Document Type : Research Paper

Authors

1 M.S. Student, Institute of Geophysics, University of Tehran, Tehran, Iran

2 Associate Professor, Institute of Geophysics, University of Tehran, Tehran, Iran

3 Professor, Institute of Geophysics, University of Tehran, Tehran, Iran

Abstract

Seismic well tying is a crucial part of the interpretation phase in exploration seismology. Tying wells usually involves forward modeling a synthetic seismogram from sonic and density logs and then matching the obtained synthetic seismogram to the seismic reflection data. A huge amount of time is required to deal with it, yet the outcome signal may not be satisfying and may be suffering a low cross correlation between the seismic signal and the synthetic one; it also requires a high quality synthetic trace. Another problem with the so-called manual tying is that the tying process is not repeatable, indicating that one can rarely obtain the same stretched and squeezed signal if the tying procedure is repeated. In recent years, some researchers have used the dynamic time warping (DTW) method to address well tying problems. They have obtained good results according to the correlation between the seismic signal and the warped synthetic signal. This research demonstrates that the result will be better if filtering is applied before tying, and then the warped signal is smoothed. We also propose a simpler algorithm for extracting a warped signal from the warping curve and the original synthetic trace, which gives rise to better performance for well tying.

Highlights

  • A simple algorithm, which needs a fewer number of calculations, was proposed for extracting a warped signal from the warping curve and an original synthetic trace.
  • Synthetic seismograms could be created by performing basic calculations on travel-time functions.
  • A Ricker wavelet was estimated and then convolved with reflection series to obtain an initial synthetic signal.
  • The employed method is more powerful in comparison to other strategies for seismic to well tying.

Keywords

Main Subjects

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