Oil Field Model Helps Assess Recovery Potential Of Venezuela’s Extra-Heavy OilImage. Location of the oil fields in the Maracaibo Basin and the Eastern Venezuela Basin where chemical enhanced-oil-recovery techniques were evaluated. Venezuela holds vast reserves of extra-heavy oil, but extracting it is extremely difficult. While a typical recovery factor runs around 60% for light oil and up to 20% for heavy oil, the extra-heavy oil field analyzed by the Skoltech-led team has a recovery factor of just 4%. “Water is injected to raise pressure in the formation, but it does not address the viscosity of extra-heavy oil.