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Abstract

Summary

We conducted several petrophysical measurements on forty nine core samples collected from the Jurassic and Cretaceous strata exposed at west central Lebanon to evaluate their petrophysical and elastic properties and study the effects of the depositional conditions, sediment composition, and subsequent diagenetic processes on the measured parameters. First, these rocks were petrographically studied to identify the lithofacies, porosity, and the main diagenetic features. In addition, these rocks were investigated under the scanning electron microscope (SEM) and by the X-ray diffraction (XRD) analysis to identify their mineralogy. The petrophysical measurements were performed on the core samples where porosity, permeability, bulk and grain densities were first determined, followed by measuring the seismic wave velocities. The main lithofacies of these rocks can be categorized mainly into carbonates and siliciclastics. The SEM and XRD analyses revealed that the main constituting minerals are calcite, quartz, dolomite, beside other accessory minerals. The studied rocks have generally low to moderate porosity, moderate to high bulk density, and very low permeability. The average Vp and Vs are 4263, and 2323 m/s, respectively, giving a Vp/Vs ratio of 1.83. We further calculated the elastic moduli of the studied rocks and established a number of relationships between the measured petrophysical and acoustic properties to examine their mutual interdependence and evaluate the effects of porosity, rock composition, depositional and diagenetic processes on the measured rock characteristics. We found that some samples, mainly carbonates, deviate significantly from the expected porosity-velocity and density-velocity trends. It is thought that coring-induced microcracking, originally-present micro- and intercrystalline pores in these carbonate rocks may account for these outliers.

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/content/papers/10.3997/2214-4609.201900389
2019-04-24
2024-04-27

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References

  1. Anselmetti, F. S., Eberli, G. P.
    , 1993. Controls on sonic velocity in carbonates. Pageoph, 141, No. 2/3/4.
     [Google Scholar]
  2. El Sayed, N. A., Abuseda, H., Kassab, M. A.
    , 2015. Acoustic wave velocity behavior for some Jurassic carbonate samples, north Sinai, Egypt. J. Afr. Earth Sci., 111, 14–25, http://dx.doi.org/10.1016/j.jafrearsci.2015.07.016
     [Google Scholar]
  3. Erickson, S. N., Jarrard, R. D.
    , 1998. Velocity-porosity relationships for water-saturated siliciclastic sediments. J. Geophys. Res., 103(B12), 30385–30406.
     [Google Scholar]
  4. Flügel, E.
    , 1982. Microfacies Analysis of Limestone. Springer-Verlag, Berlin, 663 p.
     [Google Scholar]
  5. Gardner, G. H. F., Gardner, L. W., and Gregory, A. R.
    , 1974. Formation velocity and density — the diagnostic basics for stratigraphic traps. Geophys., 39, 770–780.
     [Google Scholar]
  6. Gregory, A. R.
    , 1976. Fluid saturation effects on dynamic elastic properties of sedimentary rocks. Geophysics, 41, 895–921.
     [Google Scholar]
  7. Gupta, V., Sharma, R.
    , 2012. Relationship between textural, petrophysical and mechanical properties of quartzites: A case study from northwestern Himalaya. Eng. Geol., 135-136, 1–9, doi:10.1016/j.enggeo.2012.02.006
     https://doi.org/10.1016/j.enggeo.2012.02.006 [Google Scholar]
  8. Han, D. H., Batzle, M.
    , 2004. Gassmann’s equation and fluid-saturation effects on seismic velocities. Geophysics, 69, 398–405.
     [Google Scholar]
  9. Russell, B. H., Smith, T.
    , 2007. The relationship between dry rock bulk modulus and porosity — An empirical study. CREWES Res Report, 19, 1–14.
     [Google Scholar]
  10. Walley, C. D.
    , 1997. The lithostratigraphy of Lebanon: a review. Lebanese Scientific Research Reports, 10(1), 81–108.
     [Google Scholar]
  11. Wang, J.-H., Hung, J.-H., Dong, J.-J.
    , 2009a. Seismic velocities, density, porosity, and permeability measured at a deep hole penetrating the Chelungpu fault in central Taiwan. J. Asi. Earth Sci., 36, 135–145, doi:10.1016/j.jseaes.2009.01.010
     https://doi.org/10.1016/j.jseaes.2009.01.010 [Google Scholar]
  12. Wilson, J. L.
    , 1975. Carbonate facies in geologic history. Springer-Verlag, New York, 471 p.
     [Google Scholar]
  13. Yu, Ch., Sh. Ji,, Li, Q.
    , 2016. Effects of porosity on seismic velocities, elastic moduli and Poisson’s ratios of solid materials and rocks. J. Rock Mec. Geotech. Eng., 8, 35–49, http://dx.doi.org/10.1016/j.jrmge.2015.07.004
     [Google Scholar]
http://instance.metastore.ingenta.com/content/papers/10.3997/2214-4609.201900389
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Petrophysical and Geotechnical Evaluation of Mesozoic Rocks from Central Lebanon
Conference Proceedings 2019, 1 (2019); https://doi.org/10.3997/2214-4609.201900389
/content/papers/10.3997/2214-4609.201900389
/content/papers/10.3997/2214-4609.201900389
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