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| Characteristic | Type | Distribution location | Remaining oil occurrence |
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| Sedimentary facies transition | Wedge-shaped inlaid pinch-out shielding type | Overflow bank sand and river mouth bar of river transformation | Wedge-shaped |
| Flowing around interlayer and lamellar retention type | Falling silt layer in channel and interdistributary bay | Interval stratification |
| Bay shielding flaky retention type | Curved and straight river point bar | Flaky-shaped |
| Splicing edge of cutting channel type | River mouth bar, braided beach, and parallel port beach | Shaped like channel-edge |
| Heterogeneity | Stacking and cutting top enrichment type | River mouth bar with stacked or cut channels | Layered |
| High permeability fingering and low permeability retention type | Dendritic and network braided main channel | Finger-shaped |
| Uneven displacement of parallel high and low permeability | Channels of different thickness/types on the well | Original occurrence |
| Tectonic genesis | Fault barrier pinch-out enrichment type | Updip part of fault barrier | Rhombic |
| Microstructural undulation enrichment type | Fault cutting structural trap | Potato-shaped |
| Development mode | Squeezing pie type driving energy | Rings parallel to the gas cap | Pie-shaped |
| Insufficient driving energy | Stay away from edge and bottom water and injection wells | Original occurrence |
| Bottom water coning surrounded retention type | Around the bottom water cone | Eave-shaped |
| Development well pattern | Imperfect well pattern resulted inter and well retention | Single sand body out of well pattern control | Original occurrence |
| Insufficient displacement resulted retention | Production well away from injection well | Original occurrence |
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