Best Practices on Forward 4D Seismic Modelling from Dynamic Reservoir Models

Summary In this work, we discuss ways of creating realistic synthetic 4D seismic data from a simulation model of a real Brazilian sandstone reservoir. More specifically, we propose manners to define the acoustic properties in the overburden and underburden intervals, as well as to add noise to the modeled amplitudes. For that, two approaches are showed; in the first one, the non-reservoir intervals are populated with acoustic impedances derived from the seismic inversion process; in this case, inversion residuals are added as noise. In the other approach, we use constant acoustic impedance values to define the overburden and underburden intervals and add random Gaussian noise to the synthetic amplitudes. Furthermore, we show ways of calibrating the noise intensity using maps of NRMS. The 4D seismic data obtained with the use of seismic inversion results showed actual effects of reflections and acquisition problems, helping the signals' interpretation by showing the modeled and acquired data with the same noise level. With this, the interpretation of the reservoir dynamic behaviour is aimed and the simulation model accuracy is accessed, improving reservoir management.