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| Retention mechanism | Controlling factor | Favorable condition |
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| Surface capillary retention | Wettability, surface roughness | Large roughness, hydrophilic rock, low flow rate |
| Surface-bound water film | Surface dryness, liquid surface properties | Dry surface, strong hydrophilicity |
| Matrix pore imbibition | Physical properties, liquid type, clay and ion content | Small pores, wetting liquids, high clay/ion content |
| Fracture closure “locking” | Contact area, fracture aperture, roughness, stress | Large contact area/stress, high roughness, small aperture |
| Gravity retention | Liquid viscosity, fracture aperture, roughness, fracture height | High viscous force, large aperture |
| Viscous trapping | Fracture aperture, drive pressure, liquid viscosity | Small aperture and pressure, high viscosity |
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