Oxygen isotopes dust from

The finest particles composed of fine silt and clay are carried over much larger distances (Fig. 1.6). Using oxygen isotopes of aeolian quartz, it has been shown that significant quantities of dust with an average diameter of 1-10 microns are transported by jet streams from desert zones over the rest of the world. Eolian admixtures have been referred to explain the presence of Si02 in soils developed in non-quartz-containing volcanic rocks in Hawaii and Israel. 

On the basis of analyses of bulk CAIs or separated minerals, the inheritance of 0-rich condensates from supemovae appears plausible. However, the magnitude of the isotopic difference between the putative dust and gas reservoirs is a free parameter, so that the model has no predictive power. Furthermore, the observed oxygen isotope anomalies in presolar oxide grains are best understood as resulting from processing in red giant stars, and do not show 0-excesses. 

Greshake A., Hoppe P., and Bischoff A. (1996) Mineralogy, chemistry, and oxygen isotopes of refractory inclusions from stratospheric interplanetary dust particles and micrometeorites. Meteorit. Planet. Sci. 31, 739-748. 

Figure 7 The Vostok ice-core record (Petit et aL, 1999). (a)-(c) Carbon dioxide, methane, and oxygen isotope ratios (expressed as 5 0) of oxygen in air extracted from the ice. (d) Hydrogen isotope ratios (expressed as or 5D) in the ice. This record is a proxy for local temperature, (e) Sodium in the ice, a measure of sea salt aerosol deposition, (f) Dust in the ice, a measure of continental aerosol deposition, (a)-(c) are plotted against the estimated age of the iee air (d)-(f) are plotted against the estimated age of the ice.

The alternative hypothesis, that of a nucleosynthetic component carried into the early solar system by 0-rich presolar dust (see discussion in Clayton 1993) remains plausible after all, as mentioned in the Introduction, trace amounts of presolar dust is known to exist in the matrices of chondrites. However, all the high spatial (ion microprobe) measurements of the many types of primitive refractory materials discussed here have failed to find any very extreme oxygen isotopic anomalies such as might be expected if pure 0 dust (e.g. from a supernova) were incorporated into CAIs or AOAs along with local condensates. Even among the -100 true interstellar oxide grains that... 

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