Results 41 to 50 of about 9,129 (164)

Effects of Heat‐Producing Elements on the Stability of Deep Mantle Thermochemical Piles

Geochemistry, Geophysics, Geosystems, 2020
Geochemical observations of ocean island and mid‐ocean ridge basalts suggest that abundances of heat‐producing elements (HPEs: U, Th, and K) vary within the mantle.
Robert I. Citron, Diogo L. Lourenço, Alfred J. Wilson, Antoniette G. Grima, Scott A. Wipperfurth, Maxwell L. Rudolph, Sanne Cottaar, Laurent G. J. Montési   +7 more
doaj   +1 more source

Rethinking the chemical heterogeneity of the mantle

Eos, Transactions American Geophysical Union, 1997
Mantle‐derived magmas are among the best sources of information about the chemistry of the Earth's mantle. For the past two decades, geochemists have used ratios of certain trace elements and isotopes of these magmas, considered to be largely unaffected by crystal‐liquid separation, to argue that the mantle is compositionally heterogeneous.
Wendy A. Bohrson, Jon P. Davidson, John A. Wolff   +2 more
openaire   +1 more source

Seamounts in the Subduction Factory [PDF]

Oceanography, 2010
The “Subduction Factory” is a metaphor for the geochemical processing of subducted oceanic crust and sediment into components that are either incorporated into the volcanic arc or recycled into Earth’s mantle.
Hubert Staudigel, Anthony A.P. Koppers, Terry A. Plank, Barry B. Hanan   +3 more
doaj  

Ancient recycled lower crust in the mantle source of recent Italian magmatism

Nature Communications, 2019
Recycling of Earth’s crust through subduction and delamination contributes to mantle heterogeneity. Here, the authors measure coupled Sr-Nd-Pb isotope compositions of melt inclusions in Italian potassium-rich lavas, they suggest their results indicate a ...
Janne M. Koornneef, Igor Nikogosian, Manfred J. van Bergen, Pieter Z. Vroon, Gareth R. Davies   +4 more
doaj   +1 more source

Density structure of Earth’s lowermost mantle from Stoneley mode splitting observations

Nature Communications, 2017
Large-low-shear-wave velocity provinces (LLSVPs) are present at the core–mantle boundary. Here, the authors show that splitting of Stoneley modes is probably due to a lower density of LLSVPs than the surrounding mantle because of the presence of post ...
Paula Koelemeijer, Arwen Deuss, Jeroen Ritsema   +2 more
doaj   +1 more source

Heterogeneity in mantle carbon content from CO2-undersaturated basalts

Nature Communications, 2017
Melting dynamics are affected by the amount of carbon in the Earth’s mantle. Le Voyeret al. report undegassed carbon concentrations from olivine-hosted melt inclusions from the Mid-Atlantic Ridge finding that carbon content varies by two orders of ...
M. Le Voyer, K.A. Kelley, E. Cottrell, E.H. Hauri   +3 more
doaj   +1 more source

Combined Lithophile‐Siderophile Isotopic Constraints on Hadean Processes Preserved in Ocean Island Basalt Sources

Geochemistry, Geophysics, Geosystems, 2021
Detection of Hadean isotopic signatures within modern ocean island basalts (OIB) has greatly influenced understanding of Earth's earliest history and long‐term dynamics.
Bradley J. Peters, Andrea Mundl‐Petermeier, Richard W. Carlson, Richard J. Walker, James M. D. Day   +4 more
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Volatile Element Evidence of Local MORB Mantle Heterogeneity Beneath the Southwest Indian Ridge, 48°–51°E

Geochemistry, Geophysics, Geosystems, 2021
The mantle source beneath the Southwest Indian Ridge (SWIR) reflects a complex history of contamination. Magmatic volatile contents are vital tracers of these kinds of heterogeneities, which may fractionate otherwise constant volatile/non‐volatile ...
Wei Wang, Katherine A. Kelley, Zhenggang Li, Fengyou Chu, Yunpeng Dong, Ling Chen, Yanhui Dong, Jie Li   +7 more
doaj   +1 more source

Light oxygen isotopic composition in deep mantle reveals oceanic crust subduction before 3.3 billion years ago

Communications Earth & Environment
Compositional heterogeneity exists in Earth’s deep mantle, which can be caused by the subduction of oceanic slabs. How early this process started on Earth remains highly debated due to the scarcity of early Archean materials with pristine mantle ...
Dongjian Ouyang, Huiming Bao, Gary R. Byerly, Qiuli Li   +3 more
doaj   +1 more source

Seismological Evidence for Heterogeneity of the Mantle

Journal of geomagnetism and geoelectricity, 1970
The latest results concerning the depth variation of Q, P- and S-wave velocities obtained by various seismological methods are reviewed with special emphasis on the regional variation. The body-wave travel time and the slope, dT/dΔ, have been inverted to obtain P- and S-wave velocity distributions within the mantle. The P velocity is now believed to be
openaire   +3 more sources