The monzonorite-anorthosite connection: The petrogenesis of terrestrial KREEP

There is a suite of rocks typically associated with Proterozoic massif anorthosites that bear some interesting similarities to lunar KREEP. In many cases these rocks are plutonic and have traditionally been referred to as the jotunite-mangerite-+/-charnockite-+/-syenite suite. However, in the Rogaland district of southwestern Norway, where they are referred to as 'monzonorites', these rocks are also present as fine-grained dikes and as the chill margin of a layered intrusion, and thus approximate magmatic liquid compositions are readily obtained by chemical analysis. Monzonorites are typically enriched in incompatible lithophile elements such as K (alkali feldspar is present), the rare earths (REE), and P. They have intermediate to low Mg', low-Ca pyroxene, and more evolved types have low Ti/Sm ratios. Much debate has developed over attempts to explain the link between monzonorites and massif anorthosites. One feature seems clear: monzonorites and associated anorthosites have different initial isotopic ratios, so a simple relation is not possible. However, there is apparently a continuum in major elements between the monzonorites and gabbros believed to represent magmas parental to the anorthosites. This continuum suggests a link via high pressure fractionation coupled with assimilation. Although more complicated, this scenario is similar to that evoked for the early Moon: following the formation of ferroan anorthosites, continued fractional crystallization of the residual liquids at the base of the crust led to the formation of KREEP. An attempt is made here to establish a link between monzonorites and high-Al gabbros which are nearly always found as ancillary intrusions associated with anorthosites, and which may record processes in lower crustal magma chambers

Geochemistry of cumulates from the Bjerkreim-Sokndal layered intrusion (S. Norway). Part II. REE and the trapped liquid fraction

Rare earth elements in bulk cumulates and in separated minerals (plagioclase, apatite, Ca-poor and Ca-rich pyroxenes, ilmenite and magnetite) from the Bjerkreim-Sokndal layered intrusion (Rogaland Anorthosite Province, SW Norway) are investigated to better define the proportion of trapped liquid and its influence on bulk cumulate composition. In leuconoritic rocks (made up of plagioclase, Ca-poor pyroxene, ilmenite, magnetite, olivine), where apatite is an intercumulus phase, even a small fraction of trapped liquid significantly affects the REE pattern of the bulk cumulate, together with cumulus minerals proportion and composition. Contrastingly, in gabbronoritic cumulates characterized by the presence of cumulus Ca-rich pyroxene and apatite, cumulus apatite buffers the REE content. La/Sm and Eu/Eu* VS. P2O2 variations in leuconorites display mixing trends between a pure adcumulate and the composition of the trapped liquid, assumed to be similar to the parental magma. Assessment of the trapped liquid fraction in leuconorites ranges from 2 to 25% and is systematically higher in the north-eastern part of the intrusion. The likely reason for this wide range of TLF is different cooling rates in different parts of the intrusion depending on the distance to the gneissic margins. The REE patterns of liquids in equilibrium with primitive cumulates are calculated with mass balance equations. Major elements modelling (Duchesne, J.C., Charlier, B., 2005. Geochemistry of cumulates from the Bjerkreiin-Sokndal layered intrusion (S. Norway): Part I. Constraints from major elements on the mechanism of cumulate formation and on the jotunite liquid line of descent. Lithos. 83, 299-254) permits calculation of the REE content of melt in equilibrium with gabbronorites. Partition coefficients for REE between cumulus minerals and a jotunitic liquid are then calculated. Calculated liquids from the most primitive cumulates are similar to a primitive jotunite representing the parental magma of the intrusion, taking into account the trapped liquid fraction calculated from the P2O5 content. Consistent results demonstrate the reliability of liquid compositions calculated from bulk cumulates and confirm the hypothesis that the trapped liquid has crystallized as a closed-system without subsequent mobility of REE in a migrating interstitial liquid. (c) 2005 Elsevier B.V. All rights reserved

LINE INTENSITIES AND BROADENING COEFFICIENTS FROM HIGH RESOLUTION FAR INFRARED SPECTRA

Molecular lines observed in high resolution far infrared spectra are associated with pure rotation transitions or belong to low-energy vibrational bands. Together with other parameters characterizing them, the intensities and broadening coefficients of these lines are required for example to analyze spectra of planetary atmospheres or to gain insight into the physics of the studied molecules or intermolecular interactions. Pure rotation line intensities can also be used to determine the particle density of chemically unstable species, allowing to obtain line intensities in another spectral range as was for example done for hypochlorous acid\footnote{J. Vander Auwera, J. Kleffmann, J.-M. Flaud, G. Pawelke, H. B\"{u}rger, D. Hurtmans, R. P\'etrisse, J. Mol. Spectrosc. 204 (2000) 36--47.} and ozone.\footnote{B.J. Drouin, T.J. Crawford, S. Yu, J. Quant. Spectrosc. Radiat. Transf. 203 (2017) 282--292.} This lecture will deal with the measurement of the intensities and broadening coefficients of molecular lines observed in high resolution far infrared absorption spectra. It will skim over measurements carried out using THz spectroscopy and focus on Fourier transform spectroscopy. This latter technique is now commonly associated with synchrotron radiation, the high brightness and highly collimated nature of which being big advantages at low energies over conventional sources such as mercury lamps.\footnote{A.R.W. McKellar, J. Mol. Spectrosc. 262 (2010) 1--10.} The lecture will present and discuss some recent and ongoing measurements carried out relying on Fourier transform far infrared spectra recorded using synchrotron radiation, highlighting some aspects specific to these retrievals

LINE INTENSITY MEASUREMENTS AND ANALYSIS IN THE ν3 BAND OF RUTHENIUM TETROXIDE

Ruthenium tetroxide (RuO$_4$) is a heavy tetrahedral molecule characterized by an unusual volatility near ambient temperature. Because of its chemical toxicity and the radiological impact of its $^{103}$Ru and $^{106}$Ru isotopologues, the possible remote sensing of this compound in the atmosphere has renewed interest in its spectroscopic properties. In a recent study, the strong fundamental band associated with the excitation of the infrared active stretching mode $\nu_3$ of $^{102}$Ru$^{16}$O$_4$, observed near 10 $\mu$m, was re-investigated at high-resolution (0.001 cm$^{-1}$) with the help of a $^{102}$Ru isotopically pure sample.\footnote{S. Reymond-Laruinaz, V. Boudon, L. Manceron, L. Lago, D. Doizi, J Mol Spectrosc 315 (2015) 46--54.} Building upon that work, the present contribution is the first investigation dealing with high-resolution line-by-line intensity measurements for the $\nu_3$ fundamental band of $^{102}$Ru$^{16}$O$_4$. It relies on high resolution Fourier transform infrared spectra specifically recorded at room temperature at the AILES beam line of SOLEIL using synchrotron radiation, a specially constructed cell and an isotopically pure sample of $^{102}$Ru$^{16}$O$_4$. Relying on an effective Hamiltonian and associated effective dipole moment,$^{a}$ the measured line intensities were assigned and dipole moment parameters determined. A HITRAN-formatted frequency and intensity line list was generated

A mineralogical and microstructural study of 7 eucrites (A-881394, Y-791195, Y-981617, Y-790266, Y-791186, Y-792510, Y-793591).

第3回極域科学シンポジウム/第35回南極隕石シンポジウム 11月29日（木） 国立国語研究所 2階講

SELF BROADENING COEFFICIENTS AND IMPROVED LINE INTENSITIES FOR THE v7 BAND OF C2H4 NEAR 10.5 µm, AND IMPACT ON ETHYLENE RETRIEVALS FROM JUNGFRAUJOCH SOLAR SPECTRA

Relying on high-resolution Fourier transform infrared (FTIR) spectra, the present work involved extensive measurements of individual line intensities and self-broadening coefficients for the ν7 band of 12C2H4. The measured self-broadening coefficients exhibit a dependence on both J and Ka. Compared to the corresponding information available in the latest edition of the HITRAN spectroscopic database, the measured line intensities were found to be higher by about 10 % for high J lines in the P branch and lower by about 5 % for high J lines of the R branch, varying between these two limits roughly linearly with the line positions. The impact of the presently measured line intensities on retrievals of atmospheric ethylene in the 949.0–952.0cm 1 microwindow was evaluated using a subset of ground-based high-resolution FTIR solar spectra recorded at the Jungfraujoch station. The use of HITRAN 2012 with line intensities modified to match the present measurements led to a systematic reduction of the measured total columns of ethylene by -4.1 +/- 0.1 %

Some results on the role of P, T, and fO2 on ilmenite composition

peer reviewe

What modulates eruptive styles at Villarrica and Osorno volcanoes (Chile)?

Villarrica and Osorno are two active stratovolcanoes in the Central Southern Volcanic Zone (CSVZ) of the Chilean Andes that share several geochemical characteristics: near-primary, tholeiitic parent magmas (50-53 wt. % SiO2), overlapping major/trace element differentiation trends, and comparable storage conditions [1-4]. Yet, their eruptive styles contrast each other significantly. Villarrica is a steady-state, open-vent stratovolcano with a lava lake since 1985, which produced ~100 low to moderate intensity Strombolian eruptions and lava flows since 1579 CE. Osorno is a closed-vent stratovolcano with 10x less eruptions for the same period. We initially proposed that differences in eruptive style and frequency could be due to a relatively higher degree of crustal permeability under Villarrica than Osorno due to the Liquiñe-Ofqui Fault Zone [5]. Preliminary analyses show that both volcanoes have broadly similar olivine chemistry ranges and multimodal distributions, with minor differences in olivine and melt chemistry/textures between Villarrica (Fo72-87) and Osorno (Fo66-82) [4,5]. Diffusion timescales for both volcanoes are mostly 250 days. This suggests the degree of crustal permeability underneath the volcanoes are likely comparable, prompting consideration of other factors. In this contribution, we evaluate the role of magma supply rate, storage conditions, and slab input in modulating eruptive styles at Osorno and Villarrica based on an updated dataset of magma storage conditions, diffusion timescales, geochemical data compilations, and inferences drawn from published literature. We find that magma storage conditions of both volcanoes are similar to each other at T~1100°C, P~200 MPa, along with comparable input of fluids released from the down-going slab. The multimodality in olivine chemistry, diversity in types of olivine growth zones and textures, timescale ranges, coupled with the relatively high magma supply rate estimates for Villarrica from the literature suggest magma supply rate could modulate eruptive style at Villarrica and Osorno. With this contribution, we aim to further current understanding of subduction zone magmatism and geodynamics, with implications on volcanic hazard reduction. 1. Vergara et al. (2004). J. S. Am. Earth Sci. 17: 227-238. 2. Morgado et al. (2015). JVGR, 306: 1-16. 3. Pizarro et al. (2019). JVGR. 384: 48-63. 4. Bechon et al. (2022). Lithos. 106777. 5. Romero et al. (2022). Bull. Volc. 85 (2)