Hydrocarbon migration

Nearly all reservoirs are water bearing prior to hydrocarbon charge. As hydrocarbons migrate into a trap they displace the water from the reservoir, but not completely. Water remains trapped in small pore throats and pore spaces. In 1942 Arch/ e developed an equation describing the relationship between the electrical conductivity of reservoir rock and the properties of its pore system and pore fluids. 

Schumacher, D. 1996. Hydrocarbon-induced alteration of soils and sediments. In Schumacher, D. Abrams, M.A. (eds.), Hydrocarbon migration and its near-surface expression AAPG Memoir, 66, 71-89. 

FIGURE 5.3 Stages of subsurface hydrocarbon migration. (After Schwille, 1967.)... 

Similar studies done by Hall et al. (1984) on hydrocarbon of lower API gravities (i.e., gravities between 34 and 40°) show that specific retention for more viscous hydrocarbons can range between 35 to 50% of the pore volume for fine sands with porosities of approximately 30%. The loss due to retention in the aquifer as the hydrocarbon migrates to the recovery well can be significant. Wilson and Comad (1984) claim that residual losses are much higher in the saturated zone (i.e., capillary zone) than in the unsaturated zone. 

Schowalter, T.T. Mechanics of secondary hydrocarbon migration and entrapment,, 4 ssoc. Pet. Geol. Bull., 63(5) 723-760,1979. 

Figure 8.38. Summary of diagenetic events affecting Helderberg Group rocks in the central Appalachians. Hydrocarbon migration occurred during deep burial and development of quartz overgrowths in the oil-generative window of Figure 8.37, and at a temperature of about 180 to 220°C. (After Dorobek, 1987.)...

Liu X., Fehn U., and Teng R. T. D. (1997) Oil formation and fluid convection in Railroad Valley, NV a study using cosmogenic isotopes to determine the onset of hydrocarbon migration. Nucl. Instr. Meth. Phys. Res. B123, 356—360. 

PameU J., Honghan C., Middleton D., Haggan T., and Carey P. (2000) Significance of fibrous mineral veins in hydrocarbon migration fluid inclusion studies. J. Chem. Explor. 69-70, 623-627. 

Two types of local groundwater flow systems may develop in sedimentary basins at depth ranges of interest for studies of hydrocarbon migration and accumulation flow systems driven by buoyancy (Section 2.4.1) and those driven by osmosis (Section 2.4.2). 

Leythaeuser and Poelchau, 1990 Mackenzie et al., 1987, 1988). The pressure-driven separate phase hydrocarbon migration is treated in Section 3.2.2. 

Primary hydrocarbon migration involving active groundwater flow... 

Three possible modes of primary hydrocarbon migration involving groundwater movement, are described below ... 

Different primary migration mechanisms are probably responsible for the transport of hydrocarbons through the hydrocarbon-generating source rocks in sedimentary basins. The three major mechanisms of primary hydrocarbon migration seem to be ... 

Secondary hydrocarbon migration is the movement of hydrocarbons after expulsion from a source rock through carrier and reservoir rocks or fault and fracture systems. 

Secondary hydrocarbon migration under hydrostatic conditions... 

Secondary hydrocarbon migration generally occurs through water-saturated sedimentary rocks, i.e. through rocks that are water-wet. As water is generally considered a perfect wetting fluid (Schowalter, 1979), the contact angle 0 in Equation 4.14 for hydrocarbon-water-rock systems can be taken to be zero. If, in addition, the hydrocarbon-water interface is assumed to be spherical, then Equation 4.14 becomes identical with Equation 4.13. 

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