Creating virtual receivers from drill-bit noise

Creating virtual receivers from drill-bit noise

Liu, Y.
Draganov, D.S.
Wapenaar, C.P.A.
Arntsen, B.

Civil Engineering and Geosciences

Geoscience & Engineering

2015-12-31

In the field of seismic interferometry using noise, surface waves and body waves between receivers have been retrieved by crosscorrelating recordings of uncorrelated noise sources to extract useful subsurface information. When the positions of the noise sources are known, inter-source interferometry can be applied to retrieve the wavefileds between sources, thus turning sources into virtual receivers. Previous applications of this form of interferometry assume impulsive point sources or transient sources with similar signatures. We investigate the requirements of applying inter-source seismic interferometry using drill-bit noise to retrieve the reflection responses at those positions. We show that an accurate estimate of the source function is essential for such application. The preprocessing involves using standard seismicwhile-drilling procedures, such as pilot crosscorrelation and pilot deconvolution to remove the drill-bit signatures in the data, and then applying crosscorrelation interferometry. Provided that pilot signals are reliable, drill-bit data can be redatumed from surface to the depth of boreholes using this inter-source interferometry approach without any velocity information of the medium. We show that a well-positioned image below the borehole can be obtained with just a simple velocity model using these reflection responses. We also discuss some of the practical hurdles that restrict its application offshore.

http://resolver.tudelft.nl/uuid:64f2fc04-f957-410d-bc10-a7b285ef4f06

EAGE

77th EAGE Conference and Exhibition 2015, Madrid, Spain, 1-4- June 2015

Institutional Repository

conference paper

(c) 2015 The Author(s)