Archie’s Equation

Archie's Equation is a formula used in the oil and gas industry to estimate how easily electricity can pass through a rock formation to determine if it contains oil or water. It relates the rock's electrical resistivity to its saturation with fluids—either water or hydrocarbons. Essentially, it helps geologists interpret well logs by predicting how much of the pore space is filled with water, aiding in assessing a reservoir's productivity. The equation considers the resistivity of the rock when it’s fully saturated with water and adjusts for partial water saturation, providing valuable insights into the subsurface reservoir conditions.