Papers on Seismology
Tomographic image of the southern California mantle
Article first published online: 20 SEP 2012
Copyright 1990 by the American Geophysical Union.
Journal of Geophysical Research: Solid Earth (1978–2012)
Volume 95, Issue B12, pages 19725–19746, 10 November 1990
How to Cite
1990), Tomographic image of the southern California mantle, J. Geophys. Res., 95(B12), 19725–19746, doi:10.1029/JB095iB12p19725., and (
- Issue published online: 20 SEP 2012
- Article first published online: 20 SEP 2012
- Manuscript Accepted: 13 JUN 1990
- Manuscript Received: 10 NOV 1987
P wave teleseismic travel time delays recorded by the Southern California Array are inverted by the method of backprojection tomography to obtain images of variations in the P wave velocity structure to a depth of 750 km. Two major upper mantle features arc resolved: one beneath the Transverse Ranges region and another beneath the Salton Trough region. The Transverse Ranges feature appears as a curtainlike, east trending, high-velocity anomaly. This feature is ∼60 km thick, extends most deeply on its eastern end (to ∼250 km), and attains a maximum velocity −3% greater than average southern California mantle of the same depth. The Salton Trough feature, which is not as well resolved as the Transverse Ranges feature, is composed of low velocities in the upper 70–100 km. These P wave velocities arc depressed 3–4% compared to average southern California mantle. Tests of the inversion indicate the major aspects of the imaged structure are authentic.