f Inelastic absorption effects on the integration of borehole and subface seismic data

Timing and character mismatches between borehole and surface seismic are often encountered when correlating and calibrating seismic data. Even after block shifts are applied, a good match at shallow depths can gradually deteriorate into a mis-tie of up to 20 msec in the target area. Once events have been correlated in a single well this mis-tie is often at tributed to well deviation or poor migration of the surface data. These time variant misdes pose a critical problem when a large number of wells are examined in a workstation environment. For example, wavelet matches appear to be time variant and the translation of physical parameters from one data set to the other will be wrong: In a number of cases inelastic absorption has proved to be the cause; compensation of this Q effect has provided a solution, often with the added benefit of improved vertical resolution.