A High-Sensitivity Three-Component Accelerometer for the Seismic Monitoring of CO2 Geological Sequestration

A highly sensitive four-cantilever beam three-component (3C) fiber grating accelerometer is proposed to meet the seismic monitoring requirements of CO2 geological storage. The 3C accelerometer is properly arranged and encapsulated with three identical single-component sensors in a cylindrical shell. Theoretical and sensing structure simulations of the accelerometer coincide with the experimental results. The resonance frequency of the designed accelerometer is 195 Hz, the operating frequency bandwidth is 5–140 Hz, and the sensitivities in the X-, Y-, and Z-directions reach 1248.9, 1267.9, and 1270.4 pm/g, respectively, and the lateral interferences are all less than 2%. The excellent performance of the accelerometers enables multidimensional and high-quality seismic wave information acquisition; thus accelerometers could be used to monitor CO2 geological sequestration, dynamic $\text {CO}_{{2}}$ injection processes, and interactions between CO2 and geological formations.