Mineralogical effects on elastic properties and anisotropies of organic shales
- Xuan Qin (University of Houston) | De-Hua Han (University of Houston) | Fuyong Yan (University of Houston) | Luanxiao Zhao (Tongji University)
- Document ID
- Society of Exploration Geophysicists
- 2016 SEG International Exposition and Annual Meeting, 16-21 October, Dallas, Texas
- Publication Date
- Document Type
- Conference Paper
- 2016. Society of Exploration Geophysicists
- Rock physics, Anisotropy, Shale
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- 77 since 2007
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In this study, we investigate the reported ultrasonic measurements of core samples of organic shale and our lab measurements. We focus on Vp/Vs ratios, P-impedance, and velocity anisotropies for different types of organic shales. A layered model is constructed to explain why the silica-rich shales tend to have higher S-wave anisotropy and calcareous shales tend to have higher P-wave anisotropy. The modeling results of the ratio of Thomsen’s anisotropic parameters, γ/ε, remain approximately as constants in the silica-rich and calcareous shales. Hence, γ/ε ratio may be potentially treated as an indicator for mineralogical composition in shale reservoirs. We also observe linear trends between Thomsen’s parameters, ε and δ, in the calcareous shale. Additionally, ν12 and ν31, Poisson’s ratios in a transverse isotropic (TI) medium, exhibit a linear relationship in silica-rich shales and clay-rich shales, providing insights for characterizing mineralogical composition of organic shales.
Presentation Date: Tuesday, October 18, 2016
Start Time: 3:20:00 PM
Presentation Type: ORAL
|File Size||1 MB||Number of Pages||5|
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