Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published 1998 | public
Book Section - Chapter

Cenozoic Tectonism in the Central Basin and Range: Motion of the Sierran-Great Valley Block

Abstract

According to geologic reconstructions, the motion of the Sierran-Great Valley block with respect to the Colorado Plateau was mainly westerly at more than 20 mm/yr from 16 to 10 Ma, changing to northwest or NNW since 8 to 10 Ma, at an average rate of 15 mm/yr. These kinematics are consistent with two other independent methods of determining the position of the block since 20 Ma-reconstructions based on paleomagnetic data from range blocks that bound the Basin and Range on the west, and a revised history of Pacific-North America plate motion based on a global plate circuit (Atwater and Stock, 1998, this issue). The plate-tectonic reconstruction shows a change to more northerly motion between the Pacific and North American plates at ~8 Ma, in concert with the motion of the Sierran-Great Valley block. Moreover, the northeast limit of extant oceanic crust (as indicated by the reconstruction of the continental geology) tracks closely with the southwest limit of extant continental crust (as indicated by the positions of oceanic plates) since 20 Ma. The coordination between plate motions and the intraplate geology suggests that plate-boundary forces strongly influenced deformation within the continent.

Additional Information

© 1998 Bellwether Publishing.

Additional details

Created:
August 22, 2023
Modified:
October 26, 2023