Small deviations variations of ambient pressure
from initial pressure fromarion formation pressure lead to
the exponential changes in permeability:
| LaTeX Math Block |
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| anchor | CPHWYk |
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| alignment | left |
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k=k_0 \, e^{\beta_pn_k \cdot c_r (p-p_0)} |
where
| formation compressibility |
| LaTeX Math Inline |
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| body | n_k = \frac{\ln (k/k_0)}{\ln(\phi/\phi_0)} |
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| power degree of permeability-porosity correlation |
| formation permeability at reference pressure
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| formation porosity at reference pressure |
| reference pressure, usually picked up at initial formation pressure |
The substantial reduction of formation pressure leads to shrinking a lot of numerous pore throats and massive reduction in permeability deviating from exponential.
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