1887

Abstract

Summary

Micro X-ray computed tomography was used to image confining-pressure induced changes in a dry, unconsolidated quartz sand pack while simultaneously recording ultrasonic P-wave velocities. We visually observed a reduction in porosity by more than a third as well as extensive grain damage, changes in grain size distribution and an increase in coordination number and contact radius with increasing confining pressure. We used porosity, contact number and contact radius to compute P-wave velocities with the Hertz-Mindlin contact-radius model. Our observations showed that numerous assumptions of the widely used Hertz-Mindlin model are violated in angular sediments and the model drastically overpredicts velocities.

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/content/papers/10.3997/2214-4609.201801015
2018-06-11
2024-04-20
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References

  1. Andrä, H., Combaret, N., Dvorkin, J., Glatt, E., Han, J., Kabel, M., Keehm, Y., Krzikalla, F., Lee, M., Madonna, C. et al.
    [2013] Digital rock physics benchmarks - Part I: Imaging and segmentation. Computers & Geosciences, 50, 25–32.
    [Google Scholar]
  2. Bachrach, R., Dvorkin, J. and Nur, A.
    [1998] High-resolution shallow-seismic experiments in sand, Part II: Velocities in shallow unconsolidated sand. Geophysics, 63(4), 1234–1240.
    [Google Scholar]
  3. Dvorkin, J., Derzhi, N., Diaz, E. and Fang, Q.
    [2011] Relevance of computational rock physics. Geophysics, 76(5), E141–E153.
    [Google Scholar]
  4. Madonna, C., Quintal, B., Frehner, M., Almqvist, B.S., Tisato, N., Pistone, M., Marone, F. and Saenger, E.H.
    [2013] Synchrotron-based X-ray tomographic microscopy for rock physics investigations. Geophysics, 78(1), D53–D64.
    [Google Scholar]
  5. Mindlin, R.
    [1949] Compliance of elastic bodies in contact. J. appl. Mech., 16, 259–268.
    [Google Scholar]
  6. Prasad, M. and Meissner, R.
    [1992] Attenuation mechanisms in sands: Laboratory versus theoretical (Biot) data. Geophysics, 57(5), 710–719.
    [Google Scholar]
  7. Saenger, E.H., Lebedev, M., Uribe, D., Osorno, M., Vialle, S., Duda, M., Iglauer, S. and Steeb, H.
    [2016] Analysis of high-resolution X-ray computed tomography images of Bentheim sandstone under elevated confining pressures. Geophysical Prospecting, 64(4), 848–859.
    [Google Scholar]
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