In many practical cases the pore compressibility can be considered as independent on reservoir pressure variation:
| LaTeX Math Inline |
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| body | c_r(p) = c_r = \rm const |
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|
.
But in case the reservoir pressure is changing substantially one may need to account for the effect it takes on pore compressibility.
The model usually relates pore compressibility
to a given pressure
and
initial pore compressibility at
initial formation pressure .
| Name/Author | Scope |
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| LaTeX Math Block |
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| anchor | Dobrynin |
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| alignment | left |
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| \displaystyle c_r(p) = c_{ri} \cdot \frac{ \ln \left( \frac{ p_n }{p_{\rm max}} \right) }{ \ln \left( \frac{p_{ni}}{p_{\rm max}} \right) } |
| LaTeX Math Block |
|---|
| p_n = p_{\rm min} + 1.75 \cdot \phi^{0.51} \cdot (p_{\rm max} - p) |
| LaTeX Math Block |
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| p_{ni} = p_{\rm min} + 1.75 \cdot \phi^{0.51} \cdot (p_{\rm max} - p_i) |
|
Dobrynin | Wide pressure range: pmin = 1 MPa < p < pmax = 200 MPa
|
See also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petrophysics / Geomechanical Rock Modelling / Pore compressibility
