 | | Journal (article/letter/editorial) | | Petrography of isotopically-dated clasts in the Kapoeta howardite and petrologic constraints on the evolution...basaltic rock fragments separated from the howardite Kapoeta. Clasts C and p have been dated at -4.55 AE and...melt. They thus provide good evidence that the Kapoeta parent body produced basaltic magmas shortly after...‘young’ magmatism on the Kapoeta parent body. Kapoeta is a ‘regolith’ meteorite, and mineral-chemical and...orthopyroxenites to very iron-rich basalts. The Fe0 and MnO contents of all pyroxenes in Kapoeta fall near a line |  | | Journal (article/letter/editorial) | | Exposure history of separated phases from the Kapoeta meteorite MARCW. CAFFEEI * AND KUNIHIKO NISHIIZUMI2...selected clasts and matrix samples from the howardite Kapoeta. Previous measurements of cosmogenic 21Ne indicate...ages is a complex recent exposure history for Kapoeta. In this scenario some constituents are exposed...cosmogenic radionuclides in several clasts from Kapoeta. These measurements are consistent with a simple...in which the exposure of some constituents o f Kapoeta to energetic particles occurred at an earlier time |  | | Journal (article/letter/editorial) | | NORTH-HOLLAND PUBLISHING COMPANY THE EVOLUTION OF THE KAPOETA HOWARDITE BASED ON FOSSIL TRACK STUDIES Laurel...particle track densities in the gas-rich howardite, Kapoeta. In addition to the high track density pyroxene...track-rich grains in the dark gas-rich portion of the meteorite is random. Grains that are track.rich are not...during the extensive breeeiation and mixing of Kapoeta parent materials. 1. Introduction The gases in...subsequent analyses by Fredriksson and Keil [4] of the Kapoeta achondrite and the Pantar chondrite showed that |  | | Journal (article/letter/editorial) | | weathering products, such as agglutinates and nanophase iron-bearing rims are easily preserved through lithification...regolith breccia meteorites, Fayetteville (H4) and Kapoeta (howardite), was undertaken to search for physical...Extensive friction melt was discovered in the meteorite that is difficult to differentiate from weathered...one possible npFe0-bearing rim were identified in Kapoeta. The existence of these products suggests that...single-domain metallic iron particles, commonly called nanophase iron (npFe0) or submicroscopic iron (Keller and |  | | Journal (article/letter/editorial) | | with the Mossbauer experiments reported for the Kapoeta howardite and look for systematics in the Mossbauer...Mossbauer spectra of HED meteorites. INTRODUCTION Iron-bearing minerals are important constituents of meteorites...technique is still underutilized in the field of meteorite research. From our studies on several chondrites...gain information about the category of a given meteorite. Eucrites and howardites belong to the same category... The Meteorites Under Study The Piplia Kalan meteorite fell on 1996 June 20 at 20:15 h IST at Piplia |  | | Journal (article/letter/editorial) | | investigation of xenolithic carbonaceous clasts from the kapoeta howardite Nan Liu, Ryan C. Ogliore, Lionel G. Vacher...investigation of xenolithic carbonaceous clasts from the kapoeta howardite, Geochimica et Cosmochimica Acta (2020)...Investigation of Xenolithic Carbonaceous Clasts from the Kapoeta Howardite Nan Liu1*, Ryan C. Ogliore1, Lionel G...carbonaceous clasts (C-clasts) identified in the Kapoeta howardite based on highresolution NanoSIMS hydrogen...in the asteroid belt, is differentiated with an iron-rich core, a silicate mantle, and a basaltic crust |  | | Journal (article/letter/editorial) | | University Corvallis, OR 97331 Paul P. Sipiera Meteorite Research Group William Rainey Harper College Palatine...from olivine-normative to quartz-normative. Like Kapoeta, it contains pyroxene grains that range up to highly...those occurring in diogenites, Monticello and Kapoeta are exceptions to the simple two-component mixing...Jones, discovered the Monticello meteorite on 29 May 1982. The meteorite was lying on the shoreline of Lake...Among reasonable explanations it is possible the meteorite fell into ~hallow water and the rapid quench caused |  | Macdougall, Douglas J., Lal, Devendra, Wilkening, Laurel L., Bhat, Suman G., Liang, Samuel S., Arrhenius, Gustaf, Tamhane, Arvind S. (1971) Techniques for the study of fossil tracks in extraterrestrial and terrestrial samples. I: Methods of high contrast and high resolution study. GEOCHEMICAL JOURNAL, 5 (2) 95-112 doi:10.2343/geochemj.5.95 | Journal (article/letter/editorial) | | tracks, and the availability of a large number of meteorite and documented lunar samples. The latter exhibit...(b) Silveredtracks in a pyroxene from the Kapoeta meteorite. Track density is 5 X 106cm2. (c) Optically...tracks 15 LENGTH showing well-etched in the meteorite, 20 (MICRONS) the length tracks distribution...lengths of neutron induced fission tracks in the meteorite Angra dos Reis. Two types of tracks were selected...County et al. i) Tip 1 ii) Tip 1 Track No. meteorite: i) 6:4, ii) 6:4, Etchings 50. 25 Length (microns) |  | | Journal (article/letter/editorial) | | of fission xenon in four meteorites (Pasamonte, Kapoeta, Angra dos Reis, and St. Severin) has been reevaluated...of the fission Xe composition in St. Severin, Kapoeta, and Pasamonte is 12SXe/129Xe/130Xe/l a l X e /...the achondrites Pasamonte, Angra dos Reis, and Kapoeta and the chondrite St. Severin previously derived... Severin whitlockite =-100 ~100 100 ±50 ~100 Kapoeta ~100 Pasamonte -~100 =-100 Trapped Xe 13aXe ...available. In this paper, we reexamine the available meteorite data and recompute the meteoritic fission spectrum |  | | Journal (article/letter/editorial) | | and glass, features observed in the howardites Kapoeta (Brownlee and Rajan, 1973), Malvern (Jerome and...although smaller and larger spherules occur in the meteorite. Glass fragments recovered probably have been...through the magnesiumrich howardite group into the iron-rich eucrite group. These glass analyses may represent...and glass. The breccias are formed by repeated meteorite impact, mixing and welding of fines, breccia and...1 100.16 0.32 (0.29-0.36) 1967. The Bununu meteorite, and a discussion of the pyroxene-plagioclase |  | | Journal (article/letter/editorial) | | USA Cosmogenic neon in mineral separates from Kapoeta: No evidence for an irradiation of its parent body...plagioclase separates from the solar noble-gas-rich meteorite Kapoeta, obtained mainly by in vucuo etching. Samples...irradiation by galactic cosmic rays (GCR) on the meteorite parent body. In the former case, gas-rich meteorites...proposed by M. N. Rao and coworkers for the howardite Kapoeta and for gas-rich ordinary chondrites (e.g., Fayetteville)...study whether the cosmogenic noble gas record in Kapoeta may similarly be explained by a long parent body |  | | Journal (article/letter/editorial) | | of glass fragments produced by impact on the meteorite body. The release pattern for the glass from the...with similar young ages for igneous clasts from Kapoeta clearly show that the regoliths were extant on...7 AE ago. 1. Introduction The first gas-rich meteorite was discovered by Getling and Levskii [ 1], who...the grains had indeed been bombarded by lowenergy iron group nuclei from solar flares ( 2 - 1 0 MeV/N)...discovery of hypervelocity micro-meteorite craters on certain grains of Kapoeta ]6], as well as glassy agglutinate-like |  | | Journal (article/letter/editorial) | | including nontronite) with admixed salts and magnetic iron oxides. This interpretation, if correct, requires...In addition, certain synthetic gels of silica and iron hydroxide produce good spectral matches. It should...spectral reflectance results to be consistent with iron-rich weathering products such as limonite and nontronite;...amounts of HzO and COO in fines FIG. 1. Correlationof iron with titaniumin Martian regolith fines from Planitia...re- day Martian regolith. sponses consistent with iron-rich calcic pyroxene (Huguenin et al., 1977). Maderazzo |  | | Journal (article/letter/editorial) | | M. OvEBsBY: The isotopic composition of lesd in iron meteorites . F. J. STEVENSONend C-N. CHENO: Amino... M. HOEENBERQ: Xenon from the Angre dos Reis meteorite . M. A. Rurrrn and L. H. KING: Mejor oxygen-cont&ning...and the relationship between Si and Cr in reduced iron meteorites . . . . . . C. K.ENT Ba009s: The concentrations... . , 399 401 408 411 416 421 Book Review: “Meteorite Addendum Research” . . Edited by Peter M....thermal histories of iron P. E. FRICSES, 6. I. *oLDSTDXN and A. L. SW: and stony-iron meteorites . . . |  | | Report (issue) | | parent rocks. Introduction As the importance of meteorite impacts as a mechanism producing lunar land forms... Alteration minerals include chlorite minerals, iron oxides, serpentine, and epidote. In addition, within...chromespinel, ulvospinel, rutile, metallic iron, nickel-iron, and troilite). Minor olivine may also be...basalt (Figure 11, Tables 1, 2). In addition, ferrous iron is more prevalent in the glasses, indicating a reduction...the Lake Wilson-Mt. Davies region in northwest South Australia; (2) a group with high Ca/Al ratio centered |  | | Journal (article/letter/editorial) | | (Pu/U)~.~S~~~= 0.045. Brecciation of the Bhola meteorite must have occurred at 24.3 Gyr to account for...ages date the end of metamorphic cooling in the meteorite parent bodies and support the planetesimal model...meteorites. These are 3.5 Gyr for basaltic achondrite Kapoeta (Rajan et af., 1979), 1.4 Gyr for St. Mesmin (Schultz... for example, in a matrix sample of gas-rich meteorite. to find that only some of the phosphates have...deducting the contribution from all other sources. (c) Iron group nuclei of cosmic rays--This is estimated by |  | Lunning, Nicole G., Welten, Kees C., McSween, Harry Y., Caffee, Marc W., Beck, Andrew W. (2016) Grosvenor Mountains 95 howardite pairing group: Insights into the surface regolith of asteroid 4 Vesta. Meteoritics & Planetary Science, 51 (1) 167-194 doi:10.1111/maps.12580 | Journal (article/letter/editorial) | | cm, a preatmospheric size comparable to that of Kapoeta, the largest known regolithic howardite. The paired...features of the groups and subgroups of the HED meteorite clan are outlined in Table 1. In this study, we...evaluate which stones may have been part of a single meteorite fall that broke apart during atmospheric transit...of the howardite, eucrite, and diogenite (HED) meteorite clan. Multiple lithologies have previously been...meteorites and Vesta. First, the mass of Vesta’s iron-nickel core constrained from geophysical measurements |  | | Journal (article/letter/editorial) | | WDOWIAK, P. CLAEYS AND G. IZETT: Presence of an iron-rich nanophase material in the upper layer of the...................... .... phases from the Kapoeta meteorite ............................................and petrology of the Dar al Gani 476 martian meteorite: Implications for its cooling history and relationship...Low-temperature phase decomposition in iron-nickel metal of the Portales Valley meteorite ...........................noble ga al and graphite of the Bohumilitz IAB iron meteorite ....................................... .. |  | Cartwright, J.A., Ott, U., Mittlefehldt, D.W., Herrin, J.S., Herrmann, S., Mertzman, S.A., Mertzman, K.R., Peng, Z.X., Quinn, J.E. (2013) The quest for regolithic howardites. Part 1: Two trends uncovered using noble gases. Geochimica et Cosmochimica Acta, 105. 395-421 doi:10.1016/j.gca.2012.11.047 | Journal (article/letter/editorial) | | HED clan – represent the largest achondritic meteorite clan, comprising of over 1000 named stones. Telescopic...particular interest is Vesta’s partially-demolished south pole, which was likely created by a 42 km impactor...can help determine the regolithic nature of a meteorite, by allowing for the resolution between solar...of five howardites – Bholghati, Bununu, Jodzie, Kapoeta and Malvern, that they denote “regolithic”. Whilst...and by SCR. Whilst Bholghati, Bununu, Jodzie and Kapoeta show strong evidence for a SW-like component, Malvern |  | Mittlefehldt, David W., Herrin, Jason S., Quinn, Julie E., Mertzman, Stanley A., Cartwright, Julia A., Mertzman, Karen R., Peng, Zhan X. (2013) Composition and petrology of HED polymict breccias: The regolith of (4) Vesta. Meteoritics & Planetary Science, 48 (11) 2105-2134 doi:10.1111/maps.12182 | Journal (article/letter/editorial) | | 95535, GRO 95602, Lewis Cliff (LEW) 85313, and Meteorite Hills (MET) 00423. We suggest that EET 87503 is...masses, indicating that obtaining representative meteorite compositions requires multiple or large samples...characteristic mixing ratio for well-mixed vestan regolith. Kapoeta, the prototypical example of a regolithic howardite...track studies show that track-rich grains occur in Kapoeta (Lal and Rajan 1969; Pellas et al. 1969), and that...implanted Ne with a solar 20 Ne/22Ne ratio in Kapoeta. Glassy spherules containing microcraters caused |  | | Journal (article/letter/editorial) | | link, and provide a geological context for the meteorite group (De Sanctis et al., 2012; Prettyman et al...example, with reports confirming the presence of an iron-nickel core, with a radius of ~110 km (Russell et...meteorites. 2.2.1 Noble gas components in HEDs: Meteorite samples usually contain mixtures of solar, planetary...PROCEDURE Bulk fragments of the howardites from the Meteorite Working Group (MWG) collection (all recovered...a similar concentration again hints that this meteorite is a complex mixture of planetary dominated and |  | Hörz, F., Brownlee, D.E., Fechtig, H., Hartung, J.B., Morrison, D.A., Neukum, G., Schneider, E., Vedder, J.F., Gault, D.E. (1975) Lunar microcraters: Implications for the micrometeoroid complex. Planetary and Space Science, 23 (1) 151-172 doi:10.1016/0032-0633(75)90076-8 | Journal (article/letter/editorial) | | fraction of particles could have densities as high as iron. Figure 4 apparently implies that most micrometeoroids...chondritic meteorites. These recent developments in meteorite research were largely stimulated by detailed studies...computed values that were based on present-day meteorite fluxes derived from satellites. Neukum (1973)...dislodged from the interior of the Kapoeta meteorite. This meteorite is a loosely consolidated microbreccia...breccias in many aspects. The formation age of Kapoeta is not known, but believed to be in excess of 4 |  | | Journal (article/letter/editorial) | | Therefore, a large variety of compounds containing iron can be studied by Mössbauer spectroscopy. It is...well known that planetary matter contains various iron-bearing phases and minerals. Therefore, the extraterrestrial...meteorites; Moon; Mars; iron-bearing minerals; 57 Fe hyperfine interactions; iron-bearing phase composition;...equilibrium distribution in silicate phases; meteorite weathering; fusion crust Received: 14 January...57 Fe nucleus and, therefore, is related to the iron valence/spin state; (ii) quadrupole splitting ∆EQ |  | Harries, Dennis, Yakame, Shogo, Karouji, Yuzuru, Uesugi, Masayuki, Langenhorst, Falko (2016) Secondary submicrometer impact cratering on the surface of asteroid 25143 Itokawa. Earth and Planetary Science Letters, 450. 337-345 doi:10.1016/j.epsl.2016.06.033 | Journal (article/letter/editorial) | | 1979) and from the meteoritic regolith breccias Kapoeta (howardite; Brownlee and Rajan, 1973) and Murchison...impactor and not produced by in-situ reduction of iron within the target pyroxene (Sasaki et al., 2002)...Langenhorst, 2014). We did not observe nanophase metallic iron (np-Fe0 ) particles within the layer, nor did we...observed in the Tenham chondrite and the Martian meteorite Zagami, which both experienced strong shock metamorphism...bulk metal, respectively; Jarosewich, 1990) or some iron meteorites, but the small sample volume renders |  | | Journal (article/letter/editorial) | | two yield 104 D. A. EDGERLEY Table 132Xe Meteorite Fraction Clover ccSTP/g Springs 400°C (Mesosiderite)...component remaining from the initial condensation of meteorite material. While atmospheric contamination is expected...spallation Xe have been determined in a variety of meteorite samples resulting in an equally diverse selection...spallation composition and how it varies with meteorite type, composition, and cosmic-ray history are...to the heavier isotopes. In addition fission meteorite Xe isotope patterns may be represent Xe abundance |
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