1887

Abstract

Summary

Fractures usually spread over various scales and have a strong influence on rock properties. We investigate seismic velocity and anisotropy in fractured media with different fracture sizes. Using synthetic rocks with controlled fracture geometries, we create a set of rocks with fracture sizes 2mm, 3mm and 4mm, and fracture densities 4.8%, 4.86% and 4.8% respectively. Fracture thickness is 0.06mm. P and S wave velocities are measured at 0.5 MHz while the rock samples are saturated by water. The laboratory observations proved that rocks containing different scale fractures can show different strengths of seismic anisotropy even with the same fracture density. While a few large fractures and many small fractures can have the same fracture density, small scale fractures cause a lower seismic wave velocity compared with large fractures. The theoretical predictions on shear wave anisotropy, as well as the P wave anisotropy in air saturation, are not affected by fracture size. In contrary, the measured results show anisotropy are apparently affected by the various size fractures.

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/content/papers/10.3997/2214-4609.201701107
2017-06-12
2024-03-28
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References

  1. Barbier, M., Hamon, Y., Callot, J.-P., Floquet, M. and Daniel, J.-M.
    [2012] Sedimentary and diagenetic controls on the multiscale fracturing pattern of a carbonate reservoir: The Madison Formation (Sheep Mountain, Wyoming, USA). Marine and Petroleum Geology29(1), 50–67.
    [Google Scholar]
  2. Berryman, J.
    [1979] Long - wave elastic anisotropy in transversely isotropic media. GEOPHYSICS44(5), 896–917.
    [Google Scholar]
  3. Carcione, J., Kosloff, D. and Behle, A.
    [1991] Long - wave anisotropy in stratified media: A numerical test. GEOPHYSICS56(2), 245–254.
    [Google Scholar]
  4. Ding, P., Di, B., Wang, D., Wei, J. and Li, X.
    [2014a] P and S wave anisotropy in fractured media: Experimental research using synthetic samples. Journal of Applied Geophysics109(0), 1–6.
    [Google Scholar]
  5. Ding, P., Di, B., Wei, J. and Li, X.
    [2014b] Experimental Observations of the Effects of Fracture Scale on Elastic Wave Velocity and Anisotropy. 76th EAGE Conference and Exhibition 2014.
    [Google Scholar]
  6. Guéguen, Y. and Sarout, J.
    [2009] Crack-induced anisotropy in crustal rocks: Predicted dry and fluid-saturated Thomsen’s parameters. Physics of the Earth and Planetary Interiors172(1–2), 116–124.
    [Google Scholar]
  7. Hudson, J. A., Liu, E. and Crampin, S.
    [1996] The mechanical properties of materials with interconnected cracks and pores. Geophysical Journal International124(1), 105–112.
    [Google Scholar]
  8. Maultzsch, S., Chapman, M., Liu, E. and Li, X. Y.
    [2003] Modelling frequency - dependent seismic anisotropy in fluid - saturated rock with aligned fractures: implication of fracture size estimation from anisotropic measurements. Geophysical Prospecting51(5), 381–392.
    [Google Scholar]
  9. Mukerji, T., Mavko, G., Mujica, D. and Lucet, N.
    [1995] Scale - dependent seismic velocity in heterogeneous media. GEOPHYSICS60(4), 1222–1233.
    [Google Scholar]
  10. Shafiro, B. and Kachanov, M.
    [1997] Materials with fluid-filled pores of various shapes: Effective elastic properties and fluid pressure polarization. International Journal of Solids and Structures34(27), 3517–3540.
    [Google Scholar]
  11. Shapiro, S. A. and Kneib, G.
    [1993] Seismic Attenuation By Scattering: Theory and Numerical Results. Geophysical Journal International114(2), 373–391.
    [Google Scholar]
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