Geophysical Monitoring For Geologic Carbon Storage

This monograph covers the state-of-the-art geophysical techniques for monitoring CO₂ storage within subsurface geologic formations, such as oil fields, gas fields, saline formations, unmineable coal seams, and saline-filled basalt formations. Geophysical monitoring techniques exploit geophysical signals from CO₂ reservoirs or target monitoring regions such as potential leakage paths, to inform where the CO₂ plume is and how the integrity of cap rock seals are. These signals can be from passive sources or active sources. Geophysical monitoring employs sensors in boreholes, or on the Earth's surface, or above the Earth's surface to acquire geophysical signals. Geophysical monitoring is to use these information to infer the movement and the fate of injected CO₂ within three-dimensional subsurface. Most geophysical monitoring techniques are non-invasive, and are to detect subsurface changes caused by CO₂ movement in kilometers away from the sensors. High-resolution and high-fidelity geophysical monitoring techniques are necessary to ensure safe and long-term geologic carbon storage. In addition, this monograph also provides some applications of geophysical monitoring techniques at a number of large-scale field demonstration projects. These applications demonstrate the practical capabilities of geophysical monitoring techniques.