Recovery of heavy crude oil from shallow formations by in situ combustion

摘要

This invention comprises two steps for improving in situ combustion in shallow reservoirs: (1) use small well patterns preferably with injection to producing wells distance about 200 to 250 feet; and (2) after the front reaches a distance where the air flux is about 5 SCF/(ft. sup.2 -hr), or expressed another way, where the rate of frontal advance is about 0.4 ft/day, allow the air to "ride" on top of the pay zone while simultaneously water is injected at the oil-water contact below the air entry at the sand face of the injection well.