Method for building a reservoir model populated with petrophysical parameters

A computer-implemented method for building a three-dimensional model of a reservoir, comprising:

• defining a pre-sedimentation model comprising a bottom surface comprising a plurality of cells, and
• iterating a plurality of deposition modelling steps, including:
• simulating deposition of a layer of sediments on the bottom surface or a previously-deposited layer of sediment, each layer corresponding to a determined period of time of sedimentation and comprising a plurality of cells, and
• computing petrophysical parameters associated to at least a cell of the generated layer,
• wherein simulating deposition of a layer of sediments comprises:
• introducing a plurality of particles within the model, each particle being associated to a mineral element and a size,
• simulating transport of the introduced particles, the transport of a particle comprising moving the particle from one cell to another or depositing the particle, and
• generating, on the bottom surface or on a previously-deposited layer of sediments, a layer comprising a plurality of cells where each cell is associated to a thickness of deposited particles, and
• wherein the petrophysical parameters associated to each cell of the generated layer are computed from the mineral elements and sizes of the particles deposited in each cell.