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Temperature profile in the lowermost mantle from seismological and mineral physics joint modeling.

ABSTRACT: The internal structure of the core-mantle boundary (CMB) region of the Earth plays a crucial role in controlling the dynamics and evolution of our planet. We have developed a comprehensive model based on the radial variations of shear velocity in the D'' layer (the base of the lower mantle) and the high-P,T elastic properties of major candidate minerals, including the effects of post-perovskite phase changes. This modeling shows a temperature profile in the lowermost mantle with a CMB temperature of 3,800 +/- 200 K, which suggests that lateral temperature variations of 200-300 K can explain much of the large velocity heterogeneity observed in D''. A single-crossing phase transition model was found to be more favorable in reproducing the observed seismic wave velocity structure than a double-crossing phase transition model.

SUBMITTER: Kawai K

PROVIDER: S-EPMC2799726 | biostudies-literature | 2009 Dec

REPOSITORIES: biostudies-literature

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Temperature profile in the lowermost mantle from seismological and mineral physics joint modeling.

Kawai Kenji K Tsuchiya Taku T

Proceedings of the National Academy of Sciences of the United States of America 20091211 52

The internal structure of the core-mantle boundary (CMB) region of the Earth plays a crucial role in controlling the dynamics and evolution of our planet. We have developed a comprehensive model based on the radial variations of shear velocity in the D'' layer (the base of the lower mantle) and the high-P,T elastic properties of major candidate minerals, including the effects of post-perovskite phase changes. This modeling shows a temperature profile in the lowermost mantle with a CMB temperatur ...[more]

PMID: 20018735

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