How do sediment ages provide evidence for seafloor spreading?

Sediment ages provide critical evidence for seafloor spreading by demonstrating that the ocean floor is geologically young and systematically changes in age relative to its distance from oceanic ridges.

As new oceanic crust forms at the ridge crests through volcanic activity, it is pushed laterally away from the center. Consequently, marine sediments found on the seafloor become progressively older and thicker the further they are from the ridge axis.12

This pattern is supported by the following observations:
* Age Limits: No deep-sea sediments older than approximately 200 million years have been recovered, which contradicts earlier theories regarding the permanency of ocean basins.12
* Sedimentation: Fresh basaltic lavas exposed at ridge crests are progressively buried by accumulating sediments as the crust moves away, creating a clear chronological record of the seafloor's expansion.23

By analyzing these sedimentary core samples, scientists can reconstruct the history of plate movements and confirm that the seafloor is continuously renewed at spreading centers.24