Large-Scale Geological Carbon Sequestration - Introduction to Carbon Capture and Sequestration - page 505

Figure 10.5.7 InSAR monitoring
Sketch of the concept and use of InSAR for monitoring small vertical motions over rela-
tively large areas. Reproduced with permission from the Geodesy and Seismology
Group, University of Miami.
overlying formations which causes surface uplift. These small surface
uplifts can be detected using InSAR. The corresponding subsidence within
the gas reservoir (west and south of wells KB-501 and KB-502, respec-
tively) and in wadis undergoing erosion from streamfl ow (southwest part of
the fi gure) shows up as positive range velocity (increasing distance to satel-
lite). The uplift detected by InSAR refl ects the pressurization-induced defor-
mation caused by injection rather than the CO 2 phase saturation typically
detected by seismic methods. InSAR may be complicated by vegetation
and other land surface changes in more vegetated, farmed, or populated
areas, giving rise to increased reliance on engineered point scatterers.
Surface gas fl ux (eddy-covariance and chamber
methods)
Another class of monitoring methods at sequestration sites is surface
monitoring to detect and locate CO 2 leakage into the atmosphere. A wide