The Open UniversitySkip to content
 

Petrology, geochemistry, and cosmic-ray exposure age of lherzolitic shergottite Northwest Africa 1950

Gillet, P.; Barrat, J. A.; Beck, P.; Marty, B.; Greenwood, R.; Franchi, I.; Bohn, M. and Cotten, J. (2005). Petrology, geochemistry, and cosmic-ray exposure age of lherzolitic shergottite Northwest Africa 1950. Meteoritics and Planetary Science, 40(8) pp. 1175–1184.

URL: http://www.ingentaconnect.com/content/arizona/maps...
Google Scholar: Look up in Google Scholar

Abstract

Northwest Africa (NWA) 1950 is a new member of the lherzolitic shergottite clan of the Martian meteorites recently found in the Atlas Mountains. The petrological, mineralogical, and geochemical data are very close to those of the other known lherzolitic shergottites. The meteorite has a cumulate gabbroic texture and its mineralogy consists of olivine (Fo66 to Fo75), low and high-Ca pyroxenes (En78Fs19Wo2-En60Fs26W14; En53Fs16Wo31-En45Fs14Wo41), and plagioclase (An57Ab41Or1 to An40Ab57Or3; entirely converted into maskelynite during intense shock metamorphism). Accessory minerals include phosphates (merrillite), chromite and spinels, sulfides, and a glass rich in potassium. The oxygen isotopic values lie on the fractional line defined by the other SNC meteorites (Δ17O = 0.312 ‰). The composition of NWA 1950 is very similar to the other lherzolitic shergottites and suggests an origin from the same magmatic system, or at least crystallization from a close parental melt. Cosmogenic ages indicate an ejection age similar to those of the other lherzolitic shergottites. The intensity of the shock is similar to that observed in other shergottites, as shown by the occurrence of small melt pockets containing glass interwoven with stishovite.

Item Type: Journal Item
ISSN: 1086-9379
Academic Unit/School: Faculty of Science, Technology, Engineering and Mathematics (STEM) > Physical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM)
Item ID: 7990
Depositing User: Kyra Proctor
Date Deposited: 12 Jun 2007
Last Modified: 01 May 2019 13:16
URI: http://oro.open.ac.uk/id/eprint/7990
Share this page:

Actions (login may be required)

Policies | Disclaimer

© The Open University   contact the OU