| 摘要 |
A method of obtaining an estimate of the earliest part of a surface recorded seismogram which comprises generating a seismic shot, recording by one or more well geophones signals from said shot which have transmitted through and/or reflected from various strata of the earth, autocorrelating the z- transforms of the upgoing and downgoing waves, and determining the difference between the autocorrelated z-transforms and utilizing said difference as an estimate of the surface seismogram. A plurality of such estimates may be normalized and a central measure taken to give an enhanced estimate. The estimate obtained by the method of the invention may be deconvolved to give a band-limited estimate of the log of accoustic impedance above the top of the velocity and density logs. |
