SEGJ Technical Conference

The physical models for evaluation of CO2 saturation by using seismic velocity

Abstract In order to evaluate amount of injected CO2 by using seismic velocity, it is necessary to determine the relationship between CO2 saturation and seismic velocity specified for each reservoir rock. For the construction of this relationship, some physical models have been proposed, such as DEMA (Dynamic Equivalent Medium Approach), BA-DEMA (Bounds Average Dynamic Equivalent Medium Approach), the Variable characteristic length model and the Modified patchy saturation model. We compare and evaluate these models for the applicability corresponding to field condition. As a consequence, the key points for the applicability of the model are seismic frequency and heterogeneity scale caused by CO2 distribution. This paper describes the summary of these models. By comparison and evaluation of those models, we intend to demonstrate key points in evaluation and application of these models.