Abundances and isotopic compositions of rare gases in granites.

Superheavy elements in nature? Fissiogenic xenon in Sudbury, Ontario, norite.

“…o : Belgian Congo pitchblende (WETHERILL, 1953). 22 It was noted that xenon fractions with strange isotopic compositions are released also from Wausau, Wisconsin, granite, when the data recently obtained by KURODA et al (1977) and HENNECKE et al (1978) were re-examined, as shown in Table 2. The isotopic compositions of these xenon fractions lie within a triangle drawn in Fig.…”

“…The experimental procedure employed was essentially the same as that described previously (KURODA et al, 1977). A 17.971-gram sample was taken for the mass-spectrometric analysis.…”

“…We recently reported that a large fraction of the total xenon released from a sample of Red Rock granite from Sudbury, Ontario, Cana da, at 200'C appears to be a mixture of average carbonaceous chondrite (AVCC) xenon and the atmospheric xenon (KURODA et al, 1977). The Sudbury structure is believed to have been formed by the impact of an asteroid in an event that formed a crater 30 miles in diameter 1,720 million years ago (DIETZ, 1964;FRENCH, 1967).…”

Isotopic compositions of xenon and krypton in Belgian Congo pitchblende.

“…The experimental procedure employed was essentially the same as that described previously (KURODA et al, 1977 The values of A i were re-normalized to A132 = 1 .000 and are shown in Figs. 1, 2, and 3 in the form of three-isotope plots 134Xe/132Xe versus 136Xe/132Xe, 131Xe/132Xe versus 136Xe/ 132Xe and 129Xe/132Xe versus 136Xe/132Xe , respec tively.…”

The occurrence of CCFX xenon in the earth's interior.

“…The two granitoid samples, Pikes Peak batholith and the 1,600'C fraction of the Red Rock granite (Kuroda et al, 1977), are interesting in that the 124Xe/126Xe and 136Xe/134Xe ratios are both (1) Allende 4C56 (Lewis et al, 1977) 400 800 1,000 enhanced and their isotopic compositions resemble those of the xenon fractions released from the Allende residue 4C56. Enhanced 136Xe/134Xe ratios observed in the terrestrial rock samples can be easily explained, however, as due to the presence of fissiogenic xenon isotopes from 238U and the isotopic composi tions of the trapped xenon in the samples of batholith and granite can be shown to be quite similar to those of the xenon fractions released from, for example, the Allende residue BA4-Q.…”