Shallow and previously overlooked plays close to existing infrastructure are becoming increasingly attractive exploration targets as the energy transition unfolds. Early exploration wells often log these intervals on the way to deeper targets, and provide critical elastic rock property data needed to understand and calibrate pre-stack seismic amplitudes. In these settings, pre-stack attributes and new facies-based AVO inversion methods can improve 3D amplitude understanding, in a fraction of the time needed for traditional pre-stack inversion.
Sharp Reflections illustrates this integrated amplitude analysis approach on a look-back study of a recent exploration prospect in the Miocene-aged Utsira Formation offshore Norway. Lundin Petroleum provided all the data used in the study, and the exploration background. Sharp’s team used pre-stack seismic and limited elastic rock property information from wells to unravel complex amplitude map patterns and quantify expected amplitude response for different reservoir fill scenarios. We then used Norsk Regnesentral’s PCube+ AVO inversion to rigorously validate the geologic concept, assess gas-versus-oil likelihood, and estimate reserves. All work was completed in just a few days, illustrating the power of PreStack Pro’s highly interactive seismic analysis solutions.
Thanks to Peter Harris, Yaw Duah, Stephane Perrier, and our Lundin collaborators for contributions to the case history.