Meteoritics最新文献

{"title":"An update of a catalog of Chinese meteorites","authors":"Yongheng Chen, Daode Wang","doi":"10.1111/J.1945-5100.1994.TB01103.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01103.X","url":null,"abstract":"— A catalog of Chinese meteorites is presented. The catalog updates Bian Depei's 1981 catalog and is complete through 1990 October. It includes data for 54 stone meteorites, 30 iron meteorites and a stony-iron meteorite. Many of the meteorites were previously unknown in the West.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"886-890"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01103.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63673363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Igneous petrology of the new ureilites Nova 001 and Nullarbor 010","authors":"Allan H. Triman, J. L. Berkley","doi":"10.1111/J.1945-5100.1994.TB01097.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01097.X","url":null,"abstract":"— The Nova 001 [= Nuevo Mercurio (b)] and Nullarbor 010 meteorites are ureilites, both of which contain euhedral graphite crystals. The bulk of the meteorites are olivine (Fo79) and pyroxenes (Wo9En73Fs18, Wo3En77Fs20), with a few percent graphite and minor amounts of troilite, Ni-Fe metal, and possibly diamond. The rims of olivine grains are reduced (to Fo91) and contain abundant blebs of Fe metal. Silicate mineral grains are equant, anhedral, up to 2 mm across, and lack obvious preferred orientations. Euhedral graphite crystals (to 1 mm x 0.3 mm) are present at silicate grain boundaries, along boundaries and protruding into the silicates, and entirely within silicate mineral grains. Graphite euhedra are also present as radiating clusters and groups of parallel plates grains embedded in olivine; no other ureilite has comparable graphite textures. Minute lumps within graphite grains are possibly diamond, inferred to be a result of shock. Other shock effects are limited to undulatory extinction and fracturing. Both ureilites have been weathered significantly. Considering their similar mineralogies, identical mineral compositions, and identical unusual textures, Nova 001 and Nullarbor 010 are probably paired. Based on olivine compositions, Nova 001 and Nullarbor 010 are in Group 1 (FeO-rich) of Berkley et al. (1980). Silicate mineral compositions are consistent with those of other known ureilites. The presence of euhedral graphite crystals within the silicate minerals is consistent with an igneous origin, and suggests that large proportions of silicate magma were present locally and crystallized in situ.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"843-848"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01097.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63672514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fractionated martian atmosphere in the nakhlites?","authors":"M. Drake, T. Swindle, T. Owen, D. Musselwhite","doi":"10.1111/J.1945-5100.1994.TB01099.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01099.X","url":null,"abstract":"Considerable evidence points to a martian origin of the SNC meteorites. Noble gas isotopic compositions have been measured in most SNC meteorites. The 129Xe/132Xe vs, 84Kr/132Xe ratios in Chassigny, most shergottites, and lithology C of EETA 79001 define a linear array. This array is thought to be a mixing line between martian mantle and martian atmosphere. One of the SNC meteorites, Nakhla, contains a leachable component that has an elevated 129Xe/132Xe ratio relative to its 84Kr/132Xe ratio when compared to this approximately linear array. The leachable component probably consists in part of iddingsite, an alteration product produced by interaction of olivine with aqueous fluid at temperatures lower than 150 degrees C. The elevated Xe isotopic ratio may represent a distinct reservoir in the martian crust or mantle. More plausibly, it is elementally fractionated martian atmosphere. Formation of sediments fractionates the noble gases in the correct direction. The range of sediment/atmosphere fractionation factors is consistent with the elevated 129Xe/132Xe component in Nakhla being contained in iddingsite, a low temperature weathering product. The crystallization age of Nakhla is 1.3 Ga. Its low-shock state suggests that it was ejected from near the surface of Mars. As liquid water is required for the formation of iddingsite, these observations provide further evidence for the near surface existence of aqueous fluids on Mars more recently than 1.3 Ga.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"854-9"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01099.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63672991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"What we have learned about Mars from SNC meteorites","authors":"H. McSween","doi":"10.1111/J.1945-5100.1994.TB01092.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01092.X","url":null,"abstract":"The SNC meteorites are thought to be igneous martian rocks, based on their young crystallization ages and a close match between the composition of gases implanted in them during shock and the atmosphere of Mars. A related meteorite, ALH84001, may be older and thus may represent ancient martian crust. These petrologically diverse basalts and ultramafic rocks are mostly cumulates, but their parent magmas share geochemical and radiogenic isotopic characteristics that suggest they may have formed by remelting the same mantle source region at different times. Information and inferences about martian geology drawn from these samples include the following: Planetary differentiation occured early at approximately 4.5 GA, probably concurrently with accretion. The martian mantle contains different abundances of moderately volatile and siderophile elements and is more Fe-rich than that of the Earth, which has implications for its mineralogy, density, and origin. The estimated core composition has a S abundance near the threshold value for inner core solidification. The former presence of a core dynamo may be suggested by remanent magnetization in Shergottite-Nakhlite-Chassignite (SNC) meteorites, although these rocks may have been magnetized during shock. The mineralogy of martian surface units, inferred from reflectance spectra, matches that of basaltic shergottites, but SNC lithologies thought to have crystallized in the subsurface are not presently recognized. The rheological properties of martian magmas are more accurately derived form these metorites than from observations of martian flow morphology, although the sampled range of magma compositions islimited. Estimates of planetary water abundance and the amount of outgassed water based on these meteorites are contridictory but overlap estimates based on geological observations and atmospheric measurements. Stable isotope measurements indicate that the martian hydrosphere experienced only limited exchange with the lithosphere, but it is in isotopic equilibrium with the atmosphere and has been since 1.3 Ga. The isotopically heavy atmosphere/hydrosphere composition deduced from these rocks reflects a loss process more severe than current atmospheric evolution models, and the occurence of carbonates in SNC meteorites suggest that they, rather than scapolite or hydrous carbonates, are the major crustal sink for CO2. Weathering products in SNC meteorites support the idea of limited alteration of the lithosphere by small volumes of saline, CO2-bearing water. Atmospheric composition and evolution are further constrained by noble gases in these meteorites, although Xe and Kr isotopes suggest different origins for the atmosphere. Planetary ejection of these rocks has promoted an advance in the understanding of impact physics, which has been accomplished by a model involving spallation during large cratering events. Ejection of all the SNC meteorites (except ALH84001) in one or two events may provide a plausible","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"757-779"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01092.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63672424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Alteration of calcium- and aluminium-rich inclusions in the Murray (CM2) carbonaceous chondrite","authors":"Martin R. Lee, R. Greenwood","doi":"10.1111/J.1945-5100.1994.TB01093.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01093.X","url":null,"abstract":"Four different types of calcium-and aluminium-rich inclusions (CAIs) have been identified in the CM2 chondrite Murray, three of which contain alteration products. Two types of altered CAIs, spinel inclusions and spinel-pyroxene inclusions, contain primary spinel (+/-perovskite+/-hibonite+/-diopside) and secondary Fe-rich serpentine phyllosilicates(+/-tochilinite+/-calcite). Original melilite in these CAIs is inferred to have been altered during aqueous activity in the parent body and Fe-rich serpentines, tochilinite and calcite were formed in its place. The other type of altered CAI is represented by one inclusion, here called MCA-1. This CAI contains primary spinel, perovskite, fassaite and diopside with secondary calcite, paragonite, Mg-Al-Fe phyllosilicates and a Mg-Al-Fe sulphate. Importantly, MCA-1 is similar in both primary and secondary mineralogy to a small number of altered CAIs described from other CM2 meteorites including Essebi, Murchison and a CM2 clast from Plainview. Features that these CAIs have in common include an unusually large size, CV3-like primary mineralogy and the presence of secondary aluminosilicates and calcite. The Al-rich alteration products in MCA-1 are also reminiscent of secondary minerals in refractory inclusions from CV3 meteorites, which have previously been interpreted to form by interaction of the inclusions with solar nebula gases. In common with the other types of altered CAIs in Murray, MCA-1 is inferred to have experienced its main phase of alteration in a parent body environment. The Mg-Al-Fe phyllosilicates, calcite and the Mg-Al-Fe sulphate formed following aqueous alteration of an Al-rich precursor, possibly Ca dialuminate. This episode of parent body alteration may have overprinted an earlier phase of alteration in solar nebula environment from which only paragonite remains.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"780-790"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01093.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63672509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mineralogy of new Antarctic achondrites with affinity to Lodran and a model of their evolution in an asteroid","authors":"H. Takeda, H. Mori, T. Hiroi, J. Saito","doi":"10.1111/J.1945-5100.1994.TB01096.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01096.X","url":null,"abstract":"— We studied five new Antarctic achondrites, MacAlpine Hills (MAC) 88177, Yamato (Y)74357, Y75274, Y791491 and Elephant Moraine (EET)84302 by mineralogical techniques to gain a better understanding of the mineral assemblages of a group of meteorites with an affinity to Lodran (stony-iron meteorite) and their formation processes. This group is being called lodranites. These meteorites contain major coarse-grained orthopyroxene (Opx) and olivine as in Lodran and variable amounts of FeNi metal and troilite etc. MAC88177 has more augite and less FeNi than Lodran; Y74357 has more olivine and contains minor augite; Y791491 contains in addition plagioclase. EET84302 has an Acapulco-like chondritic mineral assembladge and is enriched in FeNi metal and plagioclase, but one part is enriched in Opx and chromite. The EET84302 and MAC88177 Opx crystals have dusty cores as in Acapulco. EET84302 and Y75274 are more Mg-rich than other members of the lodranite group, and Y74357 is intermediate. Since these meteorites all have coarse-grained textures, similar major mineral assemblages, variable amounts of augite, plagioclase, FeNi metal, chromite and olivine, we suggest that they are related and are linked to a parent body with modified chondritic compositions. The variability of the abundances of these minerals are in line with a proposed model of the surface mineral assemblages of the S asteroids. The mineral assemblages can best be explained by differing degrees of loss or movements of lower temperature partial melts and recrystallization, and reduction. A portion of EET84302 rich in metal and plagioclase may represent a type of component removed from the lodranite group meteorites. Y791058 and Caddo County, which were studied for comparison, are plagioclase-rich silicate inclusions in IAB iron meteorites and may have been derived by a similar process but in a different body.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"830-842"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01096.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63672807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Meteorite falls in China and some related human casualty events","authors":"K. Yau, P. Weissman, D. Yeomans","doi":"10.1111/J.1945-5100.1994.TB01101.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01101.X","url":null,"abstract":"Statistics of witnessed and recovered meteorite falls found in Chinese historical texts for the period from 700 B.C. to A.D. 1920 are presented. Several notable features can be seen in the binned distribution as a function of time. An apparent decrease in the number of meteorite reports in the 18th century is observed. An excess of observed meteorite falls in the period from 1840 to 1880 seems to correspond to a similar excess in European data. A chi sq probability test suggest that the association between the two data sets are real. Records of human casualities and structural damage resulting from meteorite falls are also given. A calculation based on the number of casualty events in the Chinese meteorite records suggests that the probability of a meteroite striking a human is far greater than previous estimates. However, it is difficult to verify the accuracy of the reported casualty events.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"864-871"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01101.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63673140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbonates and sulfates in the Chassigny meteorite: Further evidence for aqueous chemistry on the SNC parent planet","authors":"S. Wentworth, J. Gooding","doi":"10.1111/J.1945-5100.1994.TB01100.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01100.X","url":null,"abstract":"— Scanning electron microscopy and energy-dispersive X-ray spectrometry of untreated interior chips from three different specimens of the Chassigny meteorite confirm the presence of discrete grains of Ca-carbonate, Mg-carbonate, and Ca-sulfate. Morphologies of these salt grains suggest that the Ca-carbonate is calcite (CaCO3) and that the Ca-sulfate is gypsum (CaSO4·2H2O) or bassanite (CaSO4·1/2H2O). The morphologic identification of the Mg-carbonate is equivocal, but rhombohedral and acicular crystal habits suggest magnesite and hydromagnesite, respectively. The salts in Chassigny occur as discontinuous veins in primary igneous minerals and are similar to those previously documented in the nakhlites, Nakhla and Lafayette, and in shergottite EETA79001. Unlike those in nakhlites, however, the Chassigny salts occur alone, without associated ferric oxides or aluminosilicate clays. Traces of Cl and P in Chassigny salts are consistent with precipitation of the salts from short-lived, saline, aqueous solutions that postdated igneous crystallization. In contrast with the clear case for nakhlites, stratigraphic evidence for a preterrestrial origin of the salts in Chassigny is ambiguous; however, a preterrestrial origin of the Chassigny salts best explains all available evidence. The water-precipitated salts provide clear physical evidence for the hypothesis, proposed by other workers, that the igneous amphiboles in Chassigny might have experienced isotope-exchange reactions with near-surface water, thereby compromising the original stable-isotope signature of any magmatic water in melt inclusions.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"860-863"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01100.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63673055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tunguska 95 Activities","authors":"G. Andreev","doi":"10.1111/J.1945-5100.1994.TB01107.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01107.X","url":null,"abstract":"","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"900-900"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01107.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63673084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noble gases in presolar diamonds I: Three distinct components and their implications for diamond origins","authors":"G. Huss, R. Lewis","doi":"10.1111/J.1945-5100.1994.TB01094.X","DOIUrl":"https://doi.org/10.1111/J.1945-5100.1994.TB01094.X","url":null,"abstract":"— High-purity separates of presolar diamond were prepared from 14 primitive chondrites from 7 compositional groups. Their noble gases were measured using stepped pyrolysis. Three distinct noble gas components are present in diamonds, HL, P3, and P6, each of which is found to consist of five noble gases. P3, released between 200 °C and 900 °C, has a “planetary” elemental abundance pattern and roughly “normal” isotopic ratios. HL, consisting of isotopically anomalous Xe-HL and Kr-H, Ar with high 38Ar/36Ar, and most of the gas making up Ne-A2 and He-A, is released between 1100 °C and 1600 °C. HL has “planetary” elemental ratios, except that it has much more He and Ne than other known “planetary” components. HL gases are carried in the bulk diamonds, not in some trace phase. P6 has a slightly higher median release temperature than HL and is not cleanly separated from HL by stepped pyrolysis. Our data suggest that P6 has roughly “normal” isotopic compositions and “planetary” elemental ratios. Both P3 and P6 seem to be isotopically distinct from P1, the dominant “planetary” noble-gas component in primitive chondrites. Release characteristics suggest that HL and P6 are sited in different carriers within the diamond fractions, while P3 may be sited near the surfaces of the diamonds.We find no evidence of separability of Xe-H and Xe-L or other isotopic variations in the HL component. However, because ∼1010 diamonds are required to measure a Xe composition, a lack of isotopic variability does not constrain diamonds to come from a single source. In fact, the high abundance of diamonds in primitive chondrites and the presence of at least three distinct noble-gas components strongly suggest that diamonds originated in many sources. Relative abundances of noble-gas components in diamonds correlate with degree of thermal processing (see companion paper), indicating that all meteorites sampled essentially the same mixture of diamonds. That mixture was probably inherited from the Sun's parent molecular cloud.","PeriodicalId":81993,"journal":{"name":"Meteoritics","volume":"29 1","pages":"791-810"},"PeriodicalIF":0.0,"publicationDate":"1994-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1111/J.1945-5100.1994.TB01094.X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"63672656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}