Abstract

We are studying how bypassed oil in old, relatively shallow fields may be found with surface-sourced seismic data (SSSD), which image to about 5000 ft. We have collected and imaged SSSD in LaSalle Parish, LA, correlated these data to old well logs using resistivity based sonic models, and have performed AVA analyses. Our results show that the high temporal and spatial resolution of the SSSD allow interpretation of the shallow fluvial deposits which were either never surveyed with industry seismic data or were not adequately resolved within such data, whose collection was designed for deeper targets. Our results illustrate the advantages and capabilities of SSSD—no shot holes, no explosive permits, less risk to subsurface infrastructure, smaller surface environmental footprint, tighter shot spacing for the cost and time, and higher frequency to horizons of interest. Examples of underdrilled old fields demonstrate where remapping of well-logs coupled with targeted 2D and/or 3D SSSD may be utilized to delineate between wells and to extend facies and structure beyond existing well control to find bypassed pay.