Development of Autonomous Nodal Electromagnetic Measurement System for Geophysical Monitoring of Geologic Carbon Storage Processes

CO2 sequestration projects, when deployed at scale, must move beyond prototype systems dependent of teams of specialist scientists and become supportable industrial processes. One portion of the of this industrial process is the monitoring of the subsurface conditions of the saline aquifers undergoing CO2 injection. Novel deployments utilizing borehole transmitters are a potential solution to injection of current close to the point of CO2 delivery, enhancing the detectability of the target.Our project will define the required adaptations of currently available electromagnetic instrumentation and workflows that will enable turn-key operation, a critical component in the safe and cost-effective of these installations. These instruments are routinely utilized in short-term deployments utilizing specialist operations staffs for applications such as the monitoring of hydrofracturing. Our work in Phase 1 will focus on using electromagnetic modeling tools, combined with field noise measurements, to build fieldable prototype instruments.We will utilize three-dimensional numerical simulation tools to model the electromagnetic response of changing physical properties of the subsurface created by CO2 injection. Models based on the geological situations and known electromagnetic noise at two existing Carbon-Safe projects will be used to define acquisition parameters for electromagnetic monitoring of the subsurface using transmitter dipoles that utilize steel well casing as transmitters coupled to an array of surface receivers.With these survey designs and numerical models as our guide, we will define, design, and prototype modifications to existing geophysical instruments. Critical to the deployment and operation of electromagnetic systems monitoring systems is the definition of effective telemetry, safety systems for the data collection, effective transfer of current into the subsurface. Given the ten-fold increase Carbon Capture, utilization, and sequestration, (Council on Environmental Quality Report to Congress on Carbon Capture, Utilization, and Sequestration, 2021) the manufacture, installation, effective monitoring of these injection processes at these sites is a significant commercial opportunity. The monitoring tools envisioned in this project could be adapted to other critical infrastructure monitoring opportunities including saltwater intrusion into groundwater supply and levee monitoring or other monitoring applications in which metallic cased wells are in contact with the target fluid phase.