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arXiv · 1507.07582

Complex dielectric properties of organic-rich mudrocks as functions of maturity

Rezwanur Rahman·John A. Scales·Manika Prasad
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Abstract

Complex dielectric variations can address neatly the maturity of organic-rich mudrocks. We, therefore, apply an open hemispherical cavity resonator to measure complex dielectric permitivitties of five thin sections of oil (bakken) shales (with different maturity) of $\sim$ 30 $μ$m thickness on glass-substrates around 2.15 mm thick in 100 - 165 GHz. The real part of complex dielectric permittivity ($ε_{re}$) are constant but show significant differences in magnitude based on maturity: (1) lowest, $\sim$ 1.9, for immature or early maturation stage, (2) higher than the immature one, $\sim$ 3.0 (also bundled up together), for three oil-matured stages, and (3) highest, $\sim$ 4.9, for late or overmatured stage. The conductivity ($σ_{re}$) from imaginary part of the complex dielectric constant ($ε_{im}$) emphasizes two important features of conductivity of oil shales: (1) frequency dispersion, and (2) maturity-dependence. We obtain increases of $σ_{re}$ with maturity and frequency.

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Rezwanur Rahman, John A. Scales, Manika Prasad. 2015-07-27. Complex dielectric properties of organic-rich mudrocks as functions of maturity. https://arxiv.org/abs/1507.07582

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