👉 Drilling math, often used in drilling operations, is a systematic approach to estimating the volume of hydrocarbons (oil or gas) in a reservoir based on measured data. The process involves calculating the volume of the reservoir rock and then multiplying it by the recovery factor, which is the percentage of hydrocarbons that can be economically extracted. The formula typically used is: Volume = Area × Depth × Thickness × porosity × saturation × recovery factor. For instance, if a well has a circular cross-section with an area of 1000 m², drilled to a depth of 3000 m, with a wall thickness of 10 m, and a porosity of 20%, and a recovery factor of 60%, the volume would be 300,000 m³ (1000 × 3000 × 10 × 0.20 × 0.60). This method provides a reliable estimate of the total hydrocarbon reserves, crucial for planning production and investment decisions.
