Abstract: This invention is a method of developing a sedimentary basin containing hydrocarbons, by using basin simulation. Starting with gridded representations representative of a basin for each time step of a simulation, for each time step and in each cell of the gridded representation the following steps are performed. First a determination of at least one amount of biogenic gas produced in the cell for the time step is preformed followed by determining at least one amount of biogenic gas dissolved in water present in the cell at the time step, and determining therefrom an amount of free biogenic gas in the cell at the time step; then, accounting for advective transport of the quantity of biogenic gas dissolved in the water of the cell at the time step.

Abstract: This invention is a method of developing a sedimentary basin containing hydrocarbons, by using basin simulation. Starting with gridded representations representative of a basin for each time step of a simulation, for each time step and in each cell of the gridded representation the following steps are performed. First a determination of at least one amount of biogenic gas produced in the cell for the time step is preformed followed by determining at least one amount of biogenic gas dissolved in water present in the cell at the time step, and determining therefrom an amount of free biogenic gas in the cell at the time step; then, accounting for advective transport of the quantity of biogenic gas dissolved in the water of the cell at the time step. Application: petroleum reservoir exploration and development for example.