turbidite reservoirs on the Atlantic margin has been recognized before, and new turbidite prospects were identified in Uruguay's maritime zone after analyzing data from the world's deepest water-depth well (Raya-X1) drilled in 2016. The estimated ultimate recovery of oil and gas was determined, for each prospect, by carrying out probabilistic resource analyses (Monte Carlo simulations) using 3D seismic and key parameters from analog turbidite fields located in sedimentary basins along the Atlantic margin. Black oil fluid was assumed and the production concept involves FPSO vessels. The produced oil would be exported via tankers and the associated gas would be either sent to shore through a gas pipeline, or re-injected into the formation. For the economic evaluation, the latest fiscal terms of the applicable production-sharing contract, for offshore assets in Uruguay, were considered. The outcomes of the probabilistic economic analyses include, for each prospect, several key performance indicators such as: net present value, internal rate of return, maximum negative cash flow, breakeven oil price, government take and entitlement percentage of hydrocarbons. These indicators were determined after running Monte Carlo simulations, which considered probability distribution functions for fixed and variable capital and operational expenditures, along with well productivities and decline rates. Regarding the economics of the project, several scenarios of incremental profit oil for the government and maximum association percentage for ANCAP, the National Oil Company of Uruguay, were evaluated. The cases considered show how key negotiables and variables, featuring in the tender process offered to oil companies interested in Uruguay's offshore hydrocarbon assets, may affect the economics and development solutions of a typical field development project. Considering a plausible base case of 20% ANCAP association and no incremental profit oil for the state, the results show that, for the biggest prospects, the breakeven oil price is situated near 60 USD/bbl. The analysis also shows that the smaller prospects would need to be developed as satellites of the nearby principal prospects in order to become attractive for development. This study sheds light on the exploration potential of turbidites, offshore of Uruguay, and analyzed resource volumes, production profiles and economic returns of a hypothetic development in the case of a commercial discovery. The analyses provide useful templates for international oil companies, which, under the new and more flexible Uruguay Open Round licensing regime, may be interested in the exploration and imminent development of the Uruguayan offshore sedimentary basins.