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 a pproximately 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 ''n annoplate'' to distinguish it both as a separate small area of lithosp here between the Pacific and Nazca plates and as a smaller and less st able phenomenon than a microplate.