1993 Articles

Wilkes transform system and "nannoplate"

Goff, John; Fornari, Daniel J.; Cochran, James R.; Keeley, Christopher; Malinverno, Alberto

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 ~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.