New Aspects of Rotational Dynamics Within the North American-Pacific Ductile Shear Zone

  1. John W. Hillhouse
  1. Erik R. Ivins

Published Online: 18 MAR 2013

DOI: 10.1029/GM050p0179

Deep Structure and Past Kinematics of Accreted Terranes

Deep Structure and Past Kinematics of Accreted Terranes

How to Cite

Ivins, E. R. (1989) New Aspects of Rotational Dynamics Within the North American-Pacific Ductile Shear Zone, in Deep Structure and Past Kinematics of Accreted Terranes (ed J. W. Hillhouse), American Geophysical Union, Washington, D. C.. doi: 10.1029/GM050p0179

Author Information

  1. Earth and Planetary Physics Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena

Publication History

  1. Published Online: 18 MAR 2013
  2. Published Print: 1 JAN 1989

ISBN Information

Print ISBN: 9780875904542

Online ISBN: 9781118666609

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Keywords:

  • Geology, Structural—Congresses;
  • Geodynamics—Congresses;
  • Earth—Crust—Congresses

Summary

A positive seismic P-wave anomaly exists beneath the Transverse Ranges, California down to depths of about 250 km [Humphreys et al., 1984]. The geometry of oblique convergence is suggested by the spatial distribution of the anomaly; indicating that a cold lithospheric fragment has descended into the mantle during the Plio-Pleistocene (0– 5Ma). The P-wave anomaly maintains a local viscosity so high that the structure may be considered to be effectively rigid on the 10 Ma time scale. The mode of North American-Pacific interplate deformation between Mendicino and Rivera triple junctions consists of right lateral shearing motion. The theory of two-phase flow dynamics is used to examine the horizontal movements of the anomaly. The local perturbations to this large scale shearing flow are highly rotational.