Modeling the evolution of the parent body of acapulcoites and lodranites

• Verfasst von: Neumann, Wladimir [VerfasserIn]
• Verfasst von: Henke, Stephan-Markus [VerfasserIn]
• Verfasst von: Gail, Hans-Peter [VerfasserIn]
• Verfasst von: Schwarz, Winfried H. [VerfasserIn]
• Verfasst von: Trieloff, Mario [VerfasserIn]
• Verfasst von: Hopp, Jens [VerfasserIn]
• Titel: Modeling the evolution of the parent body of acapulcoites and lodranites
• Titelzusatz: a case study for partially differentiated asteroids
• Verf.angabe: Wladimir Neumann, Stephan Henke, Doris Breuer, Hans-Peter Gail, Winfried H. Schwarz, Mario Trieloff, Jens Hopp, Tilman Spohn
• E-Jahr: 2018
• Jahr: 30 March 2018
• Umfang: 24 S.
• Fussnoten: Gesehen am 29.08.2019
• Titel Quelle: Enthalten in: Icarus
• Ort Quelle: Orlando, Fla. : Academ. Press, 1962
• Jahr Quelle: 2018
• Band/Heft Quelle: 311(2018), Seite 146-169
• ISSN Quelle: 0019-1035
• DOI: doi:10.1016/j.icarus.2018.03.024
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Accretion
• Sach-SW: Asteroids
• Sach-SW: Composition
• Sach-SW: Interiors
• Sach-SW: Meteorites
• Sach-SW: Planetesimals
• Sach-SW: Thermal histories
• K10plus-PPN: 1672407117

Abstract

The acapulcoites and lodranites are rare groups of primitive achondrites that originate from a common parent body and are of particular interest since they experienced only partial melting. We calculated thermal evolution and differentiation models of the parent body of the Acapulco-Lodran meteorite clan. The models were compared to the maximum metamorphic temperatures, differentiation degree, and thermo-chronological data available. An optimized set of parameters which fits to the data was determined: A radius of≈260km, a formation time of≈1.7 Ma after CAIs and an initial temperature of≈250K. The burial depths derived are 7-13km. The respective layers experienced minor melting and small-scale melt migration, matching the differentiation degree of the meteorites. The resulting structure has an iron core, a silicate mantle, a partially differentiated layer, and an undifferentiated outer shell. Our results indicate a larger size, an earlier formation time, and a formation closer to the sun of the parent body of acapulcoites and lodranites than typical estimates for ordinary chondritic parent bodies, consistent with a stronger thermal metamorphism. The burial depths support excavation by a single impact. The presence of core and mantle indicates that these meteorites could share a common parent body with differentiated stony and iron meteorites.