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| Growth faults common || - || Numerous sealing fault compartments
| Growth faults common || - || Numerous sealing fault compartments
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| Shingled geometry || - || Results in bypassed oil in individual shingles
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| Increasing marine reworking of delta front || Creates increasing lateral connectivity in the delta-front sediments || -
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| Wave-dominated delta || More continuous, may have an aquifer || -
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| Fluvial-dominated delta || - || Can show low recoveries caused by labyrinthine geometry
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| Tidal-dominated delta || - || Low recoveries caused by complex geometry and numerous mud and silt baffles
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| Distributary channels form narrow sand bodies || - || May be missed by wells in fields with a large well spacing; difficult to locate injection wells
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| Distributary channel sands commonly the highest permeability facies association in deltas || Can be the most productive intervals in a delta || -
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| Stacked distributary channels || Larger sand bodies with good vertical connectivity and sweep || -
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| Mouth bars contain extensive mudstone laminae || - || Mouth bars may have poor vertical connectivity and sweep
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| Stacked mouth bars || Larger sand bodies with good vertical connectivity and sweep || -
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| Mouth bars separated vertically by shales || Individual mouth bars can be targeted by horizontal wells; shale prevents water influx from swept units above and below || Poor to no vertical connectivity between mouth bars
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| Coarser grained distributary channels cutting finer-grained delta-front sandstones || - || Can result in preferential water ingress into the delta-front area, bypassing oil in the delta-front sediments
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| Peripheral strand-plain complexes with high frequency marine shales || - || Poor vertical sweep with potential for bypassed oil
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==Deltas are often gas reservoirs==
Many deltaic reservoirs, particularly long-lived Tertiary to present-day delta areas, contain more gas than oil. This is because they can be particularly rich in coals and woody kerogen, which form gas-prone humic source material. Gas fields are found in the Mackenzie, Nile, and Irrawady deltas, for instance. Deltas can contain oil or mixed oil and gas where sandstones interfinger with a marine source rock.<ref name=Gallowayandhobday_1996>Galloway, W. E., and D. K. Hobday, 1996, Terrigenous clastic depositional systems: Applications to petroleum, coal, and uranium exploration: New York, Springer-Verlag, 489 p.</ref>