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The Meteoritical Bulletin, No. 99, April 2012*

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The Meteoritical Bulletin, No. 99, April 2012* The Meteoritical Bulletin, No. 99, April 2012* Laurence A.J. GARVIE Center for Meteorite Studies, Arizona State University, Tempe, Arizona 85287-1404, USA. Abstract – This issue of the Meteoritical Bulletin reports on 1075 meteorites divided between 468 non-Antarctic and 607 Antarctic meteorites. Written descriptions are given for eight falls (Fuhe, Kemer, Lorton, Mason Gully, Mifflin, Red Canyon Lake, Varre-Sai, and Whetstone Mountains). Particularly notable are descriptions and chemical data for 42 new iron meteorites, many of which are unpaired. Also reported are seven Martian meteorites totaling 1447.1 g (four non-Antarctic) and 14 lunar meteorites totaling 9451 g (10 non-Antarctic). Other noteworthy meteorites include NWA 5958, a C3.0-ung with an extremely 16O-rich bulk oxygen isotopic composition; Sayh al Uhaymir 493, an ungrouped achondrite with significant ferric iron, and Northwest Africa 6704, an unusual ungrouped achondrite characterized by relatively ferroan mafic silicate minerals with oxygen isotopic composition that plots within the field for acapulcoites-lodranites. Also reported are two new dense collection areas: Biduna Blowhole in Australia and Stump Spring in the United States. Antarctic meteorites reported include those recovered by the ANSMET (US) and NIPR (Japan) meteorite recovery programs. *Prepared by the Nomenclature Committee of the Meteoritical Society under the Editorship of L. Garvie. Members for 2011 are M Grady, R Greenwood, J Grossman (Database editor), H Haack, C Herd (Chair), W Hsu, T Mikouchi, S Mostefaoui, S Murty, P Rochette, A Ruzicka, C Smith (Secretary), M Weisberg, K Welten, L Welzenbach. Further information can be found at http://meteoriticalsociety.org/bulletin/TermExpirations2012.htm E1 INTRODUCTION composition for the olivine (Fa23-25 average 24, sd=1) than for the The Meteoritical Bulletin is the announcement for meteorite pyroxene (average Fs19, sd=4). names and classifications that have been reviewed and approved by the Classification: Ordinary chondrite (L4) Meteoritical Society’s Meteorite Nomenclature Committee. Guidelines Specimens: A sample of 157.2 g from the first stone, a PTS and a thick for meteorite nomenclature as well as information on submitting a PS are on deposit at the MNHNP. Mr Kasikçi holds the main mass. The meteorite for review can be found on the society’s webpage second (1.7 kg) and the third (1.5 kg) stones are kept by Prof. Özel now (http://meteoriticalsociety.org/). Additional information on meteorites at CagU. reported in tables can be found in the Meteorite Bulletin Database, which can be accessed from the society website. Lorton 38.70066°N, 77.21163°W Virginia, United States Fell: 18 Jan 2010, 5:45 PM EST (UT-5) FALLS Classification: Ordinary chondrite (L6) History: People in the greater Washington DC area (with reports from Fuhe 31°28’32"N, 113°34’01"E as far away as West Virginia) describe seeing a large, single, fireball Suizhou City, Hubei Province, China near dusk on Monday, January 18th, 2010 (~5:45 pm). Some describe Fell: June 1945 hearing a large detonation. One stone fell through the roof and ceiling Classification: Ordinary chondrite (L5) of the Williamsburg Square Family Practice in Lorton, Virginia. The History: In June 1945, a stone fell into the backyard of Mr. Chen, who meteorite was found embedded in the concrete floor (under the carpet), lived in Dongjiagang village, Fuhe town, Suizhou city, Hubei province, apparently having broken into three large pieces and a number of China. The stone was left in the yard for many years and later mounted smaller pieces upon impact. The doctors were present at the time the on a wall. The grandson of the finder noticed the unusual character of meteorite fell, and describe hearing a sound akin to bookshelves the stone and brought it to China University of Geosciences at Wuhan crashing to the ground. The meteorite was taken to the Smithsonian for identification in April 2010. Institution for identification. Physical characteristics: Total mass of the stone is 23 kg. Most fusion Physical characteristics: The meteorite is approximately 8 x 5 x 5 cm, crust has been weathered, but a few black patches remain. The outer 2 roughly rectangular, with dark, matte fusion crust. The interior is fresh, to 3 cm of the stone is weathered, as seen in cross section. with no evidence of oxidation of the metal grains, which are small and Petrography: Well-defined chondrules range in size from 400 to 1200 evenly distributed throughout the rock. A few small poorly defined µm with barred olivine chondrules being most abundant. Shock veins chondrules are visible with the naked eye. The total mass recovered is are visible in hand specimen. There are several clasts of chromite 329.7 g. fragments set in plagioclase groundmass. Petrography: Shock stage: S1 (olivines have irregular fractures). Geochemistry: Xiao Long (CUG) EMP: Olivine Fa ; pyroxene 24.20±0.26 Weathering grade: W0. Shock veins absent. Chondrules are rare. When Fs Wo . 22.12±0.98 1.49±0.23 present, chondrule outlines are diffuse and show some degree of Classification: Ordinary chondrite (L5) recrystallization, with many crystals exhibiting 120° triple junctions. Specimens: A mass of 2.3 kg is on deposit at CUG. Mr. Jun Chen holds Metal and sulfide occur mostly as separate, blocky grains. the main mass. Geochemistry: (C. Corrigan, SI) Olivine, Fa24.7±0.3 (n=23), pyroxene Fs20.9±0.3Wo1.6±0.2 (n=16), feldspar An10.3±0.3Or6.4±2.8 (n=14) Kemer 36°32'31"N, 29°25'05.6"E Classification: L6 chondrite Mugla, Turkey Specimens: Entire mass is at SI. Fell: March 3, 2008 Classification: Ordinary chondrite (L4) Mason Gully [coordinates temporarily withheld] History: Sonic booms were heard between 11 am and noon local time Western Australia, Australia south of Kemer Town, Fethiye County, Mugla. A young woman, Mrs Fell: 13 April 2010 at 10h36m10s UTC Rabia Saadet, was hanging out her washing when she was startled by a Classification: Ordinary chondrite (H5) loud booming sound. A stone fell about 50 m away in her wheat field History: A bright fireball was recorded over southwestern Australia by by her house. Panicked, she hid in her home. Later she went back to the observatories of the Desert Fireball Network. A fall position was field and discovered a black stone buried about 25 cm. Her father called pinpointed by triangulation (Pavel Spurny, CzAS), and a search was the village chief, "muhtar", who called the local police. Another rock mounted (Martin Towner, ICL). A stone was recovered 3rd November was found 500 m away and both were taken to Fethiye Governor’s 2010, within 150 m of the predicted fall site. Office. Mesut Kasikci, a meteorite hunter living in France called the Physical characteristics: (Gretchen Benedix, NHM; Philip Bland, muhtar and informed Prof. Mehmet Emin Özel, an astrophysicist at Kathryn Dyl, Martin Towner, ICL). An ~3 cm, 50% fusion crusted, CanaU, Physics Department, of the fall. Prof. Özel and Tamer Akin, his 24.54 g stone was recovered. Individual pyroxene, olivine, and feldspar assistant, went to Fethiye and acquired the stones from the Governor. A crystals are visible on the broken surface, with no evidence of alteration third piece was found ten days later. of silicates. Some rust patches visible around metal grains on original Physical characteristics: Three fusion crusted stones were found: broken surfaces. Although the meteorite appears to have high porosity Stone 1, 4×11×7.5 cm, 2.56 kg; Stone 2, 1.7 kg, 36°32'39.9"N, (based on observations of sawn surfaces), metal in the interior shows no 29°24'49.9"E; and Stone 3, 1.5 kg - 36°32'35.4"N 29°24'20"E). sign of alteration. Fusion crust is black and fresh. Petrography: Matrix poor, chondrule rich. Chondrules of variable sizes Petrography: (Gretchen Benedix, NHM). The meteorite has a typical and textures, some slightly deformed. Occurrence of rare relict olivines, petrologic type 5 texture, with discernible, but not distinct chondrules. chromites, two phosphates: chlorapatite and whitlockite up to 300 µm. Chondrule types include BO and RP. Minerals are heterogeneously An idiomorphic Zr oxide was observed in an ilmenite crystal from a distributed. Modal mineralogy (in vol%) is: olivine 33; orthopyroxene chondrule. Amoeboid objects containing diopside, chromite and 38; clinopyroxene 5; plagioclase 8; metal 11; sulfide 5; minor feldspar. Polycrystalline sulfides, healed faults and maskelynite. components around 1. Geochemistry: EMPA of crystals indicate a more homogeneous Geochemistry: (Gretchen Benedix, NHM; Richard Greenwood, Ian E2 Franchi, Jenny Gibson, OU). Mineral compositions as determined by percentages determined from one thin section show 5.5% metal, 2.0% EMP: olivine, Fa19.2±0.6; low-Ca pyroxene, Fs16.±0.4Wo1.4±0.3; chromite troilite, and 0.01% chromite. Contains a rare unidentified Fe-Cr sulfide. 17 (Fe/Fe+Mg=0.84; Cr/Cr+Al=0.86). Oxygen isotopes: δ O=3.04‰, Geochemistry: (Laurence Garvie, ASU) Olivine - Fa19.40 (range 19.23 to 18 17 δ O=4.42‰, and Δ O=0.74‰. 19.58, n=9); Pyroxene - Fs16.74 (range 16.54 to 16.89) and Wo1.11 (range Classification: Ordinary chondrite (H5), S1, minimal weathering. 0.76 to 1.30). Specimens: The stone and one thin section are on deposit at WAM. Classification: Ordinary chondrite (H5), shock stage S1 Specimens: ASU holds 4.24 g distributed between a complete slice, two Mifflin 42°54’27"N, 90°21’56"W thin sections and an end piece in a potted butt. Iowa County, Wisconsin, United States Fell: April 14, 2010, 10:07 pm CDT (UT-5) Varre-Sai 20°51.041’S, 41°44.808’W Classification: Ordinary chondrite (L5) Rio de Janeiro, Brazil History: A bright fireball was seen by numerous observers in parts of Fell: 19 June 2010, 21:00 UT Wisconsin, Iowa, and Illinois the night of April 14th, 2010.
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