Using time domain seismic data for history matching processes

Sophisticated workflows have been designed to build reservoir models consistent with geology, production history, and seismic attributes. The seismic attributes are usually given as functions of depth on the vertical axis, which makes their integration relatively straightforward because reservoir grids depend on depth too. This approach requires that the velocity model used to convert the seismic attributes from the time domain to depth is fixed, whatever perturbation is subsequently applied to the geological model during the history matching process. Thus, the seismic attributes are converted only once from time to depth before performing history matching. As an alternative, we propose to design workflows that integrate seismic attributes given as functions of time instead of depth. This means that workflows must simulate seismic responses in the time domain. As fluid flow simulators yield saturations and pressures over the reservoir grid, the corresponding simulated seismic responses are first computed against depth. Then they are converted from depth to time using the high-resolution velocity model derived from the petro-elastic model. With this method, the depth to time conversion step is fully integrated in the history matching loop. A numerical example is presented to illustrate the potential of the proposed methodology.