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Earth's core is essentially composed of a light-element bearing iron-nickel alloy (Birch 1964). The nickel content in the core has negligible effects on physical properties such as density and compressibility (e.g., Lin et al. 2003; Kantor et al. 2007; Mar ...
Planetesimal were the first planetary objects to form in the solar system, which later grew to make the proto-planets. Most of these bodies were differentiated as a result of internal heating. Several differentiated bodies have, then, been accreted followi ...
Recent palaeomagnetic observations(1) report the existence of a magnetic field on Earth that is at least 3.45 billion years old. Compositional buoyancy caused by inner-core growth(2) is the primary driver of Earth's present-day geodynamo(3-5), but the inne ...
The formation of Earth's core left behind geophysical and geochemical signatures in both the core and mantle that remain to this day. Seismology requires that the core be lighter than pure iron and therefore must contain light elements, and the geochemistr ...
Using ab initio simulations on Fe-Ni-S-C-O-Si liquids, we constrain the origin and composition of the low-velocity layer E′ at the top of Earth's outer core. We find that increasing the concentration of any light element always increases velocity and so a ...
Seismic imaging of the internal Earth has emphasized the inhomogeneity of its mantle. This interface layer of nearly 3000 km surrounding the central metallic core conducts heat released from the latter, which played a significant role in shaping the actual ...
Experimental studies at pressure and temperature conditions of the Earth's lower mantle have shown that iron in ferropericlase (Fp) and in Mg-silicate perovskite (Pv) undergoes a spin state transition. This electronic transition changes elastic and transpo ...
We performed laser-heated diamond anvil cell experiments combined with state-of-the-art electron microanalysis (focused ion beam and aberration-corrected transmission electron microscopy) to study the distribution and valence of iron in Earth's lower mantl ...
The composition of the convecting asthenospheric mantle that feeds the mantle wedge can be investigated via rear-arc lavas that have minimal slab influence. This "ambient mantle wedge" composition (the composition of the wedge prior to the addition of a sl ...
Melt inclusions (MIs) hosted in euhedral olivine have been proposed to represent droplets of primary melt, protected from processes occurring near Earth's surface during eruption. The complex zoning of phosphorus (P) in some olivines and the presence of a ...