Edge-driven microplate kinematics

Journal of Geophysical Research B: Solid Earth
By: , and 

Links

Abstract

It is known from plate tectonic reconstructions that oceanic microplates undergo rapid rotation about a vertical axis and that the instantaneous rotation axes describing the microplate's motion relative to the bounding major plates are frequently located close to its margins with those plates, close to the tips of propagating rifts. We propose a class of edge-driven block models to illustrate how slip across the microplate margins, block rotation, and propagation of rifting may be related to the relative motion of the plates on either side. An important feature of these edge-driven models is that the instantaneous rotation axes are always located on the margins between block and two bounding plates. According to those models the pseudofaults or traces of disrupted seafloor resulting from the propagation of rifting between microplate and major plates may be used independently to approximately trace the continuous kinematic evolution of the microplate back in time. Pseudofault geometries and matching rotations of the Easter microplate show that for most of its 5 m.y. history, block rotation could be driven by the drag of the Nazca and Pacific plates on the microplate's edges rather than by a shear flow of mantle underneath.

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Edge-driven microplate kinematics
Series title Journal of Geophysical Research B: Solid Earth
DOI 10.1029/92JB02749
Volume 98
Issue B4
Year Published 1993
Language English
Publisher American Geophysical Union
Publisher location Richmond, VA
Contributing office(s) Woods Hole Coastal and Marine Science Center
Description 13 p.
First page 6689
Last page 6701
Online Only (Y/N) N
Additional Online Files (Y/N) N