Wireless Electrical Resistivity Tomography System for CO2 Sequestration Monitoring

Geologic carbon sequestration has become an effective technology for reducing atmospheric levels of CO2 by capturing emissions and injecting them into underground geologic formations where they can be permanently isolated. In order to assure that the CO2 is effectively sequestered for long periods of time and to reduce the likelihood of local environmental impacts, cost-effective methods are needed to characterize potential sequestration reservoirs and to determine the extent, location, and nature of leaks from these reservoirs. Electrical Resistance Tomography (ERT) is a geophysical tool that has been used successfully to image the electrical resistivity of the subsurface. In particular, ERT is especially sensitive to fluid content in pores. This project will develop technology for using ERT to monitor the movement of sequestered CO2, by measuring changes in the electrical resistivity of the subsurface, both in the saturated and vadose zone. The proposed ERT system will consist of many inexpensive, self-contained units that would communicate with each other through a distributed wireless network. The capital expense of such a system would be relatively small. Operating expenses, once the system is automated, also would be small. Commercial Applications and other Benefits as described by the awardee: Carbon sequestration is becoming recognized as an effective technology for the mitigation of excessive CO2 emissions. With continued regulatory enforcement and tax incentives, CO2 sequestration monitoring could become a multi-billion dollar market