A newly revised estimation of bulk densities and examination of the shape of individual Ryugu grains by Akiko Miyazaki, Toru Yada, Kasumi Yogata, Kentaro Hatakeda, Aiko Nakato, Masahiro Nishimura, Kana Nagashima, Kazuya Kumagai, Yuya Hitomi, Hiromichi Soejima, Rui Tahara, Rei Kanemaru, Arisa Nakano, Miwa Yoshitake, Ayako Iwamae, Shizuho Furuya, Akira Tsuchiyama, Shogo Tachibana, Tatsuhiro Michikami, Tatsuaki Okada, Masanao Abe, Tomohiro Usui

“…The obtained average bulk density value of A + C samples was almost the same as that of 16 Ryugu grains estimated based on CT scanned data, and was consistent with the densities of CI chondrites (1.57–1.91 g/cm3). The axial ratios of the grains in Chambers A and C were similar and those of the 724 returned samples and the flying particles ejected during the sampling operations were also similar, suggesting that relatively small Ryugu materials (mm‒cm in size) are similar in shape. …”
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The generation and evolution of the Archean continental crust: The granitoid story in southeastern Brazil by Rodrigo S. Marimon, Chris J. Hawkesworth, Elton L. Dantas, Rudolph A.J. Trouw, Wilson Teixeira, Peter C. Hackspacher, Allen Fetter, Ciro A. Ávila, Silvia Volante, Atlas V. Corrêa Neto, Everton M. Bongiolo, Rodrigo Vinagre, Maurício Simon

“…The rocks are divided into three main geochemical groups with different ages: (1) TTG (3.02–2.77 Ga); (2) medium- to high-K granitoids (2.85–2.72 Ga); and (3) A-type granites (2.7–2.6 Ga). The juvenile to chondritic (Hf-Nd isotopes) TTG were divided into two sub-groups, TTG 1 (low-HREE) and 2 (high-HREE), derived from partial melting of metamafic rocks similar to those from adjacent greenstone belts. …”
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Radiogenic Hf isotopic compositions of continental eolian dust from Asia, its variability and its implications for seawater Hf by Pettke, T, Lee, D, Halliday, A, Rea, D

“…It monitors the composition of continental crust exposed to erosion in Asia. 176Lu/177Hf ratios of modern dust are sub-chondritic between 0.011 and 0.016 but slightly elevated with respect to immature sediments. …”

Rare earth element geochemistry of Middle Devonian reefal limestones of the Dianqiangui Basin, South China: implications for nutrient sources and expansion of the reef ecosystem by Qi Mao, Shangyi Gu, Huan Li, Gary G. Lash, Tianyi Zhang, Xiaofeng Xie, Zidong Guo

“…In contrast, REY patterns of the Upper Buzhai reef section samples are similar to those of modern seawater characterized by light rare earth element (LREE) depletion (average (Pr/Yb)N = 0.76), negative Ce anomalies (average Ce/Ce* = 0.88), and average super-chondritic Y/Ho ratios (average = 45.4)). Slightly positive Eu anomalies (Eu/Eu* = 0.93–1.94; average = 1.36) of the Upper Buzhai reef section samples are attributed to the negligible effect of hydrothermal fluids. …”
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Sr, Nd, Pb and trace element systematics of the New Caledonia harzburgites: Tracking source depletion and contamination processes in a SSZ setting by Arianna Secchiari, Alessandra Montanini, Delphine Bosch, Patrizia Macera, Dominique Cluzel

“…The harzburgites are characterised by remarkably low REE concentrations (<0.1 chondritic values) and display ''U-shaped'' profiles, with steeply sloping HREE (DyN/YbN = 0.07–0.16) and fractionated LREE-MREE segments (LaN/SmN = 2.1–8.3), in the range of modern fore-arc peridotites. …”
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Magmatic PGE Sulphide Mineralization in Clinopyroxenite from the Platreef, Bushveld Complex, South Africa by Reiner Klemd, Andreas Beinlich, Matti Kern, Malte Junge, Laure Martin, Marcel Regelous, Robert Schouwstra

“…This is in accordance with the εNd (2.06 Ga) (chondritic uniform reservoir (CHUR)) values, of −6.16 to −6.94, which are similar to those of the magmatic pyroxenite and norite of the Main Zone and the Platreef in the northern sector of the northern Bushveld limb. …”
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Iron oxidation state in serpentines and magnesian chlorites of subduction-related rocks by B. Reynard, C. Fellah, C. McCammon

“…<p>The ferric iron content in hydrothermally altered ultrabasic rocks and their major minerals, serpentines and Mg-chlorites, is important for establishing the oxidation state budget from oceanic ridges to subduction zones, in carbonaceous chondrites, and for modeling phase equilibria. A compilation of literature Mössbauer spectroscopic data on serpentines and magnesian chlorites from high-pressure ophiolites yields much lower ferric-to-total-iron ratios (Fe<span class="inline-formula">³⁺</span> <span class="inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" id="M2" display="inline" overflow="scroll" dspmath="mathml"><mo>/</mo></math><span><svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="8pt" height="14pt" class="svg-formula" dspmath="mathimg" md5hash="527256ea34e0af356380afd605ccefc0"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="ejm-34-645-2022-ie00001.svg" width="8pt" height="14pt" src="ejm-34-645-2022-ie00001.png"/></svg:svg></span></span> Fe<span class="inline-formula">_total</span>) than those obtained on similar samples by X-ray absorption near-edge spectroscopy (XANES), leading to contradictory estimates of the ferric iron budget of subduction zones. …”
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A low initial abundance of (CM)-C-247 in the early solar system and implications for r-process nucleosynthesis by Stirling, C, Halliday, A, Potter, E, Andersen, M, Zanda, B

“…Uranium isotopic results for almost 40 different phases show no resolvable deviations in 235U/238U from the chondritic value, at the ∼ 1-2 epsilon level. These data supplement our previous observations for a suite of bulk meteorite samples [C.H. …”

Zircon within chromitite requires revision of the tectonic history of the Eoarchean Itsaq Gneiss complex, Greenland by Hikaru Sawada, Tomoaki Morishita, Adrien Vezinet, Richard Stern, Kenichiro Tani, Ikuya Nishio, Kanta Takahashi, D. Graham Pearson, Kristoffer Szilas

“…The least altered zircons from a chromitite exhibited initial Hf isotope ratios of 0.28078 – 0.28084 (i.e., initial εHf value of − 1.1 to − 0.4), close the chondritic value at ca. 3.0 Ga and the depleted mantle at ca. 3.2 Ga. …”
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