Asymmetric dynamical behavior of thermochemical plumes and implications for Hawaiian lava composition

Simple item page
dc.contributor.authorBallmer, Maxim D.
dc.contributor.authorIto, Garrett
dc.contributor.authorCheng, Cheng
dc.date.accessioned2016-06-02T23:18:51Z
dc.date.available2016-06-02T23:18:51Z
dc.date.issued2015-02
dc.description.abstractThe Hawaiian Kea and Loa volcano trends have commonly been interpreted as directly reflecting a compositional zonation within the Hawaiian plume stem, inherited from the lowermost mantle. As this zonation is often associated with variations in mafic material, and as such materials, especially eclogites, impact mantle flow, this study aims to characterize the ascent and melting of bilaterally-zoned thermochemical plumes. Our geodynamic models predict that plumes bearing ≿12% eclogite tend to stagnate as a deep eclogitic pool (DEP) in the mid upper mantle where phase changes lead to a maximum in eclogite excess density. This behavior can explain recent seismic-tomography results, and predicts thermal asymmetry of material rising out of the DEP to feed the hotspot. Thermal asymmetry is caused by the effects of ambient-mantle flow or plume-stem zonation on DEP dynamics, and ultimately boosts peridotite melting on the melting zone’s hotter side. This hotter side is hence less dominated by melting of mafic materials, despite being fed by equally or more such materials than the cooler side. These results suggest that the Kea side of the Hawaiian Plume is equally or more eclogitic than the Loa side, opposite to previous interpretations. Care should thus be taken in mapping geographical variations in lava chemistry into the deep mantle.
dc.format.extent39
dc.identifier.citationBallmer, M. D., Ito, G. and Cheng, C. (2015) Asymmetric Dynamical Behavior of Thermochemical Plumes and Implications for Hawaiian Lava Composition, in Hawaiian Volcanoes: From Source to Surface (eds R. Carey, V. Cayol, M. Poland and D. Weis), John Wiley & Sons, Inc, Hoboken, NJ.
dc.identifier.doi10.1002/9781118872079.ch3
dc.identifier.urihttp://hdl.handle.net/10125/41039
dc.language.isoen-US
dc.publisherJohn Wiley & Sons, Inc.
dc.relation.ispartofseriesHawaiian Volcanoes: From Source to Surface;Chapter 3
dc.relation.urihttp://onlinelibrary.wiley.com/doi/10.1002/9781118872079.ch3/summary
dc.rightsCopyright © 2015 American Geophysical Union.
dc.subjectasymmetric thermochemical plumes
dc.subjectdeep eclogitic pool (DEP)
dc.subjectgeodynamic models
dc.subjectHawaiian Kea
dc.subjectHawaiian Loa
dc.subjectmafic materials
dc.subjectmantle flow
dc.subjectperidotite melting
dc.subjectseismic-tomography
dc.titleAsymmetric dynamical behavior of thermochemical plumes and implications for Hawaiian lava composition
dc.typeBook Chapter
dc.type.dcmiText

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Ballmer_et_al__AGU_Monograph_2014_in_press.pdf
Size:
15.04 MB
Format:
Adobe Portable Document Format
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.62 KB
Format:
Item-specific license agreed upon to submission
Description:
Download

Collections

SOEST Faculty & Researcher Works