Chavan, A., Bhore, V., Bhandari, S.
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2022.115118]
Department of Earth and Environmental Science, K.S.K.V. Kachchh University, Bhuj 370001, India
Copyright Elsevier

Martian geology and surface geomorphic features are grouped under Noachian, Hesperian, and Amazonian eras, based on the crater retention ages and resurfacing ages by crater densities. Comparing the similarities and differences between Martian landforms and their terrestrial analogues promotes an understanding of how surface processes operated on both planets. The study focusses on the processes responsible for the evolution of fluvial valleys flanking volcanic channels and the fluvial terraces with an objective towards ascertaining the role of changing climate, tectonic, and volcanic conditions. We have studied the channels that developed on the flank of volcanic crater Ceraunius Tholus and compared with the monogenetic volcanic field of Dhinodhar Hill which have been significantly modified by fluvial processes. Similarly, the fluvial basins developed on the Hesperian volcanic units of Euhus plateau were compared with the Alaldari drainage of Upper Tapi river basin, showing the development of theater-headed channels and valleys, and relative fluvial features showing the strong influence of catastrophic climate and tectonic, which is also supported by the morphometric analysis in modulating the topography. The fluvial terraces developed in the Nubra and Shyok rivers of Ladakh and Upper and Middle reaches of Sutlej in Central Himalayas are compared with Noctis fossae on Mars both developed due to the interplay of tectonism and climate.

¹Ashley R.Clendenen,²Aleksandr Aleksandrov,^2,3Brant M.Jones,⁴Peter G.Loutzenhiser,⁵Daniel T.Britt,^1,2,3Thomas M.Orlando
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.epsl.2022.117632]
¹School of Physics, Georgia Institute of Technology, Atlanta, 30332-0405, GA, USA
²School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, 30332-0405, GA, USA
³Center for Space Technology and Research, Georgia Institute of Technology, Atlanta, 30332-0405, GA, USA
⁴George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, 30332-0405, GA, USA
⁵Department of Physics, The University of Central Florida, Orlando, FL 32816, USA
Copyright Elsevier

Water and molecular hydrogen evolution from Apollo sample 14163 and lunar regolith simulants LMS-1, a mare simulant, and LHS-1, a highlands simulant, were examined using Temperature Programmed Desorption (TPD) in ultra-high vacuum. LMS-1, LHS-1, and Apollo 14163 released water upon heating, whereas only the Apollo sample directly released measurable quantities of molecular hydrogen. The resulting H2O and H2 TPD curves were fit using a model which considers desorption at the vacuum grain interface, transport in the void space between grain-grain boundaries, molecule formation via recombination reactions and sub-surface diffusion. The model yielded a most probable H2O formation and desorption effective activation energy of ∼150 kJ mol−1 for all samples. The probability distribution widths of the effective activation energies were ∼100–400, ∼100–350, and ∼100–300 kJ mol−1 for LMS-1, LHS-1, and Apollo 14163, respectively. In addition to having the narrowest energy distribution width, the Apollo sample released the least amount to water (103 ppm) relative to LMS-1 (176 ppm) and LHS-1 (195 ppm). Since essentially no molecular hydrogen was observed from the simulants, the results indicate that LMS-1 and LHS-1 display water surface formation, binding, and transport interactions similar to actual regolith but not the desorption chemistry associated with the implanted hydrogen from the solar wind. Overall, these terrestrial surrogates are useful for understanding the surface and interface interactions of lunar regolith grains, which are largely dominated by the terminal hydroxyl sites under both solar wind bombardment and terrestrial preparation conditions.

^1,2Alan E.Rubin,¹Bidong Zhang,³Nancy L.Chabot
Geochmica et Cosmochimica Acta (in Press) Link to Article [https://doi.org/10.1016/j.gca.2022.05.020]
¹Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095-1567, USA
²Maine Mineral & Gem Museum, 99 Main Street, P.O. Box 500, Bethel, ME 04217, USA
³Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA
Copyright Elsevier

Although IVA irons have O- and Cr-isotopic compositions resembling those of equilibrated LL chondrites, the bulk composition of refractory elements (e.g., Re, Ir, Pt) in the IVA core appears to be significantly lower than LL. These compositional discrepancies suggest known IVA irons may be missing early crystallized samples. We hypothesize the bulk composition of the IVA core is LL-like, but current collections do not include early fractional-crystallization IVA products. Our fractional-crystallization modeling of element vs. Au trends suggests that extant IVA irons are products of >40% crystallization of the core, assuming an initial 2.9 wt.% S content. The model-derived bulk (Ni-normalized) composition of the IVA core is depleted relative to LL in most moderate volatiles: S (82% depletion), Ge (99.9% depletion), Ga (95% depletion), As (50% depletion); however, Au is enriched by 10%. Because moderate volatiles with depletions >80% relative to LL have 50%-condensation temperatures <1020 K, it seems likely these depletions reflect post-accretion impact-induced volatilization of the IVA asteroid. The mean Ni-normalized compositions of analyzed IVA irons yield a lesser depletion of As (30%) and greater enrichment of Au (48%) relative to LL. The IVA asteroid may have experienced a complex parent-body thermal and collisional history: (1) differentiation, (2) impact-induced mantle stripping, devolatilization, and fractional condensation, (3) rapid crystallization of the core from the outside inwards, (4) shattering of the core after ∼75% crystallization, (5) quenching of thinly insulated samples (e.g., Fuzzy Creek), (6) formation of amorphous free silica in several IVA irons after impact-induced vaporization of portions of the overlying silicate mantle, followed by fractional condensation, (7) loss of portions of the core representing the first 40% of crystallization, (8) reaccretion of some core fragments, facilitating relatively slow cooling of a few IVA irons (e.g., Duchesne, Duel Hill (1854), Chinautla), and (9) collisional resetting of the Re-Os clock 4456±25 Ma ago.

¹Chi Ma,^2,3Alan E. Rubin
American Mineralogist 107, 1030-1033 Link to Article [http://www.minsocam.org/MSA/AmMin/TOC/2022/Abstracts/AM107P1030.pdf]
¹Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California 91125, U.S.A.
²Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, California 90095-1567, U.S.A.
³Maine Mineral & Gem Museum, 99 Main Street, P.O. Box 500, Bethel, Maine 04217, U.S.A.
Copyright: The Mineralogical Society of America

Zolenskyite (IMA 2020-070), FeCr2S4, is a new sulfide mineral that occurs within troilite, with
clinoenstatite and tridymite, in the matrix of the Indarch meteorite, an EH4 enstatite chondrite.
The mean chemical composition of zolenskyite determined by electron probe microanalysis, is
(wt%) S 43.85, Cr 35.53, Fe 18.94, Mn 0.68, Ca 0.13, total 99.13, yielding an empirical formula of
Fe0.99Mn0.04Ca0.01Cr1.99S3.98. The ideal formula is FeCr2S4. Electron backscatter diffraction shows that
zolenskyite has the C2/m CrNb2Se4-Cr3S4-type structure of synthetic FeCr2S4, which has a = 12.84(1) Å,
b = 3.44(1) Å, c = 5.94(1) Å, β = 117(1)°, V = 234(6) Å3, and Z = 2. The calculated density using the
measured composition is 4.09 g/cm3. Zolenskyite is a monoclinic polymorph of daubréelite. It may be
a high-pressure phase, formed from daubréelite at high pressures (several gigapascals) and moderate
temperatures in highly shocked regions of the EH parent asteroid before becoming incorporated into
Indarch via impact mixing. Zolenskyite survived moderate annealing of the Indarch whole-rock. The
new mineral is named in honor of Michael E. Zolensky, an esteemed cosmochemist and mineralogist at NASA’s Johnson Space Center, for his contributions to research on extraterrestrial materials,
including enstatite chondrites.

¹Hadrien A.R. Devillepoix et al. (>10)
Meteoritics & Plaentary Science (in Press) Open Access Link to Article [https://doi.org/10.1111/maps.13820]
¹School of Earth and Planetary Sciences, Curtin University, Perth, Western Australia, 6845 Australia
Published by arrangement with John Wiley & Sons

On June 19, 2020 at 20:05:07 UTC, a fireball lasting 5.5s was observed above Western Australia by three Desert Fireball Network observatories. The meteoroid entered the atmosphere with a speed of 14.00±0.17  km  s−1 and followed a 58 ° slope trajectory from a height of 75 km down to 18.6 km. Despite the poor angle of triangulated planes between observatories (29°) and the large distance from the observatories, a well-constrained kilo-size main mass was predicted to have fallen just south of Madura in Western Australia. However, the search area was predicted to be large due to the trajectory uncertainties. Fortunately, the rock was rapidly recovered along the access track during a reconnaissance trip. The 1.072 kg meteorite called Madura Cave was classified as an L5 ordinary chondrite. The calculated orbit is of Aten type (mostly contained within the Earth’s orbit), only the second time a meteorite was observed on such an orbit, after Bunburra Rockhole. Dynamical modeling shows that Madura Cave has been in near-Earth space for a very long time. The dynamical lifetime in near-Earth space for the progenitor meteoroid is predicted to be ~87 Myr. This peculiar orbit also points to a delivery from the main asteroid belt via the ν6 resonance, and therefore an origin in the inner belt. This result contributes to drawing a picture for the existence of a present-day L chondrite parent body in the inner belt.

¹P. Rochette,²N. S. Bezaeva,³P. Beck,⁴V. Debaille,⁵L. Folco,¹J. Gattacceca,⁶M. Gounelle,⁷M. Masotta
Meteoritics & Planetary Science (in Press) Link to Article [https://doi.org/10.1111/maps.13825]
¹Aix-Marseille Université, CNRS, IRD, INRAE, CEREGE, 13545 Aix-en-Provence, France
²Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, 19, Kosygin Str., 119991 Moscow, Russia
³Université Grenoble Alpes, CNRS, IPAG, 38400 Grenoble, France
⁴Laboratoire G-Time, Université Libre de Bruxelles, 1050 Brussels, Belgium
⁵Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy
⁶IMPMC, CNRS – UMR 7590, Sorbonne Université, Muséum national d’Histoire naturelle, 75005 Paris, France
⁷Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy
Published by arrangement with John Wiley & Sons

During the systematic magnetic susceptibility survey of the Paris Museum Australasian tektite collection, we identified three previously overlooked occurrences of volcanic glass that resembles tektites, based on anomalous magnetic properties, high water content, the presence of microcrystals, and anomalous chemical composition. These occurrences are from the Phu Yen province in south-central Vietnam (two rhyolitic glass fragments) and from the Philippines: one from northern Luzon Island (a basaltic rounded etched glass), one from Santa Mesa near Manilla (a dozen small rounded rhyolitic gravels). The two occurrences in the Philippines are quite similar to previously described volcanic glasses from the nearby Pagudpod and Nagcarlan localities, respectively. The rhyolitic glass specimens from the Phu Yen province are the first documentation of a geological occurrence of obsidian in Vietnam. This work is a warning note that glass samples with anomalous properties found among tektite collections may correspond to volcanic pseudotektites instead of real tektites with anomalous composition. The basaltic glass sample from the Philippines locally shows microcrystalline quench textures previously unknown in natural samples. These findings may also be of interest for archeologists involved in glass artifacts sourcing.

^1,2,3Lixin Gu,^1,3Sen Hu,^4,5Mahesh Anand,^1,2,3Xu Tang,^1,3,6Jianglong Ji,⁷Bin Zhang,^1,3,6Nian Wang,^1,3,6Yangting Lin
American Mineralogist 107, 1018-1029 Link to Article [http://www.minsocam.org/MSA/AmMin/TOC/2022/Abstracts/AM107P1018.pdf]
¹Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
²Electron Microscopy Laboratory, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
³Innovation Academy for Earth Science, Chinese Academy of Sciences, Beijing 10029, China
⁴School of Physics Sciences, The Open University, Kents Hill, Milton Keynes MK7 6AA, U.K.
⁵Department of Earth Sciences, The Natural History Museum, Cromwell Road, London SW7 5BD, U.K.
⁶University of Chinese Academy of Sciences, Beijing 100049, China
⁷Analytical and Testing Center of Chongqing University, Chongqing 400044, China
Copyright: The Mineralogical Society of America

We report on the discovery of two high-pressure minerals, tuite and ahrensite, located in two
small shock-induced melt pockets (SIMP 1 and 2) in the Zagami martian meteorite, coexisting with
granular and acicular stishovite and seifertite. Tuite identified in this study has two formation pathways: decomposition of apatite and transformation of merrillite under high-P-T conditions. Chlorinebearing products, presumably derived from the decomposition of apatite, are concentrated along the
grain boundaries of tuite grains. Nanocrystalline ahrensite in the pyroxene clast in SIMP 2 is likely
to be a decomposition product of pigeonite under high-P-T conditions by a solid-state transformation
mechanism. The pressure and temperature conditions estimated from the high-pressure minerals in
the shock-induced melt pockets are ~12–22 GPa and ~1100–1500 °C, respectively, although previous
estimates of peak shock pressure are higher. This discrepancy probably represents the shift of kinetic
relative to thermodynamic phase boundaries, in particular the comparatively small region that we
examine here, rather than a principal disagreement between the peak shock conditions.

¹Kashima, Aruto,²Urashima, Shu-hei,^1,2Yui, Hiroharu
Journal of Raman Spectroscopy (in Press) Open Access Link to Article [DOI 10.1002/jrs.6355]
¹Department of Chemistry, Faculty of Science, Tokyo University of Science, Tokyo, Japan
²Water Frontier Research Center, Research Institute for Science and Technology, Tokyo University of Science, Tokyo, Japan

We currently do not have a copyright agreement with this publisher and cannot display the abstract here

^1,2,3Natsuki Hosono,⁴Shun-ichiro Karato
Journal of Geophysical Research (Planets) (in Press) Link to Article [https://doi.org/10.1029/2021JE006971]
¹Department of Planetology, Kobe University, Kobe, Japan
²RIKEN Center for Computational Science, Kobe, Japan
³Japan Agency for Marine-Earth Science and Technology, Yokohama, Japan
⁴Department of Earth and Planetary Sciences, Yale University, New Haven, CT, USA
Published by arrangement with John Wiley & Sons

We explore the role of various equations of state (EoS) in controlling the composition of the Moon formed by a giant impact (GI) using a density-independent SPH code. A limitation in our previous model Hosono et al. (2019), https://doi.org/10.1038/s41561-019-0354-2 is improved by replacing the EoS of the solid from Tillotson EoS to M-ANEOS, and we also explored two recently proposed EoSs by Stewart et al. (2020), https://doi.org/10.1063/12.0000946 and Wissing and Hobbs (2020a), https://doi.org/10.1051/0004-6361/201935814; Wissing and Hobbs (2020b), https://doi.org/10.1051/0004-6361/201936227. The goal is to investigate to what extent we can explain the observed composition of the Moon including the similarity in the isotopic composition and the dissimilarity in the FeO/(FeO + MgO) ratio as compared to that of Earth by the different types of EoS assuming the conventional collision conditions. We found that changing the EoS for solids from Tillotson to M-ANEOS EoS resolves the issues of latent heat, but its effect on the composition of the disk is small compared to the influence of the hard-sphere EoS of magma ocean in controlling the composition of the disk. Similarly, two recently proposed EoSs have small effects on the composition of the disk in comparison to the model where the hard-sphere EoS is used for preexisting magma ocean. We attribute this difference to a fundamental difference in thermodynamic behavior of silicate melts captured by the hard-sphere EoS and by newly proposed EoSs; in the hard-sphere model of silicate melts, configurational entropy dominates in free energy, whereas in the newly proposed model, entropy is dominated by vibrational entropy similar to entropy of solids.

¹Cyril Sturtz,¹Angela Limare,¹Marc Chaussidon,¹Édouard Kaminski
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2022.115100]
¹Université Paris Cité, Institut de Physique du Globe de Paris, CNRS, Paris, F-75005, France
Copyright Elsevier

Meteorites are interpreted as relics of early formed planetary bodies, and they provide information about the processes that occurred in the first few of our solar system. The ages measured for some differentiated meteorites (achondrites), indicate that planetesimals formed a differentiated silicate crust as early as after the beginning of the solar system. The composition of the recently discovered achondrite Erg Chech 002 (EC002), the oldest andesitic rock known so far, betokens partial melting of a chondritic source taking place as early as before all other known achondrites. However, thermal models of early accreted planetesimals predict massive melting of the planetesimal during core/mantle differentiation and cannot account for the preservation of a substantial amount of chondritic material. In this paper, we propose a way to interpret petrological and geochemical constraints provided by differentiated meteorites by introducing a refined thermal model of planetesimals formation and evolution. We demonstrate that continuous, protracted accretion of cold undifferentiated material upon a magma ocean over a timescale 2 times larger than the lifetime of the 26Al heat source leads to the preservation of a few km thick chondritic crust. During accretion, the heat released by radioactive decay further induces episodes of partial melting at the base of the crust, which can led to the formation of andesitic rocks such as EC002. Using the available constraints on the age of EC002 and its cooling rate, the application of our model constraints the terminal radius of its parent body between 70 and .