Method of gravity assisted microbiologically enhanced oil recovery by improving the distribution of nutrients introduced into oil producing rock formations

A method for improving oil recovery comprising the steps of:

• selecting an oil-containing rock formation having geologic structures and well completions having a vertical permeability such that a water injection point is suitably located at a structurally high injection point of the oil-containing rock formation, wherein the structurally high injection point is above a water phase of the oil reservoir;
• injecting at the water injection point a nutrient-water mixture that stimulates resident microorganisms through gravity dispersion wherein the nutrient-water mixture percolates downward from the structurally high injection point through the water phase of the oil reservoir and the resident microorganisms contact oil trapped in a pore space during percolation;
• and
• releasing oil trapped in a pore space through interaction of the oil with the stimulated resident microorganisms such that the oil is freed to accumulate with upward gravity separation for production.