Formation of N–С–О–Н molecules and complexes in the basalt–basaltic andesite melts at 1.5 Gpa and 1400°C in the presence of liquid iron alloys

Redox control on nitrogen isotope fractionation during planetary core formation

“…Nitrogen partition coefficients between the metal and silicate phases, D N metal-silicate , were calculated as D N metal-silicate = C N metal/ C N silicate , where C N metal and C N silicate are the average N contents (wt%) of the metal alloys and silicate glasses, respectively (Table 1). With decreasing f O 2 from ΔIW −0.45 to −3.13, D N metal-silicate decreases from 7 ± 2 to 0.2 ± 0.2, consistent with previous experimentally determined partition coefficients (15–22, 52, 53) (Fig. 1).…”

“…Previous studies of N partitioning between metal and silicate phases (15, 17–22, 38) presented N abundance data obtained by electron probe microanalysis (EPMA). This in situ analytical method allows measuring N contents in metal alloys and silicate glasses in a polished section of an experimental charge with a detection limit as low as 0.03 wt% (17, 39) but is not adapted to isotopic measurements.…”

“…Recent studies have revealed that a significant fraction of N could have been segregated into the core during the late stages of core formation (15–22). Investigation of the effect of core formation on the evolution of the bulk mantle δ 15 N value requires knowledge of the N-isotopic fractionation factors between metal and silicate phases.…”

“…24, 26, and 28). Recent studies have shown f O 2 to be the main control on N partitioning during metal–silicate segregation (17–22) because it determines the N speciation in the silicate phase (17, 29). N speciation, in turn, is expected to dictate ∆ 15 N metal-silicate (29).…”

Experimental modeling of formation of native metals (Fe, Ni, Co) in the earth’s crust by the interaction of hydrogen with basaltic melts

“…Согласно ранее полученным данным по растворимости водорода в силикатных расплавах, предельная растворимость водорода в них при параметрах опытов составляет около ~7•10 −3 мас.% (Персиков и др., 1986), т.е. примерно на два порядка меньше предельной растворимости воды при тех же значениях температуры и давления (Luth et al, 1987;Persikov et al, 1990;Kadik et al, 2015Kadik et al, , 2017Куровская и др., 2018). Растворимость водорода в расплаве железа при атмосферном давлении и температуре 1600°С равна примерно 2.5•10 −3 мас.% (Галактионова, 1967), а в металлическом γ-Fe при 1250°C и 100 МПа -около 4•10 −2 мас.%, т.е.…”