Seismic detection of folded, subducted lithosphere at the core–mantle boundary

  title={Seismic detection of folded, subducted lithosphere at the core–mantle boundary},
  author={Alexander R. Hutko and Thorne Lay and Edward J. Garnero and Justin S. Revenaugh},
Seismic tomography has been used to infer that some descending slabs of oceanic lithosphere plunge deep into the Earth's lower mantle. The fate of these slabs has remained unresolved, but it has been postulated that their ultimate destination is the lowermost few hundred kilometres of the mantle, known as the D″ region. Relatively cold slab material may account for high seismic velocities imaged in D″ beneath areas of long-lived plate subduction, and for reflections from a seismic velocity… Expand
Seismic evidence for a sharp lithospheric base persisting to the lowermost mantle beneath the Caribbean
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Multiple seismic reflectors in Earth’s lowermost mantle
The results imply that the lowermost mantle is more complex than hitherto thought and that interfaces and compositional heterogeneity occur beyond the D″ region sensu stricto. Expand
Atlas of the underworld : Slab remnants in the mantle, their sinking history, and a new outlook on lower mantle viscosity
Abstract Across the entire mantle we interpret 94 positive seismic wave-speed anomalies as subducted lithosphere and associate these slabs with their geological record. We document this as the AtlasExpand
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The Earth’s mantle is chemically and thermally heterogeneous varying in 3-dimensions and on many length-scales. Subduction introduces slabs into the mantle while interactions with the core may enrichExpand
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Seismic evidence for the depression of the D ″ discontinuity beneath the Caribbean: Implication for slab heating from the Earth's core
The lowermost 100–300 km of the Earth's mantle commonly regarded as the thermal boundary layer (TBL) of mantle circulation is characterized by its complex physical properties. Beneath the CaribbeanExpand
Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion
Waveform inversion is conducted using a data set of ~7700 transverse component records to infer the detailed three-dimensional S-velocity structure in the lowermost 400 km of the mantle in the study region so that it can investigate how cold paleoslabs interact with the hot TBL above the core-mantle boundary (CMB). Expand
Lower mantle scattering profiles and fabric below Pacific subduction zones
Abstract The Earth's mantle is compositionally evolving principally through the process of mid-ocean ridge basalt production (95% by lithospheric area, but also by way of arc magmatism (> 5%) andExpand
Seismic imaging the D? region beneath the Central Atlantic
Abstract The lowermost mantle beneath the central Atlantic is bounded by the western edge of African Large Low Shear Wave Province (LLSVP) and a high-velocity region beneath the eastern Americas,Expand
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Images of the scattering field near the core–mantle boundary (CMB) beneath the Caribbean were obtained from migration processing of PKIKP precursors recorded by a broadband seismic array in theExpand


High-resolution imaging of lowermost mantle structure under the Cocos plate
[1] Broadband seismic shear waves are analyzed to investigate the fine-velocity structure in the lowermost mantle beneath the Cocos plate, a region where previous studies have indicated the presenceExpand
Slabs in the lower mantle and their modulation of plume formation
Numerical mantle convection models indicate that subducting slabs can reach the core-mantle boundary (CMB) for a wide range of assumed material properties and plate tectonic histories. An increase inExpand
Mantle shear–wave tomography and the fate of subducted slabs
  • S. Grand
  • Geology, Medicine
  • Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences
  • 2002
A new seismic model of the three–dimensional variation in shear velocity throughout the Earth's mantle is presented, derived entirely from shear bodywave travel times and compared with other global shear models. Expand
Seismic heterogeneous structure in the lowermost mantle beneath the southwestern Pacific
[1] The P and S wave velocity structure of the D″ layer beneath the southwestern Pacific was investigated by using short-period data from 12 deep events in the Tonga-Fiji region recorded by theExpand
A lower mantle S-wave triplication and the shear velocity structure of D"
Summary. A lower mantle S-wave triplication detected with short- and longperiod WWSSN and CSN recordings indicates a substantial shear velocity discontinuity near 280 km above the core-mantleExpand
Finite frequency tomography of D″ shear velocity heterogeneity beneath the Caribbean
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High‐resolution investigation of shear wave anisotropy in D″ beneath the Cocos Plate
[1] Broadband shear wave signals from 16 deep South American earthquakes are used in a high-resolution analysis of lowermost mantle structure beneath the Cocos Plate. Shear wave splitting of 162 ScSExpand
Short‐period P wave constraints on D″ reflectivity
We present evidence of a P wave reflector in D beneath the central and eastern equatorial Pacific obtained from nearly 7000 short-period seismic recordings of earthquakes in the Tonga-Fiji and SouthExpand
Global seismic tomography: A snapshot of convection in the Earth: GSA Today
Two new global high-resolution models of the P-wave and S-wave seismic structure of the mantle were derived independently using different inversion techniques and different data sets, but they showExpand
Seismic imaging of structural heterogeneity in Earth's mantle: evidence for large-scale mantle flow.
This model is based on seismic wave travel times and wave shapes from over 100,000 ground motion recordings of earthquakes that occurred between 1980 and 1998 and shows signatures of plate tectonic processes to a depth of about 1,200 km in the mantle. Expand