Collective term for oil, condensate and natural gas and their mixtures, normally encountered in subsurface reservoirs.
Its composition is dominated by pure hydrocarbons (usually Alkanes, Naphthenes, Aromatics, Asphaltics) and may also include the other organic and inorganic chemical substances (like carbon dioxide, nitrogen, hydrogen sulfide, helium etc.).
Table 1.C Example of composition omposition of several reservoir fluids (in mol %)
Component or Property | Dry Gas | Wet Gas | Condensate | Volatile Oil | Black Oil |
---|---|---|---|---|---|
CO2 | 0.10 | 1.41 | 2.37 | 1.82 | 0.02 |
N2 | 2.07 | 0.25 | 0.31 | 0.24 | 0.34 |
C1 | 86.12 | 92.46 | 73.19 | 57.60 | 34.62 |
C2 | 5.91 | 3.18 | 7.80 | 7.35 | 4.11 |
C3 | 3.58 | 1.01 | 3.55 | 4.21 | 1.01 |
i C4 | 1.72 | 0.28 | 0.71 | 0.74 | 0.76 |
n C4 | — | 0.24 | 1.45 | 2.07 | 0.49 |
i C5 | 0.50 | 0.13 | 0.64 | 0.53 | 0.43 |
n C5 | — | 0.08 | 0.68 | 0.95 | 0.21 |
C6s | — | 0.14 | 1.09 | 1.92 | 1.16 |
C7+ | — | 0.82 | 8.21 | 22.57 | 56.40 |
GOR (SCF/STB) | ∞ | 69,000 | 5965 | 1465 | 320 |
OGR (STB/MMSCF) | 0 | 15 | 165 | 680 | 3125 |
γAPI | — | 65.0 | 48.5 | 36.7 | 23.6 |
M7+ | — | 132 | 184 | 240 | 274 |
γ7+ | — | 0.750 | 0.816 | 0.864 | 0.920 |
See Also
Petroleum Industry / Upstream / Subsurface E&P Disciplines / Petroleum Geology / Petroleum Reservoir Fluids