Upper mantle P wave velocity structure and transition zone thickness beneath the Arabian Shield

Margaret H. Benoit, Andrew Arnold Nyblade, John C. VanDear, Harold Gurrola

Research output: Contribution to journalArticle

51 Citations (Scopus)

Abstract

We use P wave tomography and receiver function analysis to place new constraints on the nature of the thermal anomaly in the upper mantle beneath the Arabian Shield. A broad, low velocity anomaly is found in the upper mantle characterized by a strong lateral velocity gradient, with a peak to peak anomaly of at least 4-6% extending from the Red Sea eastward into the interior of the shield. The lowest velocities are found under the region adjacent to the Red Sea where elevations are more than 1 km higher than elsewhere in the Arabian Shield. We infer that large lateral temperature variations exist beneath the Arabian Shield associated with the higher elevations near the Red Sea. Receiver function stacks of P to S conversions from the 410 and 660 km discontinuities do not indicate thinning of the transition zone, suggesting that the broad, low velocity anomaly is likely confined to depths shallower than 410 km.

Original languageEnglish (US)
Pages (from-to)38-31
Number of pages8
JournalGeophysical Research Letters
Volume30
Issue number10
StatePublished - May 15 2003

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Red Sea
velocity structure
P waves
transition zone
P-wave
wave velocity
upper mantle
shield
Earth mantle
anomalies
low speed
anomaly
receivers
temperature anomaly
tomography
thinning
discontinuity
gradients
sea
temperature

All Science Journal Classification (ASJC) codes

  • Earth and Planetary Sciences (miscellaneous)

Cite this

Benoit, Margaret H. ; Nyblade, Andrew Arnold ; VanDear, John C. ; Gurrola, Harold. / Upper mantle P wave velocity structure and transition zone thickness beneath the Arabian Shield. In: Geophysical Research Letters. 2003 ; Vol. 30, No. 10. pp. 38-31.
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Upper mantle P wave velocity structure and transition zone thickness beneath the Arabian Shield. / Benoit, Margaret H.; Nyblade, Andrew Arnold; VanDear, John C.; Gurrola, Harold.

In: Geophysical Research Letters, Vol. 30, No. 10, 15.05.2003, p. 38-31.

Research output: Contribution to journalArticle

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