The resulting synthetic seismic differences (Fig. 8) of both the 34 °C and 38 °C options look very similar and also show some similarity to the real data, also shown in Fig. 8. The synthetic difference (repeat-base) seismograms from near the top of the reservoir agree reasonably well with the real difference seismograms (repeat-base) for the Ktzi201/2007 and Ktzi200/2007 wells reported by Ivanova et al. (2012). However, obvious disagreements are found at the Ktzi202/2007 well, which may be due to the fact that the velocity model used at this location is not sufficiently correct. Seismic amplitude differences between the 38 °C and 34 °C scenarios correspond to less than 1% of the amplitude values of the baseline (Fig. 8). Since the normalized root mean square (NRMS) differences in the 3D time-lapse data are greater than 10% (Kashubin et al., 2011) these temperature effects in the reservoir will not be resolvable with surface seismic methods at the Ketzin site.
option
34 °C
°C
option
38 °C
°C
scenario
38 °C
°C
scenario
34 °C
°C
amplitude values of the baseline
Seismic amplitude differences between the 38 °C and 34 °C scenarios
less than 1%
%
normalized root mean square (NRMS) differences
greater than 10%
%