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Title: Confirming a pyrolitic lower mantle using self-consistent pressure scales and new constraints on CaSiO 3 perovskite: A Pyrolitic Lower Mantle

Authors:
 [1];  [2];  [1];  [3];  [4];  [5]
  1. Laboratory of Seismology and Physics of Earth's Interior, School of Earth and Planetary Sciences, University of Science and Technology of China, Hefei China
  2. Laboratory of Seismology and Physics of Earth's Interior, School of Earth and Planetary Sciences, University of Science and Technology of China, Hefei China; National Geophysics Observatory, Mengcheng China
  3. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan China
  4. Center for Advanced Radiation Sources, University of Chicago, Chicago Illinois USA
  5. Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin Texas USA; Center for High Pressure Science and Technology Advanced Research, Shanghai China
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
NSFFOREIGN
OSTI Identifier:
1329403
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Geophysical Research. Solid Earth; Journal Volume: 121; Journal Issue: 7
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Sun, Ningyu, Mao, Zhu, Yan, Shuai, Wu, Xiang, Prakapenka, Vitali B., and Lin, Jung-Fu. Confirming a pyrolitic lower mantle using self-consistent pressure scales and new constraints on CaSiO 3 perovskite: A Pyrolitic Lower Mantle. United States: N. p., 2016. Web. doi:10.1002/2016JB013062.
Sun, Ningyu, Mao, Zhu, Yan, Shuai, Wu, Xiang, Prakapenka, Vitali B., & Lin, Jung-Fu. Confirming a pyrolitic lower mantle using self-consistent pressure scales and new constraints on CaSiO 3 perovskite: A Pyrolitic Lower Mantle. United States. doi:10.1002/2016JB013062.
Sun, Ningyu, Mao, Zhu, Yan, Shuai, Wu, Xiang, Prakapenka, Vitali B., and Lin, Jung-Fu. 2016. "Confirming a pyrolitic lower mantle using self-consistent pressure scales and new constraints on CaSiO 3 perovskite: A Pyrolitic Lower Mantle". United States. doi:10.1002/2016JB013062.
@article{osti_1329403,
title = {Confirming a pyrolitic lower mantle using self-consistent pressure scales and new constraints on CaSiO 3 perovskite: A Pyrolitic Lower Mantle},
author = {Sun, Ningyu and Mao, Zhu and Yan, Shuai and Wu, Xiang and Prakapenka, Vitali B. and Lin, Jung-Fu},
abstractNote = {},
doi = {10.1002/2016JB013062},
journal = {Journal of Geophysical Research. Solid Earth},
number = 7,
volume = 121,
place = {United States},
year = 2016,
month = 7
}
  • The relative changes between shear and compressional velocities (R{sub SP} = {partial_derivative} ln V{sub S}/{partial_derivative} ln V{sub P}), bulk sound and shear velocities (R{sub CS} = {partial_derivative} ln V{sub C}/{partial_derivative} ln V{sub S}), and density versus shear wave velocity (R{sub {rho}S} = {partial_derivative} ln {rho}/{partial_derivative} ln V{sub S}) in response to thermal and chemical variations were investigated for the pyrolitic lower mantle. For heterogeneities with thermal origins, R{sub SP} increases from 1.7 to 2.0 together with R{sub {rho}S} decreasing from 0.4 to 0.2 and R{sub CS} = 0.27 from the top to the bottom of the lower mantle. In comparison,more » chemical variations (bulk iron or silica contents) are characterized by R{sub SP} < 1.5 and R{sub CS} > 0.5 at lower mantle depths. Negative values of R{sub {rho}S} and R{sub CS} are indicative of chemical anomalies in the lower mantle, but a combination of thermal and chemical heterogeneities may be required to produce velocity and density anomalies at the magnitudes observed in seismic data. Further refinement of these characteristics requires data on the higher order pressure and temperature derivatives of the elastic moduli of the constituent phases.« less
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