How does a propagating rift change an oceanic spreading centre?

A propagating rift is a geologic phenomenon that alters the configuration of an oceanic spreading centre by causing one branch of the ridge to lengthen at the expense of another across a transform fault.1

As the rift and its associated fault propagate—moving at rates one to five times faster than the surrounding seafloor spreading rate—it fundamentally reorganizes the ridge geometry. This process leaves distinct physical evidence on the seafloor, including:1

• Chevron patterns: The propagation creates characteristic chevron-shaped patterns in magnetic anomalies.1
• Seafloor grain: The grain of the seafloor topography is altered, creating features that resemble the wake of a boat.1

This mechanism allows spreading centres to shift their positions and evolve over time, effectively reconfiguring the boundaries where new oceanic crust is generated.1