Impact of Spreading Rate and Age‐Offset on Oceanic Transform Fault Morphology
Oceanic transform faults (OTFs) are an inherent part of seafloor spreading and plate tectonics, whereas the process controlling their morphology remains enigmatic. Here, we systematically quantify variations in transform morphology and their dependence on spreading rate and age-offset, based on a compilation of shipborne bathymetric data from 94 OTFs at ultraslow- to intermediate-spreading ridges. In general, the length, width and depth of OTFs scale systematically better with age-offset rather than spreading rate. This observation supports recent geodynamic models proposing that cross-transform extension scaling with age-offset, is a key process of transform dynamics. On the global scale, OTFs with larger age-offsets tend to have longer, wider, and deeper valleys. However, at small age-offsets (<5 Myr), scatters in the depth and width of OTFs increase, indicating that small age-offset OTFs with weak lithospheric strength are easily affected by secondary tectonic processes.