Well-ties with log synthetic seismogram based on prestack wavefields simulation

The effects of multiples,converted-waves and the processing procedure on well-ties were not taken into account in conventional well-ties method. In order to decrease the differences of wavefield characteristic between log synthetic seismogram and nearby-well seismic trace,and improve the reliability of well-ties,a new well-ties method based on prestack wavefield simulation was proposed. Firstly,the well log was edited and the wavelet was extracted by conventional method. Secondly,the common-reflection-point gather located at the well was simulated by the reflectivity method. Thirdly,normal time difference correction and stack were applied to the simulated common-reflection-point gather. Finally,the stack trace was used as synthetic seismogram to calibrate the seismic reflections for well-ties. The results show that the consistency of synthetic seismogram and well-nearby traces was improved,and the reliability of well-ties was enhanced by using the new method.