The present disclosure relates to a method for determination of a real subsoil geological formation. In at least one embodiment, the method includes receiving a model representing the real subsoil. The model includes a shore line and a fluvial formation connected to the shore line at a point of the model. The shore line divides the model into a marine zone and a continental zone. The method further includes determining a delta zone in the model based on the shore line and based on the fluvial formation, determining a stochastic trajectory in said delta zone, and determining a lobe formation in said delta zone based on the determined stochastic trajectory based on a stochastic process.