The added value of WEB-AVO inversion for geothermal project development: a 2D reservoir characterization case study.

Summary Optimal and successful geothermal development depends on the identification of aquifers with good reservoir properties combined with appropriate subsurface temperatures. Uncertainties need to be kept to a minimum to achieve a robust and positive business case for investors to commit. This paper demonstrates wave-equation based AVO (WEB-AVO) inversion on pre-stack seismic data as a useful technique to better assess the feasibility of geothermal projects in low data density areas. One unique feature of this method is that it solves directly for compressibility and shear compliance, which are commonly more sensitive for reservoir property changes compared to acoustic and shear impedance. Although the technique has its limitations related to data quality and availability, it showed that it could very well be used for optimisation of a geothermal project. For a case study in the Blaricum region (the Netherlands), top, base and thickness interpretations of the targeted geothermal reservoir could be enhanced, gPOS could be uplifted, and baffles and barriers (sedimentary, diagenetic and/or structural in origin), could be better identified. Consequently, a more optimal well placement can be achieved.