254 Geophysics in Geothermal Exploration Conclusions and perspectives The work described in this chapter has been applied using newly generated azimuthal stacks, for which the processing sequence has been evaluated very carefully, preventing destructive steps for both AVAZ and VVAZ approaches. When both approaches seem equally acceptable, as along the Top Cretaceous event, labelling depending on the anisotropy range is proposed for AVAZ and VVAZ approaches (Figure 8.15) using cut-offs, and the result would highlight, in red, the most prospective areas outside low-energy areas and outside main seismic faults. Figure 8.15 Ellipse fitting, a powerful tool to combine maps into anisotropy estimation. The anisotropy interpretation as a fracture attribute is still a challenge. A brutal and oriented change in properties affecting impedance, such as karsts, can also induce anisotropy. As a way forward, matrix characterization and karst identification will be carried out to further understand the other possible anisotropy sources, using elastic inversion as described in the previous chapter. Still in exploration phase, the new wells to be drilled in the area will reveal key aspects to refine the anisotropy interpretation, using BHI to interpret the fault and fracture clusters to be correlated with the anisotropy results. References Adelinet M., Barnoud A., Clochard V., Ricarte P. (2013) Improved unconventional reservoir characterization using multi-azimuth stratigraphic inversion, case
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