Page 41 - PVT Property Correlations
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22 PVT Property Correlations
FIGURE 2.10 Saturated gas condensate and its associated equilibrium oil-phase diagrams.
FIGURE 2.11 API gravity of stock-tank liquid versus C7 1 mole % for oil fluids.
Some classifications use API gravity of stock-tank liquid as one of the
criteria to distinguish reservoir-fluid types. Fig. 2.11 represents a plot of API
gravity of stock-tank oil versus C7 1 mole %. Although the plot shows a
general trend of decreasing API gravity with increasing C7 1 mole %, the
large variation in API gravity value hinders its use as a distinctive criterion.
For low-GOR oils, the API gravity can range from 10 to 40 API. For black
