Analysis of ocean floor abyssal hill morphology to infer seafloor spreading evolution

Abyssal hills (AHs), formed along mid-ocean ridges by normal faults and volcanic activity, can potentially provide constraints on past seafloor spreading rates, directions and the geometry of spreading ridges. However, the morphology of AHs still remains mostly unexplored. Previous studies have examined AH morphology and showed that the shape of AHs is related to spreading rate. However, these studies have simultaneously examined wide regions therefore averaged out temporal changes in the tectonic processes that shaped them. We have developed a new automated approach for studying the shape of AHs that allows detailed temporal investigation of the tectonic processes acting along the ridges. We verified our approach along the sediment-free Mid Atlantic Ridge, the South East Indian Ridge and the East Pacific Rise by examination of high-resolution multibeam data. Our preliminary results indicate that the shape of AHs could potentially be utilized to constrain the seafloor spreading evolution of regions devoid of magnetic anomalies and sediments (e.g., the North Pacific Cretaceous quiet zone).