The Meteoritical Bulletin, No. 100, 2014 June 1,* 2 3 Alex RUZICKA , Jeffrey N
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The Meteoritical Bulletin, No. 100, 2014 June 1,* 2 3 Alex RUZICKA , Jeffrey N. GROSSMAN and Laurence GARVIE 1Cascadia Meteorite Laboratory, Portland State University, Portland, Oregon, 97207-0751, USA 2U.S. Geological Survey, MS 954, Reston, Virginia 20192, USA 3Center for Meteorite Studies, Arizona State University, Tempe, Arizona, 85287-1404 *Corresponding author's e-mail address: [email protected] Abstract− Meteoritical Bulletin 100 contains 1943 meteorites including 8 falls (Boumdeid (2011), Huaxi, Košice, Silistra, Sołtmany, Sutter's Mill, Thika, Tissint), with 1575 Ordinary chondrites, 139 Carbonaceous chondrites, 96 HED achondrites, 25 Ureilites, 18 Primitive achondrites, 17 Iron meteorites, 15 Enstatite chondrites, 11 Lunar meteorites, 10 Mesosiderites, 10 Ungrouped achondrites, 8 Pallasites, 8 Martian meteorites, 6 Rumuruti chondrites, 3 Enstatite achondrites, and 2 Angrites, and with 937 from Antarctica, 592 from Africa, 230 from Asia, 95 from South America, 44 from North America, 36 from Oceania, 6 from Europe, and 1 from an unknown location. This will be the last Bulletin published in the current format. Information about approved meteorites can be obtained from the Meteoritical Bulletin Database (MBD) available on line at http://www.lpi.usra.edu/meteor/ . E1 Meteoritics & Planetary Science 49, E1–E101 (2014) © Meteoritical Society, 2014. Printed in USA. Acfer 394 27°31.12’N, 3°52.82’E Petrography: Chondrules are up to 1.4 mm in diameter. There are Tamanghasset, Algeria coarse metal grains in matrix and decorating chondrule surfaces. Found: Oct 2001 The metal grains are up to 750 µm in maximum dimension. Likely Classification: Carbonaceous chondrite (CR2) paired with Acfer 394-400. Petrography: Chondrules to 3 mm. Coarse metal grains in the matrix and decorating chondrule surfaces. Metal grains to 500 μm. Ackerly 32°35.42’N, 101°46.33’W Likely paired with Acfer 395, 396, and 397. Other CR chondrites Dawson County, Texas, United States from Acfer have been found in the same area and may also be Found: June 1995 paired with these samples. Classification: Ordinary chondrite (L5) History: Mr. Grigg found this sample while he was plowing a Acfer 395 27°30.55’N, 3°53.26’E cotton field. Tamanghasset, Algeria Specimens: 291 g, one thick section, and one thin section are on Found: Oct 2001 deposit at TCU. 225 g sample held at TxTech. Classification: Carbonaceous chondrite (CR2) Petrography: Section contains porphyritic and barred olivine Apache Junction 33°27’N, 111°31’W chondrules with an average size of 850 μm. There are large metal Arizona, USA nodules to 950 μm and smaller metal grains decorating chondrule Found: prior to 2005 surfaces. There is minor sulfide. Likely paired with Acfer 394, 396, Classification: Iron meteorite (IIIAB) and 397. Other CR chondrites from Acfer have been found in the History: Purchased by Carleton Moore from the finder in Apache same area and may also be paired with these samples. Junction. Physical characteristics: A single, ellipsoidal (34 × 15 × 12 cm) 25 Acfer 396 27°30.72’N, 3°53.87’E kg mass reportedly found near the intersection of McKellips Rd. Tamanghasset, Algeria and Ironwood Dr. in the city of Apache Junction, Arizona. The Found: Oct 2001 surface of the meteorite exhibits shows minor rusting, and well- Classification: Carbonaceous chondrite (CR2) developed regmaglypts. Petrography: Average chondrule size of 900 μm. There are coarse Petrography: (Laurence Garvie, ASU) Medium octahedrite metal grains in matrix and decorating chondrule surfaces. The metal (bandwidth 0.85±0.15). Kamacite with a cross-hatched pattern grains are up to 1000 μm. Likely paired with Acfer 394, 395, and abundant. Taenite and plessite common (visually ~25% by area). 397. Other CR chondrites from Acfer have been found in the same Neumann bands weakly developed. A few long thin Reichenbach area and may also be paired with these samples. lamellae on each slice. Individual lamellae can be followed through several slices and together these lamella form a trapezoid - parallel Acfer 397 27°30.54’N, 3°53.75’E sides are 35 and 15 mm long and height of ~20 mm. Typical lamella Tamanghasset, Algeria is a 100 μm thick plate of chromite (determined by powder XRD). Found: Oct 2001 Some lamellae bordered by troilite and irregular masses of attached Classification: Carbonaceous chondrite (CR2) schreibersite. Schreibersite (to 500 μm) present in the interiors of Petrography: Average chondrules diameter of 900 μm. There are kamacite bands. Chromite also present as rare, to 1 mm, euhedral coarse metal grains in matrix and decorating chondrule surfaces. grains with schreibersite. Only one troilite nodule (12x8 mm) Metal grains to 650 μm. Likely paired with Acfer 394, 395, and present; exhibits a discontinuous schreibersite rim and well- 396. Other CR chondrites from Acfer have been found in the same developed swathing kamacite. Traces of heat affected zone present. area and may also be paired with these samples. Geochemistry: Composition as determined by INAA (J.T. Wasson, UCLA) - Ni 83.9 mg/g; Co 5.28 mg/g; Cr 18 μg/g; Cu 136 μg/g; Ga Acfer 398 27°30.13’N, 3°51.65’E 20.1 μg/g; As 8.3 μg/g; Ir 0.192 μg/g; Pt 5.7 μg/g; Au 1.153 μg/g; Tamanghasset, Algeria W 0.53 ng/g, and Re <20 ng/g. Found: Oct 2001 Classification: The meteorite is a member of IIIAB. Its nearest Classification: Carbonaceous chondrite (CR2) North American relatives are El Capitan (0.12 μg/g Ir) and Asarco Petrography: Chondrules range from 300-2750 µm in diameter. Mexicana (0.27 μg/g Ir), but the compositional differences are large There are coarse metal grains in the matrix and decorating enough to make it unlikely that it is paired with either of these or chondrule surfaces. The metal grains are up to 1000 µm in with any other well-characterized IIIAB iron. maximum dimension. Likely paired with Acfer 394-400. Specimens: A total of 1500 g are on deposit at ASU. Acfer 399 27°30.16’N, 3°52.35’E Assamakka 19°16’N, 5°55’E Tamanghasset, Algeria Agadez, Niger Found: Oct 2001 Found: 21 Mar 2002 Classification: Carbonaceous chondrite (CR2) Classification: Iron meteorite (IVA, anomalous) Petrography: The average chondrule size is 900 µm in diameter. History: The meteorite was found during a trip through the Sahara Contains coarse metal grains in matrix and decorating chondrule close to Assamaka, Niger. surfaces. The metal grains are up to 1000 µm in maximum Physical characteristics: One flat slightly parabolic fragment of dimension. Likely paired with Acfer 394-400. 4400 g, with flow textures on the surface. Petrography: The meteorite displays typical Widmannstätten Acfer 400 27°30.05’N, 3°51.97’E pattern with 0.2-0.4 mm kamacite bandwidths. Tamanghasset, Algeria Geochemistry: Composition as determined by INAA (C. Koeberl, Found: Oct 2001 UVien) Ni 8.81 wt%, Co 0.386 wt%, Cr 34.4 ppm, As 6.65 ppm, Ir Classification: Carbonaceous chondrite (CR2) 1.49 ppm ppm, Au 290 ppb. E2 Meteoritical Bulletin, No. 100 Classification: Iron meteorite (IVA-an, fine octahedrite). Overall recovered, it was indistinguishable from terrestrial stones and slag the composition is consistent with the IVA class of irons except the found in the field. Au is significantly too low, hence the anomalous designation. Petrography: (Jakub Haloda, PCU) Chondrules indistinct showing Specimens: A total of 68.1 g at MNB. Mr. Josef Geltl, significant recrystallization. Weathering grade W3. Shock features Ostermünchen, Germany holds the main mass. consistent with S3. Geochemistry: Minerals exhibit equilibrated chemical Benešov (a) 49°46’ N, 14°38’ E compositions. Olivine Fa17.8-20.2, with an average value of Fa19.1, Stredocesky, Czech Republic (n=42); low-Ca pyroxene Fs15.7-18.7Wo0.7-1.5, with average of Fs17.1; Found: 9 Apr 2011; possibly fell 7 May 1991 Plagioclase (Ab77-86, An12-19, grain size 6-40 μm) is usually Classification: Ordinary chondrite (LL3.5) associated with high-Ca pyroxene (Fs6.2-9Wo44.2-46.5). History: A -19.5 absolute magnitude fireball was recorded by 3 all- Classification: H5 sky and 2 spectral cameras at 3 Czech stations of the European Specimens: Specimen: 1.54 g, CzAS Fireball Network on May 7, 1991, at 23:03:48 UT. Data on atmospheric trajectory, heliocentric orbit, fragmentation history, Bernic Lake 50°26.307’N, 95°31.762’W composition and possible impact location were subsequently Manitoba, Canada determined (Spurny, 1994; Borovicka and Spurny, 1996; Borovicka Found: October 2002 et al. 1998a; Borovicka et al. 1998b). Despite great efforts no Classification: Iron meteorite (IAB-MG) meteorite was found in the weeks and years after the fall. The History: In October 2002, the discovery of two irregularly shaped fireball observations were re-analyzed by P. Spurny in 2011 and a meteorite fragments weighing 5.5 and 4.3 kg was reported to the revised impact location was determined. The new impact area was Prairie Meteorite Search (run by the Universities of Calgary, probed using metal detectors and three small meteorites were Western Ontario and Regina) by Derek Erstelle from Winnipeg, discovered - two named as Benešov (a) and one named as Benešov Manitoba. The discovery site is east of Lac du Bonnet, 3.6 km from (b). The two Benešov (a) fragments were 250 m apart. Benešov (b) the junction with Highway 315 along the Tanco Mine Road. Bernic was found between them. Lake, the site of the Tanco Mine, is the nearest geographical feature Physical characteristics: Weathered fragments lacking fusion and is the source of the name. The two fragments were found in a crust. The meteorites resemble the terrestrial stones and slag found sandy area within 5 m of each other.