Journal : Acta Geophysica
Article : New petrophysical model describing the pressure dependence of seismic velocity

Authors :
Bogusz, J.
Centre of Applied Geomatics, Military University of Technology, jbogusz@wat.edu.pl,
Saibi, H.
Laboratory of Exploration Geophysics, Department of Earth Resources Engineering, Faculty of Engineering, Kyushu University, Fukuoka, Japan, saibi-hakim@mine.kyushu-u.ac.jp,
Verbanac, G.
University of Zagreb, Faculty of Science, Department of Geophysics, Zagreb, Croatia, verbanac@irb.hr,
Mustasaar, M.
Department of Geology, University of Tartu, Tartu, Estonia, mario.mustasaar@ut.ee,
Dobróka, M.
Department of Geophysics, University of Miskolc, Egyetemvaros, Miskolc, Hungary, dobroka@uni-miskolc.hu,
Abstract : Seismic data are increasingly applied to predict the characteristics of reservoirs, as their quality improves. Since the change of pressure is a major component in exploitation of reservoirs, a thorough understanding of the influence of pressure on seismic velocity is also important. In this study we introduce the first results of the developed petrophysical model which describes the pressure dependence of seismic velocity. The model is based on the idea that microcracks in rocks open and close under the change of pressure. Laboratory measurements are presented on several sandstone samples. Longitudinal wave velocities were measured at various incremental pressures increased from 0 to 20 MPa. During the measurements, the pulse transmission technique was used and the parameters of the model were determined by using a linearized inversion method. The inversion results proved that the proposed petrophysical model well applies in practice.

Keywords : pressure, seismic velocity, petrophysical model, microcraks,
Publishing house : Instytut Geofizyki PAN
Publication date : 2012
Number : Vol. 60, no. 2
Page : 371 – 383

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DOI :
Qute : Bogusz, J. ,Saibi, H. ,Verbanac, G. ,Mustasaar, M. ,Dobróka, M. ,Dobróka, M. , New petrophysical model describing the pressure dependence of seismic velocity. Acta Geophysica Vol. 60, no. 2/2012
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