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Presolar grains mineralogy

We should also address the question of whether Cl chondrites represent the complete, low-temperature condensate from the solar nebula. Their bulk composition is consistent with such a model. However, Cl chondrites contain among the highest abundances of presolar grains that are not destroyed by aqueous alteration (the mineralogy of Cl chondrites is almost entirely due to such alteration). This suggests that it is more likely that Cl chondrites formed from representative samples of the dust inherited from the Sun s parent... [Pg.204]

Presolar grains are found in small quantities (with concentrations of ppb to several 100 ppm, see Table 2.1) in all types of primitive Solar System materials (Lodders Amari 2005 Zinner 2007). This includes primitive meteorites (the chondrites), IDPs, some of which might originate from comets, Antarctic micrometeorites (AMMs), and samples from comet Wild 2 collected by NASA s Stardust mission. Presolar grains are nanometer to micrometer in size. The isotopic compositions, chemistry, and mineralogy of individual grains with sizes >100 nm can be studied in the laboratory. Important analysis techniques are secondary ion mass spectrometry (SIMS) and resonance ionization mass spectrometry (RIMS)... [Pg.41]

Calcium-aluminum-rich refractory inclusions (CAIs) in chondrites are the oldest Solar System solids (2-3 Myr older than chondrules, see Chapters 1 and 9). The mineralogy, petrographic, chemical, and isotopic characteristics of these primitive solids constrain the physical and chemical processes through which these materials have been processed (Zhu et al. 2001 Becker Walker 2003 Biz-zarro et al. 2004 Chaussidon et al. 2008). The primordial presolar grains were... [Pg.110]

Chondrite matrices are also the carriers of presolar grains. These phases cover a broad mineralogy and include diamonds and graphite, silicon carbide (SiC), titanium carbide (TiC), silicon nitride (SisN, ), corundum, spinel, silicates, and even rare metal grains. [Pg.338]


See other pages where Presolar grains mineralogy is mentioned: [Pg.129]    [Pg.130]    [Pg.201]    [Pg.412]    [Pg.28]    [Pg.165]    [Pg.167]    [Pg.412]    [Pg.145]    [Pg.180]    [Pg.187]    [Pg.699]    [Pg.701]    [Pg.202]    [Pg.179]    [Pg.683]    [Pg.288]   
See also in sourсe #XX -- [ Pg.127 ]




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Mineralogical

Presolar grain

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