Wilkes Transform System and Nannoplate

A recent Hydrosweep survey of the Wilkes transform system, the second-fastest-slipping transform on the mid-ocean ridge system, shows it to be a highly complex and continually evolving plate boundary. An area approximately 50 km2 north of the eastern part of the Wilkes transform appears to be rotating counterclockwise in accordance with the theory of edge-driven microplate kinematics. We have called this region a ''nannoplate'' to distinguish it both as a separate small area of lithosphere between the Pacific and Nazca plates and as a smaller and less stable phenomenon than a microplate.