Line 40: |
Line 40: |
| :<math>\mbox{r} = \frac{2\gamma \cos \Theta}{\mbox{P}_{\rm c}}</math> | | :<math>\mbox{r} = \frac{2\gamma \cos \Theta}{\mbox{P}_{\rm c}}</math> |
| | | |
− | Capillary pressure for a given S<sub>w</sub> can also be converted to an approximation of height above free water (''h'') within a reservoir system. From a capillary pressure curve at a given S<sub>w</sub>, we read the capillary pressure and multiply it by a factor that converts P<sub>c</sub> to [[buoyancy pressure]] (P<sub>b</sub>). If the conversion factor is not known, we use 0.4 for gas and 0.7 for oil. | + | Capillary pressure for a given S<sub>w</sub> can also be converted to an approximation of height above [[free water level|free water]] (''h'') within a reservoir system. From a capillary pressure curve at a given S<sub>w</sub>, we read the capillary pressure and multiply it by a factor that converts P<sub>c</sub> to [[buoyancy pressure]] (P<sub>b</sub>). If the conversion factor is not known, we use 0.4 for gas and 0.7 for oil. |
| | | |
| ==Using p<sub>c</sub> to estimate ''h'' and ''r''== | | ==Using p<sub>c</sub> to estimate ''h'' and ''r''== |
Line 65: |
Line 65: |
| [[file:predicting-reservoir-system-quality-and-performance_fig9-13.png|300px|thumb|{{figure number|3}}Example of a mercury capillary pressure test.]] | | [[file:predicting-reservoir-system-quality-and-performance_fig9-13.png|300px|thumb|{{figure number|3}}Example of a mercury capillary pressure test.]] |
| | | |
− | Using the curve in [[:file:predicting-reservoir-system-quality-and-performance_fig9-13.png|Figure 3]], if S<sub>w</sub> = 20% (point 1), then the mercury capillary pressure (P<sub>c</sub>) that must be overcome to enter pore throats at that point on the curve is [[pressure::200 psi]] (point 2). Converting mercury P<sub>c</sub> to hydrocarbon column height (''h''): | + | Using the curve in [[:file:predicting-reservoir-system-quality-and-performance_fig9-13.png|Figure 3]], if S<sub>w</sub> = 20% (point 1), then the mercury capillary pressure (P<sub>c</sub>) that must be overcome to enter pore throats at that point on the curve is [[pressure::200 psi]] (point 2). Converting mercury P<sub>c</sub> to [[hydrocarbon column]] height (''h''): |
| | | |
| :<math>\mbox{h} = 200 \mbox{ psi} \times 0.7 = 140 \mbox{ ft of oil column}</math> | | :<math>\mbox{h} = 200 \mbox{ psi} \times 0.7 = 140 \mbox{ ft of oil column}</math> |
Line 89: |
Line 89: |
| [[Category:Predicting the occurrence of oil and gas traps]] | | [[Category:Predicting the occurrence of oil and gas traps]] |
| [[Category:Predicting reservoir system quality and performance]] | | [[Category:Predicting reservoir system quality and performance]] |
| + | [[Category:Treatise Handbook 3]] |