History-Matching Production and Seismic Data in a Real Field Case Using the Ensemble Smoother With Multiple Data Assimilation

Abstract

Abstract In a recent paper, we introduced a data assimilation procedure based on the application of the ensemble smoother (ES) with multiple data assimilation (MDA). The method, which has the acronym ES-MDA, was theoretically motivated by the equivalence between single and multiple data assimilation for the linear-Gaussian case and an approximate relationship between ES and one iteration of the Gauss-Newton method. ES-MDA is easy to combine with any commercial simulator, in fact, much easier than it is to couple the ensemble Kalman filter (EnKF) with a commercial simulator. Here, we apply EnKF and ES-MDA to generate multiple realizations of the porosity, net-to-gross ratio (NTG) and permeability fields by history matching production and seismic impedance data (3D and 4D) in a turbidite reservoir in the Campos Basin. 3D seismic data are integrated first and then 4D and production data are assimilated together, either simultaneously with ES-MDA or sequentially in time with EnKF.