Array Electromagnetics for Reservoir Monitoring

Geophysical methods are key for characterizing geologic formations and monitoring fluids within the reservoir. Electromagnetic (EM) methods, in particular, are sensitive to the changes of the reservoir fluids by measuring the bulk resistivity. Therefore, they are preferred for reservoir monitoring and geothermal exploration applications. A field-tested EM reservoir monitoring workflow, including 3D feasibility and field noise measurements at the study areas, has been implemented. The result of the workflow is an optimized survey configuration combined with the best performing sensors for an array system that can send recorded data to the cloud in real-time for a 24- hr turnaround for quality assessment. This remote assessment allows crews without experience in EM methods to efficiently carry out operations, increasing the EM methods development for global operations. This presentation includes examples of the workflow application to waterflood and CO2 storage monitoring. These examples validate our approach and demonstrate the value of EM methods for injection monitoring.