Geoscience Reference
In-Depth Information
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10.7 Concluding Remarks
Significant progress has been made in linking
seismic observations of mantle discontinuities
with mineralogical phase transitions or rheologi-
cal boundaries. The transition zone discontinu-
ities are relatively well understood, with the
combined influence of phase transitions in the
olivine and garnet systems. However, directly
interpreting the observations in terms of temper-
ature and compositional variations is less suc-
cessful, especially as there are strong variations
between what is observed with different seismic
data types and the mineralogical data has large
uncertainties. More progress is needed in recon-
ciling observations using different data types. In
addition, several reflectors have been observed in
the upper and lower mantle. More constraints
are required from mineral physics and seismol-
ogy to determine the regional variation of these
additional reflectors and find mineralogical or
rheological explanations.
Acknowledgements
The research was funded by the European
Research Council under the European Com-
munitys Seventh Framework Programme (FP7/
2007-2013)/ERC grant agreement number
204995. Jennifer Andrews and Elizabeth Day
were funded by NERC PhD studentships.
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