Monitoring fluid saturation in reservoirs using time‐lapse full‐waveform inversion

Monitoring the rock-physics properties of subsurface is great importance for reservoir management. For either oil and gas applications or CO2 storage, seismic data are a valuable source information tracking changes in elastic which can be related to fluids saturation pressure within reservoir. Changes estimated with time-lapse full-waveform inversion. properties, such as saturation, inversion usually two-step process: first, inversion, then, However, multiparameter prone crosstalk between parameter classes across different vintages. This leads leakage from one class another, which, turn, introduce large errors parameters. To avoid inaccuracies caused by strategy, we reformulate estimate directly properties. Using Gassmann's model, adopt new parameterization containing porosity, clay content, water saturation. In context monitoring, assumed induced fluid substitution only. The porosity content thus kept constant during We compare this usual density-velocity benchmark models. Results indicate that proposed eliminates parameters vintages, leading more accurate estimation changes. also show using based on monitored accurately.