Double seismic discontinuities at the base of the mantle transition zone near the Mariana slab

Details Double seismic discontinuities at the base of the mantle transition zone near the Mariana slab Double seismic discontinuities at the base of the mantle transition zone near the Mariana slab

Aug 2007

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007georl..3416316t&link_type=abstract

Geophysical Research Letters, Volume 34, Issue 16, CiteID L16316

Physics

4

Seismology: Mantle (1212, 1213, 8124), Seismology: Subduction Zones (1207, 1219, 1240), Seismology: Body Waves, Mineralogy And Petrology: Subduction Zone Processes (1031, 3060, 8170, 8413), Geographic Location: Pacific Ocean

Scientific paper

We use P-to-S converted phases from teleseimic data recorded at island and ocean bottom stations in Mariana to investigate the upper mantle structure in the region. We find evidence for double seismic discontinuities at the base of the transition zone near the Mariana slab. A shallower discontinuity is imaged at depths of ~650-715 km and a deeper interface lies at ~740-770 km depth. The large lateral extent at near constant depths for both features is consistent with horizontal interfaces rather than small-scale scatterers. The amplitude ratios of the seismic signals suggest that the shear velocity contrast across the two interfaces is comparable. These characteristics support the notion that the discontinuities are the results of phase transformations in olivine (ringwoodite to post-spinel) and non-olivine component (ilminite to perovskite), respectively, for the pyrolite model of mantle composition.

Affiliated with

Also associated with

No associations

Rating

Double seismic discontinuities at the base of the mantle transition zone near the Mariana slab does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Double seismic discontinuities at the base of the mantle transition zone near the Mariana slab, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Double seismic discontinuities at the base of the mantle transition zone near the Mariana slab will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-974025