Enhanced reservoir monitoring using coupled electromagnetics and flow modeling

Abstract

Remote time lapse monitoring of reservoirs can provide valuable information to meet production goals such as enhanced oil recovery and CO2 sequestration. Remote monitoring requires technology that can reliably detect movement and changes in the reservoir during production and flooding events. An injection event can be modeled and monitored using flow simulation software and electromagnetic (EM) data. First the injection event is simulated to predict the fluid flow. The modeling simulates multiphase flow in porous media and is based on a fully implicit solution of the pressure saturation formulation. The code is able to simulate any fluid flow, such as water, CO2 and/or oil within the reservoir given an injection rate and hydraulic parameters. While EM geophysical data can be inverted on their own, due to the non-uniqueness of the problem, adding additional information to the inversion can greatly improve results. To enhance the inversion model, the outputs of the flow simulation software are used as constraints for the electromagnetic inversions. Once the constraint model has been constructed, the EM data are then inverted in 3D. The changes in the inverted conductivity models image the injection event over time. The final product is a remote monitoring system for reservoirs and injection events that can reliably assess real-time reservoir conditions to meet production goals.