Some Peculiarities of Isotopic Ratios of Noble Gases in Fossil Meteorites
نویسنده
چکیده
Introduction: More than 80 fossil meteorites have been found in the ~4 m quarry layer of midOrdovician marine limestone in southern Sweden (Thorsberg quarry) [1, 2]. The analysis of noble gas data [2] in chromite grains from these meteorites has revealed a clear negative correlation between He, Ne concentrations and mass of the samples [3]. Similar correlation has been found also for cosmicray exposure ages of fossil meteorites. The analysis of these correlations have allowed us to draw a conclusion on falling one meteoric shower but not many meteorites during several million years ~470 Ma ago [3]. Here we report some results of the analysis of a noble gas isotopic ratios according to data [2, 4].
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