Meteoritics & Planetary Science最新文献

{"title":"Impactor identification with spallogenic Cr isotopes: The Wabar impact craters (Saudi Arabia)","authors":"Aryavart Anand,&nbsp;Klaus Mezger,&nbsp;Beda Hofmann","doi":"10.1111/maps.14242","DOIUrl":"10.1111/maps.14242","url":null,"abstract":"<p>Precise measurements of Cr isotopic composition of terrestrial impactites have successfully provided evidence for the presence of extraterrestrial material and have, in some cases, allowed the identification of the type of impactor responsible for the formation of the impact structure. The high Cr abundance in most meteorite groups aids in detecting extraterrestrial contamination while their distinct isotopic compositions can help with the identification of the nature of the projectile. However, this common approach of detection and identification of extraterrestrial contamination using mass-independent ⁵³Cr and ⁵⁴Cr variations fails when the impactor type is an iron meteorite because of their low Cr abundances (which are in a similar range to terrestrial rocks). The present study demonstrates the viability of a spallogenic Cr contribution in iron meteorites (resulting from their long cosmic ray exposure times), which compensates for their low Cr abundances and facilitates the identification of iron-meteoritic contamination in terrestrial impactites. Thus, it broadens the scope of impactors (and impactites) that can be investigated using mass-independent Cr isotopes from solely chondrites and primitive achondrites to include iron meteorites. The Wabar impact craters are an optimal candidate for this study, characterized by low weathering, diverse impactites, partial meteorite survival, substantial impactor material contamination, and a felsic target lithology with low background Cr concentration. The Cr isotopic composition of the Wabar background sand, which represents the target lithology, is indistinguishable from the terrestrial Cr isotopic composition range, whereas the Wabar iron meteorites show coupled spallogenic excesses in ε⁵³Cr and ε⁵⁴Cr. The Cr isotopic compositions of Wabar impactites show resolved deviations from the terrestrial Cr isotopic composition, thereby indicating the presence of Wabar meteoritic contamination. Moreover, the study demonstrates that even an impactor with a non-carbonaceous chondritic origin, such as a IIIAB iron meteorite, can have a carbonaceous chondrite-like signature in ε⁵⁴Cr anomalies due to spallogenic Cr contamination. The study advocates for a comprehensive investigation combining platinum group elements and Cr (and/or Ni, Ru) isotopes to accurately characterize impactor types.</p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 10","pages":"2651-2659"},"PeriodicalIF":2.2,"publicationDate":"2024-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/maps.14242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141821322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The “suevite” conundrum, Part 2: Re-examining the type locality at the Ries impact structure, Germany","authors":"Gordon R. Osinski,&nbsp;Richard A. F. Grieve","doi":"10.1111/maps.14241","DOIUrl":"10.1111/maps.14241","url":null,"abstract":"<p>One of the most common types of allochthonous impactite produced in hypervelocity impact events is impact breccia that contains melt particles. In numerous terrestrial hypervelocity impact structures such melt-bearing breccias have been termed “suevite,” after the type locality at the Ries impact structure, Germany. Despite its widespread occurrence, the origin, emplacement, and classification of suevite remains debated. In this contribution, we re-examine the nature and origin of suevite at the Ries impact structure. The results of new field and laboratory investigations, when combined and synthesized with results from previous studies, lead to a multi-stage model for the origin and emplacement of allochthonous impactites during the Ries impact event. Following the creation of a transient cavity the so-called Bunte Breccia and “megablocks” were emplaced via ballistic sedimentation and subsequent radial flow during the excavation stage to form a continuous ejecta blanket. At the end of the excavation stage, a mixture of melt and lithic fragments formed a lining to the transient cavity and it is this material that later became the crater, dike, and outer suevite (OS) units. The crater suevite represents the material from the displaced zone of the transient cavity that was transported and mixed but never left the cavity. The emplacement of dike suevite occurred during the modification stage as the crater suevite was intruded into fractures in the underlying crater floor. The OS and rare impact melt rocks overlying the ballistic (Bunte Breccia) ejecta deposits were emplaced as outwards-directed ground-hugging flows largely during the modification stage of crater formation. The OS flows varied both spatially and temporally in terms of the flow characteristics, from being dominated by solid particles and gas (cf. pyroclastic density currents) to a mixture of solid particles, liquid (impact melt), and minor gases (i.e., particulate impact melt-rich flows). These particulate impact melt-rich flows dominated by far. Minor “fallback” of material from an ejecta plume is evidenced by accretionary lapilli in the Nördlingen 1973 core. In summary, allochthonous impactites at the Ries impact structure are not unusual but are consistent with observations from other terrestrial and planetary craters, where melt-rich impactites overly ballistic ejecta deposits both outside and inside crater rims and where melt-rich impactites occur in crater interiors.</p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 10","pages":"2622-2650"},"PeriodicalIF":2.2,"publicationDate":"2024-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/maps.14241","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141832263","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"2021 Nier Prize for Dr. Nan Liu","authors":"Larry R. Nittler","doi":"10.1111/maps.14237","DOIUrl":"10.1111/maps.14237","url":null,"abstract":"","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 S1","pages":"A491-A492"},"PeriodicalIF":2.2,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogy of the Martian mantle inferred from bulk chemical compositions","authors":"Shuying Yang,&nbsp;Munir Humayun,&nbsp;Kevin Righter","doi":"10.1111/maps.14235","DOIUrl":"10.1111/maps.14235","url":null,"abstract":"<p>Understanding the mineralogy of the Martian mantle is essential for constructing geochemical and geophysical models of Mars. This study employs the pMELTS program to determine the mineralogy at the solidus from 11 published bulk silicate Mars (BSM) compositions, within a pressure range of 2–5 GPa. The pMELTS results align with experimental data and calculations from another thermodynamic program (Perple_X/stx11). Mineral modes from compositional models based on Martian meteorite geochemistry show relatively consistent abundances modes (olivine: 48–56 wt%, orthopyroxene: 20–25 wt%, clinopyroxene: 15–17 wt%, garnet: 6–9 wt%). In contrast, mineral modes from compositional models that are not based on Martian meteorite geochemistry exhibit a wider range of olivine and garnet abundances. Additionally, we constrained the mineral modes of the Martian mantle using trace element partitioning and partial melting models. Our calculations indicate that melts derived from mantle sources with a hypothesized garnet content of 5–10 wt% closely match the analyzed compositions of shergottites, validating the garnet mode (6–9 wt%) constrained in our pMELTS calculations. Extracting low-degree (&lt;4 wt%) melts from a BSM to form depleted Martian mantle (DMM) does not significantly alter the mineralogical modes of solid residues, but it does lead to substantial trace elemental depletion in the DMM. Therefore, enriched, intermediate, and depleted shergottite sources are likely characterized by similar mineral modes yet differ in incompatible element abundances.</p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 9","pages":"2545-2564"},"PeriodicalIF":2.2,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141654037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Award of the 2007 Nier Prize to Thorsten Kleine","authors":"Klaus Mezger","doi":"10.1111/maps.14243","DOIUrl":"10.1111/maps.14243","url":null,"abstract":"","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 S1","pages":"A493-A494"},"PeriodicalIF":2.2,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141653359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corundum ± magnesium-deltalumite ± hibonite-bearing objects in the CH chondrite Sayh al Uhaymir 290","authors":"Konstantin M. Ryazantsev,&nbsp;Alexander N. Krot,&nbsp;Chi Ma,&nbsp;Marina A. Ivanova,&nbsp;Cyril A. Lorenz,&nbsp;Vasiliy D. Shcherbakov","doi":"10.1111/maps.14238","DOIUrl":"10.1111/maps.14238","url":null,"abstract":"<p>Isolated corundum grains and corundum ± Mg-deltalumite [(Al,Mg)(Al,◻)₂O₄] ± hibonite assemblages were investigated in the CH3.0 metal-rich carbonaceous chondrite Sayh al Uhaymir (SaU) 290. Although very refractory inclusions containing abundant Zr- and Sc-rich oxides and silicates, hibonite, grossite, or perovskite have been previously described in CH chondrites, this is the first discovery of corundum and Mg-deltalumite in CHs and the first discovery of Mg-deltalumite in nature. Magnesium-deltalumite can be indexed by the <i>Fd</i>3<i>m</i> spinel-type structure and gives a perfect fit to the synthetic Al-rich spinel cells. Corundum-Mg-deltalumite grains, 5–20 μm in size, are occasionally rimmed by a thin layer of hibonite replacing corundum. Some corundum grains contain tiny inclusions of ultrarefractory Zr,Sc-rich minerals and platinum-group element (PGE) nuggets. All corundum, hibonite, and Mg-deltalumite grains studied have ¹⁶O-rich compositions (average Δ¹⁷O ± 2SD = −22 ± 3‰). Two corundum grains show evidence for significant mass-dependent fractionation of oxygen isotopes: Δ¹⁸O ~ +34‰ and ~ +19‰. We suggest that the SaU 290 corundum-rich objects were formed by evaporation and/or condensation in a hot nebular region close to the proto-sun where the ambient temperature was close to the condensation temperature of corundum. A corundum grain with tiny inclusions of Zr- and Sc-rich phases and PGE metal nuggets recorded formation temperatures higher than the condensation temperature of corundum. Two corundum-rich objects with highly fractionated oxygen isotopes must have crystallized from a melt that experienced evaporation. Corundum grains corroded by hibonite recorded gas–solid interaction in this region during its cooling. The Mg-deltalumite ± corundum ± hibonite objects were formed by rapid crystallization of high-temperature (&gt;2000°C) refractory melts. The lack of minerals with condensation temperatures below those of corundum and hibonite in the SaU 290 corundum-rich objects suggests that after formation, these objects were rapidly removed from the hot nebular region by disk wind and/or by turbulent diffusion and disk spreading.</p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 10","pages":"2608-2621"},"PeriodicalIF":2.2,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141665056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cover","authors":"","doi":"10.1111/maps.14014","DOIUrl":"https://doi.org/10.1111/maps.14014","url":null,"abstract":"<p>\u0000 \u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure>\u0000 </p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 7","pages":"i"},"PeriodicalIF":2.2,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/maps.14014","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141583982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shock-induced pervasive remelting of Fe sulfides in the basaltic shergottite Northwest Africa 14672: A benchmark for shock stages S6/S7 on Mars","authors":"Jean-Pierre Lorand,&nbsp;Sylvain Pont,&nbsp;Roger H. Hewins,&nbsp;Brigitte Zanda","doi":"10.1111/maps.14233","DOIUrl":"10.1111/maps.14233","url":null,"abstract":"<p>Northwest Africa (NWA) 14672, the most highly shocked Martian meteorite so far, has experienced &gt;50% melting, compatible with peak pressure &gt;~65 Gpa, at a transition stage 6/7. Despite these extreme shock conditions, the meteorite still preserves a population of “large” Fe sulfide blebs from the pre-shock igneous assemblage. These primary blebs preserve characteristics of basaltic shergottites in term of modal abundance, preferential occurrence in interstitial pores along with late-crystallized phases (ilmenite, merrillite), and Ni-free pyrrhotite compositions. Primary sulfides underwent widespread shock-induced remelting, as indicated by perfect spherical morphologies when embedded in fine-grained silicate melt zones and a wealth of mineral/glass/vesicle inclusions. Extensive melting of Fe-sulfides is consistent with the decompression path experienced by NWA 14672 after the peak shock pressure at ~70 GPa. Primary sulfides acted as preferential sites for nucleation of vesicles of all sizes which helped sulfur degassing during decompression, leading to partial resorption of Fe-sulfide blebs and reequilibration of pyrrhotite metal/sulfur ratios (0.96–0.98) toward the low oxygen fugacity conditions indicated by Fe-Ti oxides hosted in fine-grained materials. The extreme shock intensity also provided suitable conditions for widespread in situ redistribution of igneous sulfur as micrometric globules concentrated in glassy portions of fine-grained lithologies. These globules exsolved early on quenching, allowing dendritic skeletal Fe-Ti oxide overgrowths to nucleate on sulfides.</p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 9","pages":"2523-2544"},"PeriodicalIF":2.2,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141677572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Raman spectroscopy of Ryugu particles and their extracted residues: Fluorescence background characteristics and similarities to CI chondrites","authors":"Mutsumi Komatsu,&nbsp;Hikaru Yabuta,&nbsp;Yoko Kebukawa,&nbsp;Lydie Bonal,&nbsp;Eric Quirico,&nbsp;Timothy J. Fagan,&nbsp;George D. Cody,&nbsp;Jens Barosch,&nbsp;Laure Bejach,&nbsp;Emmanuel Dartois,&nbsp;Alexandre Dazzi,&nbsp;Bradley De Gregorio,&nbsp;Ariane Deniset-Besseau,&nbsp;Jean Duprat,&nbsp;Cecile Engrand,&nbsp;Minako Hashiguchi,&nbsp;Zita Martins,&nbsp;Jérémie Mathurin,&nbsp;Gilles Montagnac,&nbsp;Smail Mostefaoui,&nbsp;Larry R. Nittler,&nbsp;Takuji Ohigashi,&nbsp;Taiga Okumura,&nbsp;Laurent Rémusat,&nbsp;Scott Sandford,&nbsp;Rhonda Stroud,&nbsp;Hiroki Suga,&nbsp;Yoshio Takahashi,&nbsp;Yasuo Takeichi,&nbsp;Yusuke Tamenori,&nbsp;Maximilien Verdier-Paoletti,&nbsp;Shohei Yamashita,&nbsp;Hisayoshi Yurimoto,&nbsp;Tomoki Nakamura,&nbsp;Takaaki Noguchi,&nbsp;Ryuji Okazaki,&nbsp;Hiroshi Naraoka,&nbsp;Kanako Sakamoto,&nbsp;Makoto Yoshikawa,&nbsp;Takanao Saiki,&nbsp;Satoshi Tanaka,&nbsp;Fuyuto Terui,&nbsp;Satoru Nakazawa,&nbsp;Tomohiro Usui,&nbsp;Masanao Abe,&nbsp;Tatsuaki Okada,&nbsp;Toru Yada,&nbsp;Masahiro Nishimura,&nbsp;Aiko Nakato,&nbsp;Akiko Miyazaki,&nbsp;Kasumi Yogata,&nbsp;Shogo Tachibana,&nbsp;Sei-ichiro Watanabe,&nbsp;Yuichi Tsuda","doi":"10.1111/maps.14234","DOIUrl":"10.1111/maps.14234","url":null,"abstract":"<p>We present here an investigation of Ryugu particles recovered by the Hayabusa2 space mission and their extracted carbonaceous acid residues using Raman spectroscopy. Raman parameters of Ryugu intact grains and their acid residues are characterized by broad D (defect induced) and G (graphite) band widths, indicating the presence of polyaromatic carbonaceous matter with low thermal maturity. Raman spectra of Ryugu particles and CI (type 1) chondrites exhibit stronger laser-induced fluorescence backgrounds compared to Type 2 and Type 3 carbonaceous chondrites. The high fluorescence signatures and wide bandwidths of the D and G bands of Ryugu intact grains are similar to the Raman spectra observed in CI chondrites, reflecting the low structural order of their aromatic carbonaceous matter, and strengthening the link between Ryugu particles and CI chondrites. The high fluorescence background intensity of the Ryugu particles is due to multiple causes, but it is likely that the relative abundance of geometry-bearing macromolecular organic matter in total organic carbon contents makes a large contribution to the fluorescence intensities. Locally observed high fluorescence in the acid-extracted residues of Ryugu is due to nitrogen-bearing outlier phase. The high fluorescence signature is one consequence of the low degree of thermal maturity of the organic matter and supports evidence that the Ryugu particles have escaped significant parent body thermal metamorphism.</p>","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 8","pages":"2166-2185"},"PeriodicalIF":2.2,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141679716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Award of the 2024 Barringer Medal to Dr. John Spray","authors":"Michael R. Dence","doi":"10.1111/maps.14232","DOIUrl":"10.1111/maps.14232","url":null,"abstract":"","PeriodicalId":18555,"journal":{"name":"Meteoritics & Planetary Science","volume":"59 S1","pages":"A489-A490"},"PeriodicalIF":2.2,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141684784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}