Lateral variation of upper mantle structure beneath New Caledonia determined from P-wave receiver function: evidence for a fossil subduction zone

seismic study of upper mantle beneath the nw iran using p receiver function

rf method is now a well-known tool for studying crustal and upper mantle structure when such a complete data set is available. we compute p receiver functions to investigate the upper mantle discontinuity beneath the northwest of iran. we selected data from teleseismic events (mb ? 5.5, 30 ?>? > 95?) recorded from 1995 to 2008 at 8 three component short period stations from tabriz telemetry sei...

Petrological Evolution of the Upper Mantle Beneath the Southern Sanandaj-Sirjan Zone: Evidence from Kuhshah Peridotite Massif, Southeast Iran

The Kuhshah ultramafic complex is located in the south-east of Sanandaj-Sirjan metamorphic zone, near the probable remnants of Neotethys plate in Iran. It consists of highly depleted harzburgites, dunites, chromitite bands and altered gabbros. The ultramafic parts have been intruded by numerous clinopyroxenite dykes and veins. In the harzburgites, there are different generations of olivine, ort...

Evidence for a chemical-thermal structure at base of mantle from sharp lateral P-wave variations beneath Central America.

Compressional waves that sample the lowermost mantle west of Central America show a rapid change in travel times of up to 4 s over a sampling distance of 300 km and a change in waveforms. The differential travel times of the PKP waves (which traverse Earth's core) correlate remarkably well with predictions for S-wave tomography. Our modeling suggests a sharp transition in the lowermost mantle f...

Upper mantle Q and thermal structure beneath Tanzania, East Africa from teleseismic P wave spectra

[1] We measure P wave spectral amplitude ratios from deep-focus earthquakes recorded at broadband seismic stations of the Tanzania network to estimate regional variation of sublithospheric mantle attenuation beneath the Tanzania craton and the eastern branch of the East African Rift. One-dimensional profiles of QP adequately explain the systematic variation of P wave attenuation in the sublitho...

Mapping the mantle transition zone beneath Hawaii from Ps receiver functions: Evidence for a hot plume and cold mantle downwellings