English
 
Privacy Policy Disclaimer
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
Add to Basket
  Local TagsRelease HistoryDetailsSummary

Released
Journal Article

Seismic evidence for an Iceland thermo-chemical plume in the Earth's lowermost mantle

Authors

He,  Yumei
External Organizations;
GEOFON, Deutsches GeoForschungsZentrum;

Wen,  Lianxing
External Organizations;
GEOFON, Deutsches GeoForschungsZentrum;

Capdeville,  Yann
External Organizations;
GEOFON, Deutsches GeoForschungsZentrum;

Zhao,  Liang
External Organizations;
GEOFON, Deutsches GeoForschungsZentrum;

External Ressource
No external resources are shared
Fulltext (public)
There are no public fulltexts stored in GFZpublic
Supplementary Material (public)
There is no public supplementary material available
Citation

He, Y., Wen, L., Capdeville, Y., Zhao, L. (2015): Seismic evidence for an Iceland thermo-chemical plume in the Earth's lowermost mantle. - Earth and Planetary Science Letters, 417, 19-27.
https://doi.org/10.1016/j.epsl.2015.02.028


Cite as: https://gfzpublic.gfz-potsdam.de/pubman/item/item_3169924
Abstract
We constrain the geographic extent, geometry and velocity structure of the seismic anomaly near the Earth's core–mantle boundary (CMB) beneath Iceland, based on travel time and three-dimensional waveform modeling of the seismic data sampling the lowermost mantle beneath Iceland. Our analysis suggests a mushroom-shaped low velocity anomaly situated in the lowermost mantle beneath Iceland surrounded by a high velocity province. The best fitting mushroom-shaped model is 600 km high and has a stem with a radius of 350 km in the lowermost 250 km of the mantle and a cap with increasing radii from 550 km at 250 km above the CMB to 650 km at 600 km above the CMB. The shear velocity structure varies from 0% at the top to -3% at 250 km above the CMB and to -6% at the CMB. These inferred seismic features, in combination with the previous evidence of existence of ultra-low velocity zones at the base of the mantle beneath the region, suggest that Iceland represents a thermo-chemical plume generated by interaction of downwelling and a localized chemical anomaly at the base of the mantle.