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Related papers: Origin of isolated olivine grains in carbonaceous …

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We report combined oxygen isotope and mineral-scale trace element analyses of amoeboid olivine aggregates (AOA) and chondrules in ungrouped carbonaceous chondrite Northwest Africa 5958. The trace element geochemistry of olivine in AOA, for…

Earth and Planetary Astrophysics · Physics 2018-12-11 Emmanuel Jacquet , Yves Marrocchi

We report trace element concentrations of silicate phases in chondrules from LL3 ordinary chondrites Bishunpur and Semarkona. Results are similar to previously reported data for carbonaceous chondrites, with rare earth element (REE)…

Earth and Planetary Astrophysics · Physics 2015-03-12 Emmanuel Jacquet , Olivier Alard , Matthieu Gounelle

We report trace element analyses by laser ablation inductively coupled plasma mass spectrometry of metal grains from 9 different CR chondrites, distinguishing grains from chondrule interior ("interior grains"), chondrule surficial shells…

Earth and Planetary Astrophysics · Physics 2015-02-09 Emmanuel Jacquet , Marine Paulhiac-Pison , Olivier Alard , Anton T. Kearsley , Matthieu Gounelle

We report in situ LA-ICP-MS trace element analyses of silicate phases in olivine-bearing chondrules in the Sahara 97096 (EH3) enstatite chondrite. Most olivine and enstatite present rare earth element (REE) patterns comparable to their…

Earth and Planetary Astrophysics · Physics 2016-06-02 Emmanuel Jacquet , Olivier Alard , Matthieu Gounelle

Presolar grains are trace components in chondrite matrices. Their abundances and compositions have been systematically studied in carbonaceous chondrites but rarely in situ in other major chondrite classes. We have conducted a NanoSIMS…

Earth and Planetary Astrophysics · Physics 2022-09-07 Jens Barosch , Larry Nittler , Jianhua Wang , Elena Dobrică , Adrian J. Brearley , Dominik C. Hezel , Conel M. O'D. Alexander

Low-iron, manganese-enriched (LIME) olivine grains are found in cometary samples returned by the Stardust mission to comet 81P/Wild 2. Similar grains are found in primitive meteoritic clasts and unequilibrated meteorite matrix. LIME olivine…

Earth and Planetary Astrophysics · Physics 2023-07-04 Denton S. Ebel , Michael K. Weisberg , John R. Beckett

We report trace element analyses from mineral phases in chondrules from carbonaceous chondrites (Vigarano, Renazzo and Acfer 187), carried out by laser ablation inductively coupled plasma mass spectrometry. Results are similar in all three…

Earth and Planetary Astrophysics · Physics 2015-02-09 Emmanuel Jacquet , Olivier Alard , Matthieu Gounelle

We report a correlated NanoSIMS-transmission electron microscopy study of the ungrouped carbonaceous chondrite Northwest Africa (NWA) 5958. We identified 10 presolar SiC grains, 2 likely presolar graphite grains, and 20 presolar silicate…

Earth and Planetary Astrophysics · Physics 2019-10-16 Larry R. Nittler , Rhonda M. Stroud , Conel M. O'D. Alexander , Kaitlin Howell

Presolar oxide grains have been previously divided into several groups (Group 1 to 4) based on their isotopic compositions, which can be tied to several stellar sources. Much of available data was acquired on large grains, which may not be…

Solar and Stellar Astrophysics · Physics 2022-05-04 Nan Liu , Nicolas Dauphas , Sergio Cristallo , Sara Palmerini , Maurizio Busso

The insoluble organic matter (IOM) of an unequilibrated enstatite chondrite Sahara (SAH) 97096 has been investigated using a battery of analytical techniques. As the enstatite chondrites are thought to have formed in a reduced environment…

Refractory inclusions in chondritic meteorites, namely amoeboid olivine aggregates (AOAs) and Ca-Al-rich inclusions (CAIs), are among the first solids to have formed in the solar system. The isotopic composition of CAIs is distinct from…

Earth and Planetary Astrophysics · Physics 2024-01-15 Christian A. Jansen , Christoph Burkhardt , Yves Marrocchi , Jonas M. Schneider , Elias Wölfer , Thorsten Kleine

We report the identification of presolar silicates (~177 ppm), presolar oxides (~11 ppm), and one presolar SiO2 grain in the Allan Hills (ALHA) 77307 chondrite. Three grains having Si isotopic compositions similar to SiC X and Z grains were…

Solar and Stellar Astrophysics · Physics 2010-08-03 Ann N. Nguyen , Larry R. Nittler , Frank J. Stadermann , Rhonda M. Stroud , Conel M. O'D. Alexander

We obtained mid-infrared spectra of chondrules, matrix, CAIs and bulk material from primitive type 1-4 chondrites in order to compare them with the dust material in young, forming solar systems and around comets. Our aim is to investigate…

Earth and Planetary Astrophysics · Physics 2023-01-02 A. Morlok , C. M. Lisse , A. B. Mason , E. S. Bullock , M. M. Grady

NanoSIMS C-, N-, and O-isotopic mapping of matrix in CO3.0 chondrite Dominion Range (DOM) 08006 revealed it to have in its matrix the highest abundance of presolar O-rich grains (257 +76 / -96 ppm, 2$\sigma$) of any meteorite. It also has a…

Earth and Planetary Astrophysics · Physics 2018-03-14 Larry R. Nittler , Conel M. O'D. Alexander , Jemma Davidson , My E. I. Riebe , Rhonda M. Stroud , Jianhua Wang

Compound chondrules, i.e. chondrules fused together, make a powerful probe of the density and compositional diversity in chondrule-forming environments, but their abundance among the dominating porphyritic textures may have been drastically…

Earth and Planetary Astrophysics · Physics 2021-01-26 Emmanuel Jacquet

Olivine comprises approximately 70 $\%$ by volume of the Earth's upper mantle, making it likely that it controls the mechanical, electrical and seismic properties of the upper mantle. All rocks are composed of crystals separated by grain…

We obtained [O III] narrow-band imaging and multi-slit MXU spectroscopy of the blue compact dwarf (BCD) galaxy NGC 1705 with FORS2@VLT to derive chemical abundances of PNe and H II regions and, more in general, to characterize the…

Astrophysics of Galaxies · Physics 2015-10-21 F. Annibali , M. Tosi , A. Pasquali , A. Aloisi , M. Mignoli , D. Romano

Isotopic anomalies in chondrules hold important clues about the dynamics of mixing and transport processes in the solar accretion disk. These anomalies have been interpreted to indicate either disk-wide transport of chondrules or local…

Earth and Planetary Astrophysics · Physics 2020-09-21 Jonas M. Schneider , Christoph Burkhardt , Yves Marrocchi , Gregory A. Brennecka , Thorsten Kleine

Nitrogen-bearing complex organic molecules have been commonly detected in the gas phase but not yet in interstellar ices. This has led to the long-standing question of whether these molecules form in the gas phase or in ices. $\textit{James…

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