|Northwest Africa 2986|
|Basic information||Name: Northwest Africa 2986|
This is an OFFICIAL meteorite name.
Abbreviation: NWA 2986
Observed fall: No
Year found: 2006
Mass: 201 g
This is 1 of 153 approved meteorites (plus 1 unapproved name) classified as Martian (shergottite). [show all]
Search for other: Martian meteorites
|Comments:||Approved 19 May 2010|
Writeup from MB 98:
Northwest Africa 2986 (NWA 2986)
Classification: Martian meteorite (shergottite)
History: Three partially crusted stones with a weight of 201 g were purchased in Erfoud, Morocco, in 2006.
Petrography: (T. Bunch and J. Wittke, NAU): A basaltic shergottite that contains 54 vol% Ca-pyroxene (pigeonite and augite), 41 vol% plagioclase (maskelynite) and minor ulvöspinel, ilmenite, merrillite, chlorapatite, pyrrhotite, and K-Si-rich, late stage glasses. Pyroxene shows mottled compositional zoning. Dark, shock pocket glasses and veins are also present. A few melt inclusions of K-Si-rich glass, phosphates, ferroan pigeonite, and ilmenite were found in ulvöspinel.
Geochemistry: Pigeonite Fs37.4-53.8Wo10.8-15.8 (FeO/MnO = 34); augite Fs27.8-40.6Wo33.4-36.0; maskelynite An54.7Or1.6. Oxygen isotopes (D. Rumble, CIW): Replicate analyses of acid-washed whole rock samples by laser fluorination gave, respectively δ18O = 4.65, 4.59, 4.45, 4.78, δ17O = 2.73, 2.67, 2.58, 2.80, Δ17O = 0.280, 0.260, 0.240, 0.284 (all permil). Bulk composition (ICPMS, C. Herd, UAb): (mean of 2 replicate analyses, in ppm) La 0.97, Ce 2.32, Nd 1.70, Sm 0.71, Eu 0.43, Gd 1.71, Dy 1.12, Yb 0.85, Lu 0.12, Hf 1.07, Ba 21, Cr 646, V 236, Ni 47, Co 29.
Classification: Martian (shergottite) with an "enriched" chondrite-normalized rare earth element pattern, and probably paired with NWA 2975 and related stones. Low weathering grade and a moderate shock level.
Specimens: 21.3 g is on deposit at NAU. MFarmer and Strope are the main mass holders.
NAU: Geology, Bldg 12
Northern Arizona University, Flagstaff, AZ 86011, United States; Website (institutional address; updated 12 Apr 2012)
UAb: 1-26 Earth Sciences Building, University of Alberta, Edmonton, AB, T6G 2E3, Canada, Canada; Website (institutional address; updated 17 Oct 2011)
CIW: Carnegie Insitution Washington, Geophysical Laboratory, 5251 Broad Branch Rd., NW, Washington DC 20015, United States (institutional address)
MFarmer: Michael Farmer, P.O. Box 86059, Tucson, AZ 85754-6059, United States; Website (private address)
Strope: 421 Fourth Street, Glen Dale, WV 26038, United States; Website (private address)
|References:||Published in Meteoritical Bulletin, no. 98, MAPS 45, 1530-1551 (2010)|
This is 1 of 1212 approved meteorites from Morocco (plus 11 unapproved names)
Direct link to this page