The interlayer and intralayer interference

which is commonly existing in the process of oilfield development

especially for the offshore strongly heterogeneous huge thick sandstone and conglomerate reservoirs that are not completely separated vertically

is the basis and internal cause of reservoir subdivision. In practice

interference data are primarily obtained from production logging

which shows that the interference coefficient changes with the development stage and over time. Since production logging is typically a point test

it does not capture the full cycle interference coefficient

highlighting the need for laboratory studies on interlayer and intralayer interference. The theoretical study of interference coefficient involves numerous parameters and the interference coefficient changes with time. This theory can explain the phenomenon that the overall oil production capacity of multi-layer combined production wells is lower than the cumulative amount of multi-layer production

but it fails to solve the theoretical root cause of its formation. So a one-dimensional core displacement experimental device was used for the study of the interlayer and intralayer interference. The experiment shows that for the interlayer interference

the interference coefficient gradually increases with time as water cut rises

but decreases in high water cut period. This is due to the difference in the displacement pressure gradient of each core during single flooding and combined flooding. While for the intralayer interference

the interference coefficient of oil production index is large in the early stage

and gradually decreases with the increase of water cut. The essence of the interference is that the change of seepage resistance of different reservoirs with time results in the change of reservoir flow distribution.