stratigraphic trap

geology

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July 14, 2026

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A stratigraphic trap is a natural underground formation that can hold oil or natural gas. Unlike structural traps, which are formed by the bending or breaking of rock layers, stratigraphic traps are created by changes in the rock layers themselves. These changes can involve variations in porosity (the amount of empty space in the rock) and permeability (how easily fluids can flow through the rock).12

These traps occur due to sediment deposition or erosion. For example, ancient coral reefs, sandbars, or river channels buried underground can act as reservoirs. If these porous rock layers are surrounded by less permeable rocks, they can trap migrating oil and gas. Stratigraphic traps are crucial in petroleum exploration because they represent significant natural reservoirs for hydrocarbons.32

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petroleum trap
In a stratigraphic trap, variations within the rock strata themselves (e.g., a change in the local porosity and permeability of the reservoir rock, a change in the kinds of rocks laid down, or a termination of the reservoir rock) play the important role. The stratigraphic variations associated…
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In a stratigraphic trap, variations within the rock strata themselves (e.g., a change in the local porosity and permeability of the reservoir rock, a change in the kinds of rocks laid down, or a termination of the reservoir rock) play the important role. The stratigraphic variations associated…
Read More

petroleum
Stratigraphic traps
A second major class of petroleum traps is the stratigraphic trap. It is related to sediment deposition or erosion and is bounded on one or more sides by zones of low permeability. Because tectonics ultimately control deposition and erosion, however, few stratigraphic traps…
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A second major class of petroleum traps is the stratigraphic trap. It is related to sediment deposition or erosion and is bounded on one or more sides by zones of low permeability. Because tectonics ultimately control deposition and erosion, however, few stratigraphic traps…
Read More