Skip to Main content Skip to Navigation
Journal articles

Compositional heterogeneity near the base of the mantle transition zone beneath Hawaii

Abstract : Global seismic discontinuities near 410 and 660 km depth in Earth's mantle are expressions of solid-state phase transitions. These transitions modulate thermal and material fluxes across the mantle and variations in their depth are often attributed to temperature anomalies. Here we use novel seismic array analysis of SS waves reflecting off the 410 and 660 below the Hawaiian hotspot. We find amplitude-distance trends in reflectivity that imply lateral variations in wavespeed and density contrasts across 660 for which thermodynamic modeling precludes a thermal origin. No such variations are found along the 410. The inferred 660 contrasts can be explained by mantle composition varying from average (pyrolitic) mantle beneath Hawaii to a mixture with more melt-depleted harzburgite southeast of the hotspot. Such compositional segregation was predicted, from petrological and numerical convection studies, to occur near hot deep mantle upwellings like the one often invoked to cause volcanic activity on Hawaii.
Document type :
Journal articles
Complete list of metadata

https://hal-insu.archives-ouvertes.fr/insu-03595920
Contributor : Nathalie POTHIER Connect in order to contact the contributor
Submitted on : Thursday, March 3, 2022 - 2:35:45 PM
Last modification on : Saturday, March 5, 2022 - 3:32:33 AM
Long-term archiving on: : Saturday, June 4, 2022 - 7:19:34 PM

File

s41467-018-03654-6.pdf
Publisher files allowed on an open archive

Licence


Distributed under a Creative Commons Attribution 4.0 International License

Identifiers

Collections

Citation

Chunquan Yu, Elizabeth A. Day, Maarten V. de Hoop, Michel Campillo, Saskia Goes, et al.. Compositional heterogeneity near the base of the mantle transition zone beneath Hawaii. Nature Communications, Nature Publishing Group, 2018, 9, p. 62-77. ⟨10.1038/s41467-018-03654-6⟩. ⟨insu-03595920⟩

Share

Metrics

Record views

12

Files downloads

2