Zero-Offset VSP Monitoring of CO₂ Storage: Impedance Inversion and Wedge Modelling at the Ketzin Pilot Site

Figure 9

Result of the band limited impedance inversion of 3D surface seismic (inline 1172) and zero-offset VSP converted to P-wave velocities. The stacked traces of the zero-offset VSP data (measured and modelled) are plotted side by side and inserted at the intersection of inline 1172 with the well. From top to bottom: baseline, repeat, and difference (repeat minus baseline) in percent of the baseline velocity. The VSP data of the left column is bandpass filtered with corner frequencies of 10–20–80–100 Hz; the VSP data of the right column is bandpass filtered with corner frequencies of 10–20–50–70 Hz. The black lines mark the positions of the K2 (upper line), the top, and bottom of the reservoir (middle and bottom line).