Reservoir Characterization Applying High-Resolution Seismic Profiling, Rabis Creek, Denmark

Onshore reflection seismics have been used to characterize the geometry and lithology of ground‐water reservoirs. The study was carried out as a seismic sequence and facies analysis along Rabis Creek in western Denmark. A1350 m long seismic section was produced on a presumed homogeneous outwash sand plain. High resolution data to a depth of 160 m (200 msec two‐way time) were obtained along most of this section, and reflections from more than 400 m in depth were obtained locally. The seismic data have been correlated with electrical resistivity logs. The reservoir is, in contrast to the expectations, highly heterogeneous, composed of three distinguishable seismic sequences of unconsolidated sediments. Layers down to 1.5 m thick were recognized in the seismic data. The study shows that onshore reflection seismics provide a unique possibility of 2‐D reservoir scale characterization of geological structures. Combined with seismic facies and sequence analysis, seismic profiling forms a strong hydrogeological tool that may supplement traditional boring and logging methods.