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What role do sheeted dikes play in forming oceanic crust?

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Earth's lithosphere and upper mantle — oceanic crust A cross section of Earth's outer layers, from the crust through the lower mantle.

Sheeted dikes play a critical role in the formation of oceanic crust by acting as the essential plumbing system for the transport of magma from underlying chambers to the seafloor.1

Located beneath the surface layer of lavas, this layer of basaltic dikes is typically more than 1 km (0.6 mile) thick. These structures are characterized by the following:1

Formation: They are subvertical fractures that form along the trend of spreading centres at oceanic ridges.1
Structure: Each dike is approximately 1 metre (3 feet) wide. They are termed "sheeted" because they abut one another’s sides, creating a continuous, layered sequence.1
Function: By serving as conduits, they allow molten rock to reach the surface, where it erupts as either pillow lavas or sheet flows, thereby contributing to the growth and renewal of the oceanic crust.1