Mechanisms of Formation Damage and Permeability Impairment Associated With the Drilling, Completion and Production of Low API Gravity Oil Reservoirs

Abstract

Abstract The economic production of heavy oil reservoirs requires an indepth understanding of the specific mechanisms of formation damage which are unique to these types of formations. This paper will provide a brief description of some of the dominant mechanisms of permeability impairment which can occur in low API gravity oil-producing zones. These include: Drilling induced damage solids entrainmentfines migrationrock/fluid incompatibilitiesfluid/fluid incompatibilities Reactive clay induced damage Formation of emulsions (water-oil, oil-water) Foamy oil phenomena Sand control and consolidation issues Completion induced damage, acidizing, solvent injection, etc. Thermally induced formation damage mineral transformationsmineral and formation dissolutionwettability alterations Biologically induced formation damage issues Formation damage issues peculiar to the drilling and completion of horizontal wells in heavy oil producing zones. This paper provides a general overview of many of the potential types of formation damage which drilling, production and reservoir engineers as well as geologists and geophysicists should be aware of when planning exploitation programs for heavy oil plays.