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One of the saturation from resistivity models:
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| anchor | Indonesia |
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| s_w = \left[ \frac{ \frac{1}{\sqrt{R_t}} }{ \left( \left \frac{V_{sh}^{1- 0.5 \, V_{sh}}}{\sqrt(R_w)} \right) + sqrt{ \frac{\phi_e^m}{A \cdot R_w} } \right ) } \right]^{2/n} |
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| anchor | Indonesia |
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| alignment | left |
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| \frac{1}{R_t} = \frac{\phi_e^m \, s_w^n }{A R_w} \quad \Rightarrow \quad s_w = \Big ( \frac{A}{\phi_e^m} \; \frac{R_w}{R_t} \Big) ^{1/n} |
where constant is defined by formation shaliness :| LaTeX Math Block |
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| \frac{1}{A} = 1 + \Big( \frac{V_{sh}^{2-V_{sh}}}{\phi_e} \, \frac{R_w}{R_{sh}} \Big)^{1/2} |
where | formation water saturation |
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| effective porosity |
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| shaliness |
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| specific electrical resistivity from OH logs |
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| specific electrical resistivity of formation water |
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| specific electrical resistivity of wet shales |
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| formation matrix cementation exponent | 1.5 ÷ 2.5, default value is 2 |
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| formation matrix water-saturation exponent | 1.5 ÷ 2.5, default value is 2 |
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See Also
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Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petrophysics
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