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Artículos de revistas sobre el tema "Meteorites – Antarctica"

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Publicado: 4 de junio de 2021

Última modificación: 8 de febrero de 2022

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1

Wadhwa, Meenakshi, Timothy J. McCoy y Devin L. Schrader. "Advances in Cosmochemistry Enabled by Antarctic Meteorites". Annual Review of Earth and Planetary Sciences 48, n.º 1 (30 de mayo de 2020): 233–58. http://dx.doi.org/10.1146/annurev-earth-082719-055815.

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At present, meteorites collected in Antarctica dominate the total number of the world's known meteorites. We focus here on the scientific advances in cosmochemistry and planetary science that have been enabled by access to, and investigations of, these Antarctic meteorites. A meteorite recovered during one of the earliest field seasons of systematic searches, Elephant Moraine (EET) A79001, was identified as having originated on Mars based on the composition of gases released from shock melt pockets in this rock. Subsequently, the first lunar meteorite, Allan Hills (ALH) 81005, was also recovered from the Antarctic. Since then, many more meteorites belonging to these two classes of planetary meteorites, as well as other previously rare or unknown classes of meteorites (particularly primitive chondrites and achondrites), have been recovered from Antarctica. Studies of these samples are providing unique insights into the origin and evolution of the Solar System and planetary bodies. ▪ Antarctic meteorites dominate the inventory of the world's known meteorites and provide access to new types of planetary and asteroidal materials. ▪ The first meteorites recognized to be of lunar and martian origin were collected from Antarctica and provided unique constraints on the evolution of the Moon and Mars. ▪ Previously rare or unknown classes of meteorites have been recovered from Antarctica and provide new insights into the origin and evolution of the Solar System.

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2

Graham, A. L. y John O. Annexstad. "Antarctic meteorites". Antarctic Science 1, n.º 1 (marzo de 1989): 3–14. http://dx.doi.org/10.1017/s0954102089000039.

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Antarctica is currently the most productive region of the Earth for the recovery of meteorites and over 9800 specimens have been found there, most of these since 1969. This material consists of meteoritic fragments representing a much smaller, but unknown, number of distinct meteorites. The particular climatic and environmental conditions of Antarctica result in the recovery of a much larger fraction of the extraterrestrial material that falls to Earth than would be the case in other regions. Remarkable concentrations of meteorites are found in some ‘blue ice’ areas resulting from the movement and ablation of the ice. Most meteorites are believed to have been derived from asteroids less then 200 km in diameter. The discovery in Antarctica of meteorites of lunar material proved that other sources are possible. Indeed two meteorites from Antarctica may have come from the planet Mars. Antarctic meteorites have much older terrestrial ages than non-Antarctic specimens and may be used to obtain information on the movement of the ice sheets in the past.

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3

Wilson, John W., Liam A. Marsh, Wouter Van Verre, Michael C. Rose, Geoffrey Evatt, Andrew R. D. Smedley y Anthony J. Peyton. "Design and construction of a bespoke system for the detection of buried, iron-rich meteorites in Antarctica". Antarctic Science 32, n.º 1 (22 de enero de 2020): 58–69. http://dx.doi.org/10.1017/s0954102019000531.

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AbstractIron-rich meteorites are significantly underrepresented in collection statistics from Antarctica. This has led to a hypothesis that there is a sparse layer of iron-rich meteorites hidden below the surface of the ice, thereby explaining the apparent shortfall. As standard Antarctic meteorite collecting techniques rely upon a visual surface search approach, the need has thus arisen to develop a system that can detect iron objects under a few tens of centimetres of ice, where the expected number density is of the order one per square kilometre. To help answer this hypothesis, a large-scale pulse induction metal detector array has been constructed for deployment in Antarctica. The metal detector array is 6 m wide, able to travel at 15 km h-1 and can scan 1 km2 in ~11 hours. This paper details the construction of the metal detector system with respect to design criteria, notably the ruggedization of the system for Antarctic deployment. Some preliminary results from UK and Antarctic testing are presented. We show that the system performs as specified and should reach the pre-agreed target of the detection of a 100 g iron meteorite at 300 mm when deployed in Antarctica.

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4

Leary, David. "Blue Ice, Meteorites, Fossil Penguins and Rare Minerals: The Case for Enhanced Protection of Antarctica’s Unique Geoheritage – An International Legal Analysis". Yearbook of Polar Law Online 12, n.º 1 (13 de diciembre de 2021): 17–40. http://dx.doi.org/10.1163/22116427_012010004.

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Its isolation and extreme climate means Antarctica is one of the world’s richest regions for untouched geoheritage. The potential of mining in Antarctica is often talked of in public discourse as a future threat to Antarctica even though the prohibition on mining is absolute and is likely to stay so indefinitely. As such mining does not pose a realistic threat to Antarctica’s geoheritage. The impacts of scientific research and tourism pose more pressing challenges to Antarctica’s geoheritage. This paper considers emerging debates in the Antarctic Treaty System on the need for further protection of Antarctica’s geoheritage. After considering the concept of geoheritage the paper considers key threats to Antarctic geoheritage. The role of Antarctic Specially Protected Area system in the protection of Antarctica’s geoheritage is then considered as is the draft code of conduct on geosciences field research currently being developed within the Antarctic Treaty System. The final part of the paper then goes on to examine how the Antarctic Treaty system could in part draw on the experience of other international initiatives, including the frameworks associated with the UNESCO Global Geoparks movement in developing an Antarctic System for protection of geoheritage.

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5

Bland, Philip A., Alex W. R. Bevan y A. J. Tim Jull. "Ancient Meteorite Finds and the Earth's Surface Environment". Quaternary Research 53, n.º 2 (marzo de 2000): 131–42. http://dx.doi.org/10.1006/qres.1999.2106.

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AbstractThe flux of meteorites to the Earth over the last 50,000 yr has remained approximately constant. Most meteorites that fall in temperate or tropical areas are destroyed on a time scale which is short compared to the rate of infall; however, in arid regions (both “hot” deserts and the “cold” desert of Antarctica) weathering is slower and accumulations of meteorites may occur. The initial composition for many meteorite groups is well known from modern falls, and terrestrial ages may be established from analyses of the abundance of cosmogenic radionuclides, providing an absolute chronology for recording terrestrial processes. As samples are falling constantly, and are distributed approximately evenly over the Earth, meteorites may thus be thought of as an appropriate “standard sample” for studying aspects of the terrestrial surface environment. Studies involving 14C and 36Cl terrestrial ages of meteorites, 57Fe Mössbauer spectroscopy (to quantify the degree of oxidation in samples), stable isotopes, and determination of halogen abundances are yielding information on the terrestrial history of meteorites: (i) terrestrial age and oxidation-frequency distributions for populations of samples allow the ages of surfaces to be estimated; (ii) differences in the weathering rate of samples between sites allows constraints to be imposed on the effect of climate on rock weathering rates; (iii) carbon isotopic compositions of generations of carbonate growth within meteorites allows, in some cases, temperatures of formation of carbonates to be estimated; (iv) structure in the oxidation–terrestrial age distribution for meteorites from some arid accumulation sites (specifically, the Nullarbor of Australia) appears to be linked to previous humid/arid cycles; (v) meteorite accumulations in Antarctica have been used to constrain aspects of the Quaternary evolution of the ice sheet, and terrestrial age and oxidation data have been used to constrain ice flow.

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6

Korotev, Randy L. "Meteorites, ice, and antarctica." Geochimica et Cosmochimica Acta 68, n.º 10 (mayo de 2004): 2399. http://dx.doi.org/10.1016/j.gca.2003.12.011.

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7

Carmichael, Stephen W. "Out of this World!" Microscopy Today 4, n.º 8 (octubre de 1996): 3–5. http://dx.doi.org/10.1017/s1551929500063616.

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If you have been hibernating for several weeks you may have missed the headlines and magazine covers exclaiming about “Life on Mars!” The basis for all of this excitement is an article in Science by Dr. David S. McKay of the Lyndon B. Johnson Space Center in Houston and eight of his colleagues from several academic institutions. The reader of this column will not be surprised by the fact that microscopes were used to detect evidence of life on a meteorite from Mars.The first consideration was whether or not the meteorite was in fact a fragment of the martian surface. The specimen, known as ALH84001, is from a class of meteorites that appear to have resulted from impacts on Mars, some of the specimens landing in Antarctica where this one was recovered. Trapped gases (in glass droplets and stringers) in several of the family of meteorites closely match the martian atmosphere for several gases over 8 orders of magnitude range in abundance. Whereas ALHB4001 did not contain such trapped atmospheric gases, its elemental and isotopic composition closely resemble the meteorites that do.

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8

Zolensky, Michael. "The flux of meteorites to Antarctica". Geological Society, London, Special Publications 140, n.º 1 (1998): 93–104. http://dx.doi.org/10.1144/gsl.sp.1998.140.01.09.

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9

Wang, Bao Hua, Shi Jie Li y Bing Kui Miao. "The Mineral Chemistry and Classification of New Ordinary Chondrites Collected in Antarctica". Advanced Materials Research 621 (diciembre de 2012): 125–29. http://dx.doi.org/10.4028/www.scientific.net/amr.621.125.

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Petrography and mineral chemistry of ninety-eight ordinary chondrites from Grove Mountains, Antarctica, have been studied, in order to assign their chemical-petrographic types. The chemical-petrographic types of these meteorites are presented below: 36 H-groups (21 H4, 9 H5, 6 H6) and 62 L-groups (25 L5, 37 L6). The compositions of olivines and low-Ca pyroxenes in the all these ordinary chondrites have similar composition, respectively, reflecting some degree thermodynamics equilibration in them. The weathering degrees of all the ordinary chondrites, consisting of predominant weathering degrees of W1, suggest lightly weathered among them. More than 30% meteorites experienced severe shock metamorphism, as indicated by the presences of shock-induced melt veins and pockets. These heavily shocked meteorites provide us with natural samples for study of high-pressure polymorphs of minerals.

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10

Genge, Matthew. "Meteorites, ice, and Antarctica, by William A. Cassidy". Meteoritics & Planetary Science 39, n.º 1 (enero de 2004): 157–58. http://dx.doi.org/10.1111/j.1945-5100.2004.tb00055.x.

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11

Endo, Kazutoyo, Rieko Hirunuma, Taeko Shinonaga, Mitsuru Ebihara y Hiromichi Nakahara. "Mössbauer spectroscopic study of meteorites recovered on Antarctica". Hyperfine Interactions 91, n.º 1 (diciembre de 1994): 557–61. http://dx.doi.org/10.1007/bf02064570.

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12

Wang, Ming-Sheng y Michael E. Lipschutz. "Thermal Metamorphism of Primitive Meteorites—XII. The Enstatite Chondrites Revisited". Environmental Chemistry 2, n.º 3 (2005): 215. http://dx.doi.org/10.1071/en04075.

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Environmental Context.The first Solar System material condensed 4.567 billion years ago, rapidly forming planetesimals—solid bodies that might combine to form planets (accretion) or survive as asteroidal meteorites. Earth’s main accretion ended within the next 30 million years, but subsequent high temperatures essentially erased evidence of this history. However, heating in these early episodes produced effects uniquely recorded by 14 volatile trace elements. The volatile element composition of chondritic meteorites, whose parent material formed closest to Earth, may thus provide important information about early planetesimal evolution. Abstract.We report data for 14 trace and ultratrace elements—Au, Co, Sb, Ga, Rb, Ag, Cs, Te, Zn, Cd, Bi, Tl, In (ordered by increasing putative nebular volatility)—in 13 enstatite (E) chondrites recovered from Antarctica and two E inclusions in the Kaidun polymict breccia that fell in 1980. These data, determined by radiochemical neutron activation analysis (RNAA), essentially double the amount of information known for E chondrites, whose parent materials formed closest to the Sun in the chondrite-forming nebular region. We discuss here the data for all 29 samples studied. The meteoritic suite studied here includes both representatives of previously rare types—like high-iron EH3 and EH5 individuals—but also unique individuals and previously unknown low-iron, EL3, chondrites. Prior hypothetical assertions by others are corrected by the new data. Volatile element contents of EL3 and EH3 chondrites are variable, but comparable, like those of type 3 ordinary chondrites (i.e. H3, L3, and LL3). Volatile element contents of EH4 chondrites are at least as high as those of the E3 types, in contrast to the lower contents of H4, L4, and LL4 types. Compositionally, E3,4 chondrites reflect only nebular condensation and/or accretion processes. Volatiles in E5 and E6 chondrites—whether of EH, EL or unique ones—are depleted relative to cosmic (i.e. CI1) or E3,4 chondrite abundances. The evidence indicates that E5,6 chondrites compositionally reflect vaporization and loss of volatiles during open-system, thermal metamorphism of their parent(s); this may have been the terrestrial environment during Earth’s formation from early planetesimals. Compositional differences between Antarctic E5,6 chondrites and contemporary falls probably do not reflect weathering during the long residence of these chondrites in Antarctica. They might reflect differences in the starting compositions and/or metamorphic conditions in the parent(s).

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13

Smith, Joseph P., Frank C. Smith y Karl S. Booksh. "Multivariate Curve Resolution–Alternating Least Squares (MCR-ALS) with Raman Imaging Applied to Lunar Meteorites". Applied Spectroscopy 72, n.º 3 (11 de agosto de 2017): 404–19. http://dx.doi.org/10.1177/0003702817721715.

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Lunar meteorites provide a more random sampling of the surface of the Moon than do the returned lunar samples, and they provide valuable information to help estimate the chemical composition of the lunar crust, the lunar mantle, and the bulk Moon. As of July 2014, ∼96 lunar meteorites had been documented and ten of these are unbrecciated mare basalts. Using Raman imaging with multivariate curve resolution–alternating least squares (MCR-ALS), we investigated portions of polished thin sections of paired, unbrecciated, mare-basalt lunar meteorites that had been collected from the LaPaz Icefield (LAP) of Antarctica—LAP 02205 and LAP 04841. Polarized light microscopy displays that both meteorites are heterogeneous and consist of polydispersed sized and shaped particles of varying chemical composition. For two distinct probed areas within each meteorite, the individual chemical species and associated chemical maps were elucidated using MCR-ALS applied to Raman hyperspectral images. For LAP 02205, spatially and spectrally resolved clinopyroxene, ilmenite, substrate-adhesive epoxy, and diamond polish were observed within the probed areas. Similarly, for LAP 04841, spatially resolved chemical images with corresponding resolved Raman spectra of clinopyroxene, troilite, a high-temperature polymorph of anorthite, substrate-adhesive epoxy, and diamond polish were generated. In both LAP 02205 and LAP 04841, substrate-adhesive epoxy and diamond polish were more readily observed within fractures/veinlet features. Spectrally diverse clinopyroxenes were resolved in LAP 04841. Factors that allow these resolved clinopyroxenes to be differentiated include crystal orientation, spatially distinct chemical zoning of pyroxene crystals, and/or chemical and molecular composition. The minerals identified using this analytical methodology—clinopyroxene, anorthite, ilmenite, and troilite—are consistent with the results of previous studies of the two meteorites using electron microprobe analysis. To our knowledge, this is the first report of MCR-ALS with Raman imaging used for the investigation of both lunar and other types of meteorites. We have demonstrated the use of multivariate analysis methods, namely MCR-ALS, with Raman imaging to investigate heterogeneous lunar meteorites. Our analytical methodology can be used to elucidate the chemical, molecular, and structural characteristics of phases in a host of complex, heterogeneous geological, geochemical, and extraterrestrial materials.

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14

EUGSTER, O. "History of Meteorites from the Moon Collected in Antarctica". Science 245, n.º 4923 (15 de septiembre de 1989): 1197–202. http://dx.doi.org/10.1126/science.245.4923.1197.

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15

Jull, A. J. T., S. Cloudt y E. Cielaszyk. "14C terrestrial ages of meteorites from Victoria Land, Antarctica, and the infall rates of meteorites". Geological Society, London, Special Publications 140, n.º 1 (1998): 75–91. http://dx.doi.org/10.1144/gsl.sp.1998.140.01.08.

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16

Wasson, J. T. "Ungrouped Iron Meteorites in Antarctica: Origin of Anomalously High Abundance". Science 249, n.º 4971 (24 de agosto de 1990): 900–902. http://dx.doi.org/10.1126/science.249.4971.900.

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17

Calogero, Sandro, Lorenzo Stievano y Paul H. Benoit. "Mössbauer and thermoluminescence studies of meteorites from Frontier Mountain, Antarctica". Journal of Geophysical Research: Planets 104, E12 (1 de diciembre de 1999): 30817–23. http://dx.doi.org/10.1029/1999je001074.

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18

Sephton, M. A., P. A. Bland, C. T. Pillinger y I. Gilmour. "The preservation state of organic matter in meteorites from Antarctica". Meteoritics & Planetary Science 39, n.º 5 (mayo de 2004): 747–54. http://dx.doi.org/10.1111/j.1945-5100.2004.tb00116.x.

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19

Evans, Mike. "Meteorites, Ice and Antarctica: A Personal Account, by William A. Cassidy". Contemporary Physics 53, n.º 6 (noviembre de 2012): 506–7. http://dx.doi.org/10.1080/00107514.2012.732968.

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20

Swain, Ashit Kumar. "Status Note on Indian Attempts to Search for Meteorites in Antarctica". Journal of the Geological Society of India 97, n.º 8 (agosto de 2021): 915–22. http://dx.doi.org/10.1007/s12594-021-1791-2.

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21

Schwenzer, S. P., R. C. Greenwood, S. P. Kelley, U. Ott, A. G. Tindle, R. Haubold, S. Herrmann et al. "Quantifying noble gas contamination during terrestrial alteration in Martian meteorites from Antarctica". Meteoritics & Planetary Science 48, n.º 6 (10 de abril de 2013): 929–54. http://dx.doi.org/10.1111/maps.12110.

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22

Fogg, G. E. "A century of Antarctic science; planning and serendipity". Archives of Natural History 32, n.º 2 (octubre de 2005): 129–43. http://dx.doi.org/10.3366/anh.2005.32.2.129.

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The British National Antarctic Expedition planned with discreditable bickering, sailed for the Antarctic in 1901 on the Discovery. The venture was well equipped and commanded by R. F. Scott who, without scientific training himself, was nevertheless remarkably in empathy with his scientists. The expedition was foremost among those dispatched around the same time in establishing basic knowledge of the continent. Followed by the second Scott expedition and those of Shackleton and Mawson, a cadre of able and enthusiastic scientists was established. The second involvement of the Discovery in Antarctic exploration was planned without quarrels and with unusual understanding of science by a government department, resulting in a massive accumulation of knowledge about the Southern Ocean. United States expeditions began in 1928, introducing modern technology, thereby extending greatly the scope of Antarctic research. The Norwegian-British-Swedish expedition of 1949–1952 put planned science before geographical exploration. The International Geophysical Year of 1957–1958, supported by governments and planned by international committees, achieved great success. Science has flourished in Antarctica with unplanned and serendipitous findings emerging, for example, the structure of the magnetosphere, collection of meteorites by ice movements, the microbial life of the apparently sterile Dry Valleys and the discovery of the ozone “hole”.

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23

Sears, Derek. "The thermoluminescence of meteorites: A brief 2010 perspective". Geochronometria 38, n.º 3 (1 de septiembre de 2011): 303–13. http://dx.doi.org/10.2478/s13386-011-0036-3.

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AbstractEarly work on meteorite thermoluminescence, influenced by pottery dating and dosimetry applications, demonstrated a relationship between natural thermoluminescence and (1) the orbital perihelion of a meteorite and (2) the terrestrial age (time since fall) of a meteorite. For 14 years natural TL measurements were routinely made on newly recovered Antarctic meteorites to help identify unusual thermal and radiation histories, and to sort them by terrestrial age and perihelion. Two examples of the value of such data are presented, an Antarctic meteorite that underwent a major orbit change prior to fall and the collection mechanics of meteorites at the Lewis Cliff collection site. A second major area of focus for meteorite TL, that has no non-meteorite heritage, is the use of their induced TL to provide an extraordinarily sensitive and quantitative means of exploring metamorphic intensity and palaeothermometry. While especially valuable for unequilibrated ordinary chondrites, these types of measurement have proved useful with virtually every major class of meteorite, asteroidal and planetary. The challenge now is to extend the technique to small particles, micrometeorites, interplanetary dust particles, and cometary particles.

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24

Benoit, P. H., J. Roth, H. Sears y D. W. G. Sears. "The natural thermoluminescence of meteorites: 7. Ordinary chondrites from the Elephant Moraine region, Antarctica". Journal of Geophysical Research 99, E1 (1994): 2073. http://dx.doi.org/10.1029/93je02474.

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25

Folco, Luigi, Pierre Rochette, Jérôme Gattacceca y Natale Perchiazzi. "In situ identification, pairing, and classification of meteorites from Antarctica through magnetic susceptibility measurements". Meteoritics & Planetary Science 41, n.º 3 (marzo de 2006): 343–53. http://dx.doi.org/10.1111/j.1945-5100.2006.tb00467.x.

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26

Lucchitta, B. K., K. Edwards, E. M. Eliason y J. Bowell. "Multi-Spectral Landsat Image Maps of Antarctica (Abstract)". Annals of Glaciology 9 (1987): 250. http://dx.doi.org/10.1017/s0260305500000926.

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The US Geological Survey is conducting a program to prepare digitally enhanced Multispectral Scanner (MSS) Landsat images of Antarctica. The goal is to furnish accurate planimetric, false-colour composite image maps in Lambert conformal conic projection for the following purposes: (1) to locate and delineate blue-ice areas for the collection of meteorites; (2) to produce special purpose maps showing selected features; (3) to provide synoptic views that aid in the detection and interpretation of glaciological features associated with the inland ice sheet, outlet glaciers, ice streams, and ice shelves; (4) to monitor changes in coastline and glacial features; (5) to enable the superposition and correlation of different types of digital cartographic data; and (6) to furnish spectral and (or) structural information in areas of limited bedrock outcrop to aid in regional geologic interpretation. Only the first four of these objectives are addressed here. About 170 Landsat computer-compatible tapes covering Victoria Land, the coastline of West Antarctica, the Antarctic Peninsula, and other selected areas were assembled into false-color, multi-spectral, digital composites of band 4 (0.5 to 0.6 μm, green), band 5 (0.6 to 0.7 μm, red) and band 7 (0.8 to 1.1 μm, near infra-red). The tapes were subjected to routine image-processing procedures, such as noise removal and radiometric and geometric corrections. Further processing included haze removal and enhancement by linear stretching of individual MSS bands based on inspection of gray-value (digital-number) histograms. Saturation of snow-covered scenes in bands 4, 5, and 6 is a severe problem in Landsat MSS images of Antarctica and makes many images unsuitable for multi-spectral work. We have developed special techniques to restore the saturated snow-and-ice information in these bands to overcome this problem. The Landsat image maps have different formats, depending on their planned applications. An example of a planimetric image map is the one of the McMurdo Sound area; it is based on excellent ground control and processed at full spatial resolution. It comprises five complete and three partial 1 : 250 000 scale topographic quadrangles. One of these is the Convoy Range quadrangle which includes the Allan Hills meteorite-collection site. Blue-ice areas show exceptionally well on this quadrangle, and new information on blue-ice locations and delineations was obtained from it. Thematic maps prepared for the Byrd Glacier area selectively show only rock or ice areas, thus depicting the location of desired features. Synoptic-view maps and mosaics provide information on flow lines associated with ice streams, the location of ice rises, ice rumples, and other possible grounded areas, and the location and extent of buried mountain ranges. Image maps which cover the same area at different times do show changes: a 10-year interval between Landsat images obtained in the Byrd Glacier area shows that crevasses had opened and rifts had drifted within the floating part of the glacier; measurements of the changed positions have yielded average velocities for glacier and ice-shelf movements in that area. The ease with which the dynamics of the coastline can be monitored on Landsat images is particularly useful, because such changes have implications for variations in world climate.

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27

Lucchitta, B. K., K. Edwards, E. M. Eliason y J. Bowell. "Multi-Spectral Landsat Image Maps of Antarctica (Abstract)". Annals of Glaciology 9 (1987): 250. http://dx.doi.org/10.3189/s0260305500000926.

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The US Geological Survey is conducting a program to prepare digitally enhanced Multispectral Scanner (MSS) Landsat images of Antarctica. The goal is to furnish accurate planimetric, false-colour composite image maps in Lambert conformal conic projection for the following purposes: (1) to locate and delineate blue-ice areas for the collection of meteorites; (2) to produce special purpose maps showing selected features; (3) to provide synoptic views that aid in the detection and interpretation of glaciological features associated with the inland ice sheet, outlet glaciers, ice streams, and ice shelves; (4) to monitor changes in coastline and glacial features; (5) to enable the superposition and correlation of different types of digital cartographic data; and (6) to furnish spectral and (or) structural information in areas of limited bedrock outcrop to aid in regional geologic interpretation. Only the first four of these objectives are addressed here.About 170 Landsat computer-compatible tapes covering Victoria Land, the coastline of West Antarctica, the Antarctic Peninsula, and other selected areas were assembled into false-color, multi-spectral, digital composites of band 4 (0.5 to 0.6 μm, green), band 5 (0.6 to 0.7 μm, red) and band 7 (0.8 to 1.1 μm, near infra-red). The tapes were subjected to routine image-processing procedures, such as noise removal and radiometric and geometric corrections. Further processing included haze removal and enhancement by linear stretching of individual MSS bands based on inspection of gray-value (digital-number) histograms. Saturation of snow-covered scenes in bands 4, 5, and 6 is a severe problem in Landsat MSS images of Antarctica and makes many images unsuitable for multi-spectral work. We have developed special techniques to restore the saturated snow-and-ice information in these bands to overcome this problem.The Landsat image maps have different formats, depending on their planned applications. An example of a planimetric image map is the one of the McMurdo Sound area; it is based on excellent ground control and processed at full spatial resolution. It comprises five complete and three partial 1 : 250 000 scale topographic quadrangles. One of these is the Convoy Range quadrangle which includes the Allan Hills meteorite-collection site. Blue-ice areas show exceptionally well on this quadrangle, and new information on blue-ice locations and delineations was obtained from it.Thematic maps prepared for the Byrd Glacier area selectively show only rock or ice areas, thus depicting the location of desired features. Synoptic-view maps and mosaics provide information on flow lines associated with ice streams, the location of ice rises, ice rumples, and other possible grounded areas, and the location and extent of buried mountain ranges. Image maps which cover the same area at different times do show changes: a 10-year interval between Landsat images obtained in the Byrd Glacier area shows that crevasses had opened and rifts had drifted within the floating part of the glacier; measurements of the changed positions have yielded average velocities for glacier and ice-shelf movements in that area. The ease with which the dynamics of the coastline can be monitored on Landsat images is particularly useful, because such changes have implications for variations in world climate.

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28

BOTTA, Oliver, Zita MARTINS, Christian EMMENEGGER, Jason P. DWORKIN, Daniel P. GLAVIN, Ralph P. HARVEY, Renato ZENOBI, Jeffrey L. BADA y Pascale EHRENFREUND. "Polycyclic aromatic hydrocarbons and amino acids in meteorites and ice samples from LaPaz Icefield, Antarctica". Meteoritics & Planetary Science 43, n.º 9 (septiembre de 2008): 1465–80. http://dx.doi.org/10.1111/j.1945-5100.2008.tb01021.x.

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29

Liu, Jian-Zhong, Yong-Liao Zou, Chun-Lai Li, Lin Xu y Zi-Yuan Ouyang. "A Study on the Recovery and Classification of Meteorites from the Mt. Grove Region of Antarctica". Chinese Journal of Astronomy and Astrophysics 4, n.º 2 (abril de 2004): 166–75. http://dx.doi.org/10.1088/1009-9271/4/2/166.

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30

Drewry, David J. "The future of Antarctic scientific research". Polar Record 29, n.º 168 (enero de 1993): 37–44. http://dx.doi.org/10.1017/s0032247400023196.

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ABSTRACTWithin the stable political context of the Antarctic Treaty regime, science has flourished, achieving considerable prominence and an increasing global relevance. Issues such as stratospheric ozone depletion and enhanced ultraviolet effects, environmental and climatic archive from ice cores, detection of anthropogenic pollution, study of global climate change (such as the carbon cycle and sea level), and analysis of unique collections of meteorites have attracted and focused unprecedented international attention on Antarctica. In the future, major challenges will continue to emerge in Antarctic science, driven by conceptual breakthroughs, innovative field research, and rapidly developing technology. Today's fashionable topics such as global wanning, biodiversity, thecarbon pump, and ozone loss may soon fade. What will replace them remains uncertain. The study of the coupling of presently diverse whole-earth systems appears a possibility: the biogeochemical coupling of landmasses, oceans, and ice geared to the study and provision of new food resources, to meet the demands of a world population in exponential growth, will feature considerably in the next century and involve much Antarctic research. Future science will develop against a backdrop of heightening external pressures: (1) the competing demands from the AntarcticTreaty System, including environmental concerns and possible operating restrictions, and the requirement to provide expert opinion from specialised research, (2) increasing problems of the coordination of an expanding and diverse scientific community, (3) the high cost and level of sophistication of modern research, and (4) accountability, particularly in respect of quality scientific results. Within each of these areas national programmes will assess and determine priorities for the future, which will severely test existing systems for collaboration, logistics sharing, and financial underpinning. Attention will need to be directed at a critical evaluation of the international mechanisms and frameworks for establishing the details of the Antarctic scientific agenda, and its meshing with discipline-based research in general.

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31

Day, James M. D., Lawrence A. Taylor, Christine Floss, Allan D. Patchen, Darren W. Schnare y D. Graham Pearson. "Comparative petrology, geochemistry, and petrogenesis of evolved, low-Ti lunar mare basalt meteorites from the LaPaz Icefield, Antarctica". Geochimica et Cosmochimica Acta 70, n.º 6 (marzo de 2006): 1581–600. http://dx.doi.org/10.1016/j.gca.2005.11.015.

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32

Huss, Gary R. "Meteorite mass distributions and differences between Antarctic and non-Antarctic meteorites". Geochimica et Cosmochimica Acta 55, n.º 1 (enero de 1991): 105–11. http://dx.doi.org/10.1016/0016-7037(91)90404-s.

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33

Marvin, Ursula B. y Glenn J. MacPherson. "Field and Laboratory Investigations of Meteorites from Victoria Land and the Thiel Mountains Region, Antarctica, 1982-1983 and 1983-1984". Smithsonian Contributions to the Earth Sciences, n.º 28 (1989): 1–146. http://dx.doi.org/10.5479/si.00810274.28.1.

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34

Hallis, L. J. "Alteration assemblages in the Miller Range and Elephant Moraine regions of Antarctica: Comparisons between terrestrial igneous rocks and Martian meteorites". Meteoritics & Planetary Science 48, n.º 2 (25 de enero de 2013): 165–79. http://dx.doi.org/10.1111/maps.12049.

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35

Evatt, G. W., A. R. D. Smedley, K. H. Joy, L. Hunter, W. H. Tey, I. D. Abrahams y L. Gerrish. "The spatial flux of Earth’s meteorite falls found via Antarctic data". Geology 48, n.º 7 (29 de abril de 2020): 683–87. http://dx.doi.org/10.1130/g46733.1.

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Abstract Contemporary calculations for the flux of extraterrestrial material falling to the Earth’s surface (each event referred to as a “fall”) rely upon either short-duration fireball monitoring networks or spatially limited ground-based meteorite searches. To date, making accurate fall flux estimates from the much-documented meteorite stranding zones of Antarctica has been prohibited due to complicating glacial ice dynamics and difficulties in pairing together distinct meteorite samples originating from the same fall. Through glaciological analysis and use of meteorite collection data, we demonstrate how to overcome these barriers to making flux estimates. Furthermore, by showing that a clear latitudinal variation in fall frequencies exists and then modeling its mathematical form, we are able to expand our Antarctic result to a global setting. In this way, we hereby provide the most accurate contemporary fall flux estimates for anywhere on Earth. Inverting the methodology provides a valuable tool for planning new meteorite collection missions to unvisited regions of Antarctica. Our modeling also enables a reassessment of the risk to Earth from larger meteoroid impacts—now 12% higher at the equator and 27% lower at the poles than if the flux were globally uniform.

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36

Paul, Rick L. y Michael E. Lipschutz. "Labile Trace Elements in Some Antarctic Carbonaceous Chondrites: Antarctic and Non-Antarctic Meteorite Comparisons". Zeitschrift für Naturforschung A 44, n.º 10 (1 de octubre de 1989): 979–87. http://dx.doi.org/10.1515/zna-1989-1010.

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Abstract We report data for Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, TI, U and Zn determined by radiochemical neutron activation analysis in consortium samples of Belgica (B) 7904, Yamato (Y) 82042, Yamato 82162 and Yamato 86720 carbonaceous chondrites. These trace elements cover a wide volatility/mobility range and give unique information on thermal histories of meteorites. The results indicate the unique nature of these carbonaceous chondrites. Y-82042 proves to have the volatile element pattern of a C2 ( ≡CM) chondrite and the petrologic characteristics of a CI (n≡CI) chondrite. These must be primary nebular condensation/accretion features, unaffected by post-accretionary processes. The other three meteorites were thermally metamorphosed in ≧2 parent regions over the 600-700 °C range, at relative temperatures B-7904 < Y-82162< Y-86720. Before heating, B-7904 and Y-86720 had C2-levels of volatile elements: Y-82162 had uniquely high volatile element concentrations, at about CI-levels. The data require a new classification scheme for such chondrites. Belgica 7904 and Y-82162 and -86720 seem to be derived from one or more thermally altered carbonaceous asteroids, and their spectral characteristics should be compared with those of B-, F-, G- or T-asteroids. These results indicate substantial differences in the thermal histories of Antarctic and non-Antarctic CI and C2 chondrite populations. In reviewing all that is known about the Antarctic and non-Antarctic meteorite populations, the overwhelming weight of evidence supports the view that these populations sample different extraterrestrial source materials, differing in thermal histories. It may be that over the extended collecting period of the Antarctic ice sheet, it has sampled a considerably greater proportion of near-Earth asteroids than do current falls.

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37

Wasson, John T., Xinwei Ouyang, Jianmin Wang y Jerde Eric. "Chemical classification of iron meteorites: XI. Multi-element studies of 38 new irons and the high abundance of ungrouped irons from Antarctica". Geochimica et Cosmochimica Acta 53, n.º 3 (marzo de 1989): 735–44. http://dx.doi.org/10.1016/0016-7037(89)90016-1.

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38

Minami, M. y T. Nakamura. "An Extraction System to Measure Carbon-14 Terrestrial Ages of Meteorites with a Tandetron AMS at Nagoya University". Radiocarbon 43, n.º 2A (2001): 263–69. http://dx.doi.org/10.1017/s0033822200038091.

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We have constructed a system to extract carbon from meteorites using a vacuum-tight RF melting method in order to study radiocarbon activities in meteorites. The extraction system was examined using iron standards of known carbon content. The carbon extraction efficiencies and 14C ages of the iron standards by this method were compared with the results obtained previously by our older melting system and a wet oxidation method. Higher collection efficiencies of about 90% for the iron samples of relatively high carbon content were achieved by the new system. The efficiency of extracting a small amount of carbon is also near 90% after improving the extraction procedure. The 14C ages of the iron standards were compared to the ages by the wet method. The results indicate that contamination by modern carbon is negligible in the system. Furthermore, terrestrial 14C ages of two Antarctic meteorites, Y-75102 and ALH-77294, from the Yamato and Allan Hills ice fields, respectively, were determined. The age of Y-75102 is estimated 4.0 ± 1.0 ka, and the age of ALH-77294 is 19.5 ± 1.2 ka. The 14C ages on the meteorites roughly agree with the literature value. However, further study is needed in improvement on reducing a background value and of complete fusion of a meteorite in the extraction system.

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39

Tanbakouei, Safoura, Josep M. Trigo-Rodríguez, Jürgen Blum, Iwan Williams y Jordi Llorca. "Comparing the reflectivity of ungrouped carbonaceous chondrites with those of short-period comets like 2P/Encke". Astronomy & Astrophysics 641 (septiembre de 2020): A58. http://dx.doi.org/10.1051/0004-6361/202037996.

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Aims. The existence of asteroid complexes produced by the disruption of these comets suggests that evolved comets could also produce high-strength materials able to survive as meteorites. We chose as an example comet 2P/Encke, one of the largest object of the so-called Taurid complex. We compare the reflectance spectrum of this comet with the laboratory spectra of some Antarctic ungrouped carbonaceous chondrites to investigate whether some of these meteorites could be associated with evolved comets. Methods. We compared the spectral behaviour of 2P/Encke with laboratory spectra of carbonaceous chondrites. Different specimens of the common carbonaceous chondrite groups do not match the overall features and slope of the comet 2P/Encke. By testing anomalous carbonaceous chondrites, we found two meteorites: Meteorite Hills 01017 and Grosvenor Mountains 95551, which could be good proxies for the dark materials that formed this short-period comet. We hypothesise that these two meteorites could be rare surviving samples, either from the Taurid complex or another compositionally similar body. In any case, it is difficult to get rid of the effects of terrestrial weathering in these Antarctic finds, and further studies are needed. A future sample return from the so-called dormant comets could also be useful to establish a ground truth on the materials forming evolved short-period comets. Results. As a natural outcome, we think that identifying good proxies of 2P/Encke-forming materials might have interesting implications for future sample-return missions to evolved, potentially dormant, or extinct comets. Understanding the compositional nature of evolved comets is particularly relevant in the context of the future mitigation of impact hazard from these dark and dangerous projectiles.

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40

TAKEDA, Hiroshi. "Antarctic Meteorites". Journal of Geography (Chigaku Zasshi) 95, n.º 7 (1987): 559–70. http://dx.doi.org/10.5026/jgeography.95.7_559.

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41

Lorenzetti, Silvio, Yangting Lin, Daode Wang y Otto Eugster. "Noble gases and mineralogy of meteorites from China and the Grove Mountains, Antarctica: A 0.05 Ma cosmic ray exposure age of GRV 98004". Meteoritics & Planetary Science 38, n.º 8 (agosto de 2003): 1243–53. http://dx.doi.org/10.1111/j.1945-5100.2003.tb00310.x.

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42

Sandford, Scott A. "Concentrating Antarctic meteorites on blue ice fields-The Frontier Mountain meteorite trap". Meteoritics & Planetary Science 37, n.º 2 (febrero de 2002): 151. http://dx.doi.org/10.1111/j.1945-5100.2002.tb01100.x.

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43

Dartois, E., C. Engrand, J. Duprat, M. Godard, E. Charon, L. Delauche, C. Sandt y F. Borondics. "Dome C ultracarbonaceous Antarctic micrometeorites". Astronomy & Astrophysics 609 (enero de 2018): A65. http://dx.doi.org/10.1051/0004-6361/201731322.

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Context. UltraCarbonaceous Antarctic MicroMeteorites (UCAMMs) represent a small fraction of interplanetary dust particles reaching the Earth’s surface and contain large amounts of an organic component not found elsewhere. They are most probably sampling a contribution from the outer regions of the solar system to the local interplanetary dust particle (IDP) flux. Aims. We characterize UCAMMs composition focusing on the organic matter, and compare the results to the insoluble organic matter (IOM) from primitive meteorites, IDPs, and the Earth. Methods. We acquired synchrotron infrared microspectroscopy (μFTIR) and μRaman spectra of eight UCAMMs from the Concordia/CSNSM collection, as well as N/C atomic ratios determined with an electron microprobe. Results. The spectra are dominated by an organic component with a low aliphatic CH versus aromatic C=C ratio, and a higher nitrogen fraction and lower oxygen fraction compared to carbonaceous chondrites and IDPs. The UCAMMs carbonyl absorption band is in agreement with a ketone or aldehyde functional group. Some of the IR and Raman spectra show a C≡N band corresponding to a nitrile. The absorption band profile from 1400 to 1100 cm-1 is compatible with the presence of C-N bondings in the carbonaceous network, and is spectrally different from that reported in meteorite IOM. We confirm that the silicate-to-carbon content in UCAMMs is well below that reported in IDPs and meteorites. Together with the high nitrogen abundance relative to carbon building the organic matter matrix, the most likely scenario for the formation of UCAMMs occurs via physicochemical mechanisms taking place in a cold nitrogen rich environment, like the surface of icy parent bodies in the outer solar system. The composition of UCAMMs provides an additional hint of the presence of a heliocentric positive gradient in the C/Si and N/C abundance ratios in the solar system protoplanetary disc evolution.

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44

RUSSELL, SARA. "Meteorites, Ice and Antarctica: a personal account by William A. Cassidy Cambridge University Press, Cambridge (2003) ISBN 0 52125872 3. 349 pages. Price £19.95". Antarctic Science 16, n.º 1 (27 de febrero de 2004): 87. http://dx.doi.org/10.1017/s0954102004211841.

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45

Benoit, P. H. "Meteorites as surface exposure time markers on the blue ice fields of Antarctica: Episodic ice flow in Victoria land over the last 300,000 years". Quaternary Science Reviews 14, n.º 5 (enero de 1995): 531–40. http://dx.doi.org/10.1016/0277-3791(95)00011-d.

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46

D'Orazio, Massimo, Luigi Folco, Kees C. Welten, Marc W. Caffee, Natale Perchiazzi y Pierre Rochette. "Miller Butte 03002: a new rare iron meteorite (IID) from Antarctica". European Journal of Mineralogy 18, n.º 6 (20 de diciembre de 2006): 727–38. http://dx.doi.org/10.1127/0935-1221/2006/0018-0727.

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47

Zhang, Chuantong, Bingkui Miao, Huaiyu He, Hongyi Chen, P. M. Ranjith y Qinglin Xie. "A Petrologic and Noble Gas Isotopic Study of New Basaltic Eucrite Grove Mountains 13001 from Antarctica". Minerals 11, n.º 3 (9 de marzo de 2021): 279. http://dx.doi.org/10.3390/min11030279.

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Howardite-Eucrite-Diogenite (HED) meteorite clan is a potential group of planetary materials which provides significant clues to understand the formation and evolution of the solar system. Grove Mountains (GRV) 13001 is a new member of HED meteorite, recovered from the Grove Mountains of Antarctica by the Chinese National Antarctic Research Expedition. This research work presents a comprehensive study of the petrology and mineralogy, chemical composition, noble gas isotopes, cosmic-ray exposure (CRE) age and nominal gas retention age for the meteorite GRV 13001. The output data indicate that GRV 13001 is a monomict basaltic eucrite with typical ophitic/subophitic texture, and it consists mainly of low-Ca pyroxene and plagioclase with normal eucritic chemical compositions. The noble gas based CRE age of the GRV 13001 is approximately 29.9 ± 3.0 Ma, which deviates from the major impact events or periods on the HED parent body. Additionally, the U,Th-4He and 40K-40Ar gas retention ages of this meteorite are ~2.5 to 4.0 Ga and ~3.6 to 4.1 Ga, respectively. Based on the noble gases isotopes and the corresponding ages, GRV 13001 may have experienced intense impact processes during brecciation, and weak thermal event after the ejection event at approximately 30 Ma.

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48

Genge, Matthew J. "Book Review: William A. Cassidy (ed.): Meteorites, Ice, and Antarctica: A personal Account, Cambridge University Press, 2003, ISBN: 0-521-25872-0 hardback, Price:GBP 19.95/US$ 30.00." Earth, Moon, and Planets 93, n.º 3 (noviembre de 2003): 233. http://dx.doi.org/10.1023/b:moon.0000047517.67734.df.

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49

Genge, Matthew J. "Book Review: William A. Cassidy (ed.): Meteorites, Ice, and Antarctica: A personal Account, Cambridge University Press, 2003, ISBN: 0-521-25872-0 hardback, Price:GBP 19.95/US$ 30.00." Earth, Moon, and Planets 93, n.º 3 (noviembre de 2003): 233. http://dx.doi.org/10.1007/s11038-004-0916-0.

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50

Drewry, D. J. "Workshop on Antarctic meteorites". Polar Record 22, n.º 141 (septiembre de 1985): 706–7. http://dx.doi.org/10.1017/s0032247400006458.

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