A Spreading‐Rate Dependence for Periodic Signals Embedded in Otherwise Aperiodic Abyssal Hills

Abstract I present evidence, through an empirical pre‐whitening analysis, that periodic signals are embedded in otherwise aperiodic abyssal hills across paleo‐spreading rates ranging from 1 to 9 cm/yr (half rate). Data are comprised of archival trackline and multibeam bathymetry profiles in north and south Atlantic Oceans, Pacific‐Antarctic Ridge flanks, and north and south East Pacific Rise flanks. Detected periods vary widely, from the low tens of thousands to millions of years, and do not cluster at specific values. Up to half spreading rates of ∼4 cm/yr, periodicities are negatively correlated with spreading rate at high confidence, despite the strong scatter in results; there is no correlation at higher spreading rates. Both the strong scatter and spreading rate dependence indicate that periodicities are intrinsically generated. I hypothesize that periodic signals are controlled by volcanic processes, whereas aperiodic morphology is controlled by faulting.