TY - JOUR
T1 - A mineralogical and geochemical study of polymict eucrite discovered in Sahara of southwest Algeria
AU - Seddiki, Abdelmadjid
AU - Moine, Bertrand
AU - Cottin, Jean Yves
AU - Bascou, Jérôme
AU - Godard, Marguerite
AU - Faure, François
AU - Bourot-Denise, Michèle
AU - Remaci, Nacera
PY - 2013
Y1 - 2013
N2 - NWA2268 is a polymict eucrite discovered in the Sahara, at southwest Algeria, close to the region of Tindouf. This meteorite weighs 65 g and presents a thin black fusion crust. The rock is fine- to medium-grained breccia and contains mineral fragments of plagioclases, pyroxenes, spinel, olivine and silica. The rock contains some basaltic fragments with sub-ophitic or cumulative textures, constituted by plagioclases and exsolved pigeonite. Pyroxferroite grains are present and locally destabilised in an association of hedenbergite, fayalite and silica. It also presents unequilibrated eucritic clast with heterogeneous pyroxenes and plagioclases compositions. Pyroxenes in the all of the other clasts have equilibrated composition, with exolved pigeonites with augite lamellaes. This polymict eucrite contains also partially devitrified glass that represents impact melts linked to impact event. None recrystallization of this glass confirms a lack of post-brecciation metamorphism. Diogenitic fragments are less abundant than 10 %. The oxygen isotopic composition of NWA2268 is Δ17O (-0.43). This meteorite is interpreted as belonging to the HED group attributed to the 4-Vesta asteroid.
AB - NWA2268 is a polymict eucrite discovered in the Sahara, at southwest Algeria, close to the region of Tindouf. This meteorite weighs 65 g and presents a thin black fusion crust. The rock is fine- to medium-grained breccia and contains mineral fragments of plagioclases, pyroxenes, spinel, olivine and silica. The rock contains some basaltic fragments with sub-ophitic or cumulative textures, constituted by plagioclases and exsolved pigeonite. Pyroxferroite grains are present and locally destabilised in an association of hedenbergite, fayalite and silica. It also presents unequilibrated eucritic clast with heterogeneous pyroxenes and plagioclases compositions. Pyroxenes in the all of the other clasts have equilibrated composition, with exolved pigeonites with augite lamellaes. This polymict eucrite contains also partially devitrified glass that represents impact melts linked to impact event. None recrystallization of this glass confirms a lack of post-brecciation metamorphism. Diogenitic fragments are less abundant than 10 %. The oxygen isotopic composition of NWA2268 is Δ17O (-0.43). This meteorite is interpreted as belonging to the HED group attributed to the 4-Vesta asteroid.
KW - 4-Vesta
KW - Algeria
KW - Basaltic achondrite
KW - Meteorite
KW - NWA2268
KW - Polymict eucrite
UR - http://www.scopus.com/inward/record.url?scp=84940297281&partnerID=8YFLogxK
U2 - 10.1007/s12517-012-0624-4
DO - 10.1007/s12517-012-0624-4
M3 - Article
AN - SCOPUS:84940297281
VL - 6
SP - 3175
EP - 3184
JO - Arabian Journal of Geosciences
JF - Arabian Journal of Geosciences
SN - 1866-7511
IS - 9
ER -