Heavy Oil Reservoir Mechanisms, Linbergh and Frog Lake Fields, Alberta Part II: Geomechanical Evaluation

Abstract

Field results from many heavy oil reservoirs in the Lindbergh and Frog Lake fields in northeastern Alberta suggest that primary recovery is mainly governed by the processes of sand production and foamy oil behaviour. Sand production leads to the creation of high porosity zones with increased permeability, while foamy oil generation provides the necessary support mechanism to sustain higher production rates. PanCanadian Petroleum Limited and Centre for Frontier Engineering Research (C-FER) conducted experimental and numerical studies to understand the various reservoir mechanisms contributing to the high primary production recovery observed in the Lindbergh and Frog Lake fields. Laboratory tests were conducted to study the foamy oil behaviour and evaluate its contribution to the enhanced primary production observed in the field. The numerical modelling included a series of idealized models developed and analyzed to determine the most probable shape of the sand-producing zones. The evaluation focussed on matching not only the observed oil production but also the observed sand volumes removed from the reservoir. The analysis from vertical well simulation was also extended to horizontal wells. The evaluation of heavy oil reservoir mechanisms for Lindbergh and Frog Lake fields is reported in two parts. Part I includes field testing and preliminary reservoir simulation based on the production data. Part II includes analytical and numerical studies for coupling the effects of sand and oil production, and laboratory testing of unconsolidated sand under foamy oil conditions. Introduction The observed primary oil production of many heavy oil reservoirs in the Lindbergh and Frog Lake fields in northeastern Alberta has been significantly higher than predicted by classical darcy flow models. PanCanadian Petroleum Limited (PanCanadian) and Centre for Frontier Engineering Research (C-FER) conducted experimental and numerical studies to understand the various reservoir mechanisms contributing to the observed high primary production recovery. This evaluation was conducted in two parts. Part I of the evaluation of heavy oil reservoir mechanisms for the Lindbergh and Frog Lake Fields was previously reported by the authors in Ref. (1). Part I included geological description of the Lindbergh and Frog Lake reservoirs, a summary of various field tests conducted in the area to evaluate recovery mechanisms and the results of reservoir simulation. P. 87

Production froide des huiles visqueuses. Première partie : Observations sur champ

“…Dusseault Dispositif expérimental pour étudier la compressibilité des sables à huile lourde contenant du gaz (d'après . Solanki and Metwally, 1995). Évolution de la pression de pore pendant le déchargement des contraintes externes pour différents GOR (d'après .…”

“…Évolution de la pression de pore pendant le déchargement des contraintes externes pour différents GOR (d'après . Solanki and Metwally, 1995).…”

Simulating Cold Heavy Oil Production With Sand by Reservoir-Wormhole Model

“…An operational strategy of producing heavy oil with sand has been widely used for a decade in Alberta and Saskatchewan (1)(2)(3)(4)(5)(6) . However, a poor understanding of this production process, a recovery rate limited to ~12 -20% in appropriately screened reservoirs, and difficulties in well management (i.e., repeated workovers) have been the weak points for this technology (7) .…”

Simulating Cold Production by a Coupled Reservoir-Geomechanics Model With Sand Erosion

“…Sand production, on the other hand, has been proven a most effective way to increase well productivity both in heavy oil and light oil reservoirs 1,7 . A typical 4-10 fold increase in oil production is normal in heavy oil reservoirs (Cold Production) [1][2][3] , and up to a 44% increase in sand-free rate after a certain amount of sand production in conventional oil reservoirs has been reported 8,9 . For conventional oil producers, both enhanced production and improved sand-free rate are highly desirable.…”