Calcium-aluminum-rich inclusions

Huss GR, MacPherson GJ, Wasserburg GJ, Russell SS, Srinivasan G (2001) Aluminum-26 in calcium-aluminum-rich inclusions and chondrales from unequilibrated ordinary chondrites. Meteorit Planet Sci... [Pg.59]

MacPherson GJ, Huss GR, Davis AM (2003) Extinct Be in type A calcium-aluminum-rich inclusions from CV chondrites. Geochim Cosmochim Acta 67 3615-3179 Matthews GJ, Cowan JJ (1990) New insights into the astrophysical r-process. Nature 345 491-494 McCulloch MT, Wasserburg GJ (1978a) Barium and neodymium isotopic anomalies in the Allende meteorite. Astrophys J 220 L15-L19... [Pg.61]

Laser ablation combined with LA-MC-ICPMS provides a new dimension to the analysis of Mg isotopes in calcium aluminum-rich inclusions from primitive meteorites. Dispersion in 26Mg - Al/ Mg evolution lines can be correlated with mass-dependent variahons in 5 Mg that distinguish open-system from closed-system processes. The ultimate product of such studies will be a better understanding of the chronological significance of variations in Mg in these objects. [Pg.229]

Richter EM, Davis AM, Ebel DS, Hashimoto A (2002) Elemental and isotopic fractionation of type B calcium-aluminum-rich inclusions Experiments, theoretical considerations, and constraints on their thermal evolution. Geochim Cosmochim Acta 66(3) 521-540... [Pg.230]

Russell SS, Huss GR, Fahey AJ, Greenwood RC, Hutchison R, Wasserburg GJ (1998) An isotopic and petrologic study of calcium-aluminum-rich inclusions from C03 meteorites. Geochim Cosmochim Acta 62(4) 689-714... [Pg.230]

Richter FM, Davis AM, Ehel DS, Hashimoto A (2002) Elemental and isotopic fractionation of Type B calcium-, aluminum-rich inclusions Experiments, theoretical considerations, and constraints on their thermal evolution. Geochim Cosmochim Acta 66 521-540 Richter FM, Davis AM, DePaolo DJ, Watson EB (2003) Isotope fractionation by chemical diffusion between molten basalt and rhyolite. Geochim Cosmochim Acta 67 3905-3923 Rudnick RL, Fountain DM (1995) Nature and composition of the continental crust—a lower crustal perspective. Rev Geophys 33 267-309... [Pg.287]

Figure 5-9 Al- Mg isochron for a calcium-aluminum-rich inclusion (CAI) E60. The initial isotopic ratio of (26ai/27ai)o 4,52 X 10 . Adapted from Amelin et al. (2002).

Amelin Y., Krot A.N., Hutcheon I.D., and Ulyanov A.A. (2002) Lead isotopic ages of chondrules and calcium-aluminum-rich inclusions. Science 297, 1678-1683. [Pg.593]

McKeegan, K. D., Chaussidon, M. and Robert, F. (2000) Incorporation of short-lived 10Be in a calcium-aluminum-rich inclusion from the Allende meteorite. Science, 289, 1334-1337. [Pg.304]

MacPherson, G. J., Simon, S. B., Davis, A. M., Grossman, L. and Krot, A.N. (2005) Calcium-aluminum-rich inclusions major unanswered questions. In Chondrites and the Protoplanetary Disk, ASP Conference Series, 341, eds. Krot, A. N., Scott, E. R. D. and Reipurth, A. San Francisco Astronomical Society of the Pacific, pp. 225-250. [Pg.516]

Calcium-aluminum-rich inclusions The CAIs reveal a lot of isotopic action in calcium. But 4°Ca itself is taken as a reference for other isotopes because it is the most abundant. What is measured is the ratio of the other Ca isotope abundances to that of 4°Ca therefore attribution of an anomalous isotopic ratio to an anomaly in 4°Ca abundance is seldom made. Because of systematic linear variations with isotopic mass of the measured isotopic abundances, moreover, it is common to remove that effect by defining the ratio 44Ca/4°Ca as normal, a doubtful procedure, but common. Anomalies in other Ca isotopes thus appear as deviations from the linear slope set by the 44Ca/4°Ca ratio. All this is to say that a self-consistent analysis of the entire Ca suite is required. [Pg.187]

Calcium-aluminum-rich inclusions After systematic linear variations with isotopic mass (mass fractionation) of the measured isotopic abundances has been removed by defining the ratio 44Ca/4°Ca as normal, anomalies in the 42Ca/4°Ca ratio are found. Both excesses and deficits of 42Ca have been recognized in this way, but no larger than about 0.2%. Based on a few CAIs the 42Ca excess (or deficiency) seems to correlate with whether 4 Ca is in excess or deficient. [Pg.191]

Calcium-aluminum-rich inclusions (CAIs) Isotopic anomalies for 49Ti are observed in certain types of CAI ( FUN inclusions). These anomalies occur as either an excess or as a deficit of 49Ti. These are also seen in smaller hibonite crystals (Ca-Al... [Pg.210]

Calcium-aluminum-rich inclusions (see Glossary) also contain53 Cr variations that are smaller than those of 54Cr. These may be 53Mn-derived or intrinsic isotopic patterns. [Pg.223]

Calcium-aluminum-rich inclusions (CAIs) After removing the progressive mass-dependent fractionation that occurs in the measuring process and in the formation process for the samples, isotopic anomalies for 66Zn are observed in certain... [Pg.267]

The most primitive chondrites consist of coarse-grained (mm-sized) mineral assemblages embedded in fine-grained (10 nm-5 pm) matrix material (see Fig. 1.2). The coarse-grained chondritic components are diverse in their composition and mineralogy and include calcium-aluminum-rich inclusions (CAIs), amoeboid olivine aggregates (AOAs), Al-rich chondrules, Fe-Mg chondrules, Fe-rich metals, and iron sulfides. The CAIs are composed largely of calcium, aluminum, and titanium... [Pg.3]

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