Foundering lithosphere imaged beneath the southern Sierra Nevada, California, USA.
Seismic tomography reveals garnet-rich crust and mantle lithosphere descending into the upper mantle beneath the southeastern Sierra Nevada. The descending lithosphere consists of two layers: an iron-rich eclogite above a magnesium-rich garnet peridotite. These results place descending eclogite above and east of high P wave speed material previously imaged beneath the southern Great Valley, suggesting a previously unsuspected coherence in the lithospheric removal process.
Department of Geological Sciences, University of Colorado at Boulder, 2200 Colorado Avenue, Boulder, CO 80309-0399, USA. oliver.boyd@colorado.edu
Oliver S
OS
Boyd
Craig H
CH
Jones
Anne F
AF
Sheehan