A sharp lithosphere-asthenosphere boundary imaged beneath eastern North America
Article Abstract:
Converted seismic phases in eastern North America are used to image a very sharp seismic velocity gradient at the base of the lithosphere that is a 3-11 per cent drop in shear-wave velocity over a depth range of 11 km or less at 90-110 km depth. A strong, sharp boundary cannot be reconciled with a purely thermal gradient of the given magnitude but could not be explained by an aethenosphere that contains a few percent partial melt or that is enriched in volatiles relative to the lithosphere.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2005
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Arc-parallel flow in the mantle wedge beneath Costa Rica and Nicaragua
Article Abstract:
The isotope geochemistry and seismic velocity anisotropic studies are employed to explain the arc-parallel flow in the mantle wedge beneath Costa Rica and Nicaragua. The isotopic signature of the flow is shown to continuously decrease from the central Costa Rica to the northwestern Nicaragua.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2008
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Boundary-layer mantle flow under the Dead Sea transform fault inferrred from seismic anisotrophy
Article Abstract:
The lithosphere is expected to retain its original crystallographic fabric frozen in during previous tectonic events. The olivine crystallographic a-axis aligns subparallel to the strike of transform-type plate boundaries.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2003
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