Buchumschlag

Sierra Gorda 009: a new member of the metal-rich G chondrites grouplet

We investigated the metal-rich chondrite Sierra Gorda (SG) 009, a member of the new G chondrite grouplet (also including NWA 5492, GRO 95551). G chondrites contain 23% metal, very reduced silicates, and rare oxidized mineral phases (Mg-chromite, FeO-rich pyroxene). G chondrites are not related to CH...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Ivanova, Marina A. (VerfasserIn) , Lorenz, Cyril A. (VerfasserIn) , Humayun, Munir (VerfasserIn) , Corrigan, Catherine M. (VerfasserIn) , Ludwig, Thomas (VerfasserIn) , Trieloff, Mario (VerfasserIn) , Righter, Kevin (VerfasserIn) , Franchi, Ian A. (VerfasserIn) , Verchovsky, Alexander B. (VerfasserIn) , Korochantseva, Ekaterina V. (VerfasserIn) , Kozlov, Vladimir V. (VerfasserIn) , Teplyakova, Svetlana N. (VerfasserIn) , Korochantsev, Alexander V. (VerfasserIn) , Grokhovsky, Victor I. (VerfasserIn)
Dokumenttyp: Article (Journal)
Sprache:Englisch
Veröffentlicht: 03 August 2020
In: Meteoritics & planetary science
Year: 2020, Jahrgang: 55, Heft: 8, Pages: 1764-1792
ISSN:1945-5100
DOI:10.1111/maps.13546
Online-Zugang:Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1111/maps.13546
Verlag, lizenzpflichtig, Volltext: https://onlinelibrary.wiley.com/doi/abs/10.1111/maps.13546
Volltext
Verfasserangaben:Marina A. Ivanova, Cyril A. Lorenz, Munir Humayun, Catherine M. Corrigan, Thomas Ludwig, Mario Trieloff, Kevin Righter, Ian A. Franchi, Alexander B. Verchovsky, Ekaterina V. Korochantseva, Vladimir V. Kozlov, Svetlana N. Teplyakova, Alexander V. Korochantsev, and Victor I. Grokhovsky
Beschreibung
Zusammenfassung:We investigated the metal-rich chondrite Sierra Gorda (SG) 009, a member of the new G chondrite grouplet (also including NWA 5492, GRO 95551). G chondrites contain 23% metal, very reduced silicates, and rare oxidized mineral phases (Mg-chromite, FeO-rich pyroxene). G chondrites are not related to CH-CB chondrites, based on bulk O, C, and N isotopic compositions, mineralogy, and geochemistry. G chondrites have no fine-grained matrix or matrix lumps enclosing hydrated material typical for CH-CB chondrites. G chondrites’ average metal compositions are similar to H chondrites. Siderophile and lithophile geochemistry indicates sulfidization and fractionation of the SG 009 metal and silicates, unlike NWA 5492 and GRO 95551. The G chondrites have average O isotopic compositions Δ17O>0‰ ranging between bulk enstatite (E) and ordinary (O) chondrites. An Al-rich chondrule from SG 009 has Δ17O>0‰ indicating some heterogeneity in oxygen isotopic composition of G chondrite components. SG 009’s bulk carbon and nitrogen isotopic compositions correspond to E and O chondrites. Neon isotopic composition reflects a mixture of cosmogenic and solar components, and cosmic ray exposure age of SG 009 is typical for O, E, and R chondrites. G chondrites are closely related to O, E, and R chondrites and may represent a unique metal-rich parent asteroid containing primitive and fractionated material from the inner solar system. Oxidizing and reducing conditions during SG 009 formation may be connected with a chemical microenvironment and possibly could indicate that G chondrites may have formed by a planetesimal collision resulting in the lack of matrix.
Beschreibung:Gesehen am 30.06.2021
Beschreibung:Online Resource
ISSN:1945-5100
DOI:10.1111/maps.13546

Ähnliche Einträge