start-ver=1.4
cd-journal=joma
no-vol=60
cd-vols=
no-issue=8
article-no=
start-page=1681
end-page=1715
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2019
dt-pub=20190912
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Transition from Plume-driven to Plate-driven Magmatism in the Evolution of the Main Ethiopian Rift
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract= New K-Ar ages, major and trace element concentrations, and Sr-Nd-Pb isotope data are presented for Oligocene to recent mafic volcanic rocks from the Ethiopian Plateau, the Main Ethiopian Rift (MER), and the Afar depression. Chronological and geochemical data from this study are combined with previously published datasets to reveal secular variations in magmatism throughout the entire Ethiopian volcanic region. The mafic lavas in these regions show variability in terms of silica-saturation (i.e. alkaline and sub-alkaline series) and extent of differentiation (mafic through intermediate to felsic). The P-T conditions of melting, estimated using the least differentiated basalts, reveal a secular decrease in the mantle potential temperature, from when the flood basalt magmas erupted (up to 1600 degrees C) to the time of the rift-related magmatism (<1500 degrees C). Variations in the Sr-Nd-Pb isotopic compositions of the mafic lavas can account for the involvement of multiple end-member components. The relative contributions of these end-member components vary in space and time owing to changes in the thermal condition of the asthenosphere and the thickness of the lithosphere. The evolution of the Ethiopian rift is caused by a transition from plume-driven to plate-driven mantle upwelling, although the present-day mantle beneath the MER and the Afar depression is still warmer than normal asthenosphere.
en-copyright=
kn-copyright=

en-aut-name=FeyissaDejene Hailemariam
en-aut-sei=Feyissa
en-aut-mei=Dejene Hailemariam
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=KitagawaHiroshi
en-aut-sei=Kitagawa
en-aut-mei=Hiroshi
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=BizunehTesfaye Demissie
en-aut-sei=Bizuneh
en-aut-mei=Tesfaye Demissie
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=TanakaRyoji
en-aut-sei=Tanaka
en-aut-mei=Ryoji
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=KabetoKurkura
en-aut-sei=Kabeto
en-aut-mei=Kurkura
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

en-aut-name=NakamuraEizo
en-aut-sei=Nakamura
en-aut-mei=Eizo
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=6
ORCID=

affil-num=1
en-affil=The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University
kn-affil=

affil-num=2
en-affil=The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University
kn-affil=

affil-num=3
en-affil=The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University
kn-affil=

affil-num=4
en-affil=The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University
kn-affil=

affil-num=5
en-affil=The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University
kn-affil=

affil-num=6
en-affil=The Pheasant Memorial Laboratory for Geochemistry and Cosmochemistry, Institute for Planetary Materials, Okayama University
kn-affil=
en-keyword=Ethiopian Plateau
kn-keyword=Ethiopian Plateau
en-keyword=Ethiopian rift
kn-keyword=Ethiopian rift
en-keyword=Afar depression
kn-keyword=Afar depression
en-keyword=mantle source
kn-keyword=mantle source
en-keyword=mantle melting
kn-keyword=mantle melting
END