Bulk Attenuation in the Earth’s Mantle Due to Phase Transitions
The calculated bulk attenuation due to phase transition from mineral physics data is reported here. With relaxation time less than 1 s, the calculated value for a pyrolite mantle is consistent with the inverted bulk attenuation of the upper mantle from seismic observations. The two important mechanisms of phase transitions, diffusion-controlled and kinetics-controlled, have different relaxation time as indicated by the models here. The diffusion controlled is more likely to contribute to the observed seismic bulk attenuation than the kinetic-controlled process based on the available diffusivity and kinetics data. The correlation between the bulk attenuation and relaxation time emphasizes the importance of a number of parameters in the mineral physics database such as Fe-Mg diffusivity and kinetics in olivine-wadsleyite-ringwoodite-perovskite, Mg-Ca-Al-Si diffusivity and kinetics in pyroxene-garnet-Ca perovskite, some of which are still unknown.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States)
- Sponsoring Organization:
- USDOE SC OFFICE OF SCIENCE (SC)
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 1042059
- Report Number(s):
- BNL-97737-2012-JA; PEPIAM; TRN: US201212%%470
- Journal Information:
- Physics of the Earth and Planetary Interiors, Vol. 183, Issue 3-4; ISSN 0031-9201
- Country of Publication:
- United States
- Language:
- English
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