Its strong radiogenic
lead enrichment suggests a source that is enriched in U relative to Pb (Chauvel et al.
Very little radiogenic
daughter [sup.40]Ar is incorporated into most minerals when they crystallize because argon is an inert gas that is typically excluded from their crystal structures.
In addition, there is a problem of logical inconsistency if the government continues to assert that CLL is nonradiogenic whereas SLL is radiogenic
. Contemporary classification schemes hold that B-cell CLL and SLL are analogous diseases and should be considered as a single disease entity.
As for basement rocks, previous studies  confirm that these granites commonly contain relatively higher radioactive U, Th, and K contents, giving a weighted mean radiogenic
heat production rate of 6.77 [micro]W/[m.sup.3], which provides superior conditions for geothermal resources.
isotopes: systematics and applications to earth surface processes and chemical stratigraphy.
(1971); Abbreviations: Z--zircon euh-- euhedral; subh--subhedral; eq--equant; pr--prism; clr--colourless; lbr--light brown; mf-muItifaceted; incl--inclusions; 2:1, 3:l, etc.-- length:breadth ratio; Number in brackets indicates number of grains analysed; Th/U//based on radiogenic
[sup.208]Pb/[sup.206]Pb ratio and [sup.207]pb/[sup.206]Pb age; Conamon Pb//total common Pb, blank isotopic composition: [sup.206]Pb/[sup.204]Pb = 18.221, [sup.207]Pb/ [sup.204]Pb = [sup.207]Pb/[sup.204Pb = 15.612, [sup.208]Pb/ [sup.204]Pb = 39.36; discord//percent discordance for the given [sup.207]Pb/[sup.206] Pb age.
isotopes of the Estonian and Latvian rapakivi suites: new data from the concealed Precambrian of the East European Craton.
There are chapters on biostratigraphy 3), orbital parameters and cycle stratigraphy 4), geomagnetic polarity 5), radiogenic
isotopes 6), strontium isotopes 7), and geomathematics 8).
As shown in Table 13, these data indicate a considerable reduction in sensitivity for radiogenic
cancer induction with advancing age.
Meanwhile, the contribution of regional sedimentary rocks is conjectured by the Zn-Pb-S isotopes: (1) the Zn isotopic variation range of sulfides (-0.25 [per thousand]~0.03 [per thousand]) is larger than basement rocks (0.05 [per thousand]~0.21 [per thousand]); (2) the radiogenic
Pb isotopic compositions of sulfides (e.g., [sup.2]06Pb/[sup.204]Pb = 18.727~19.896) is higher than regional igneous rocks ([sup.206]Pb/[sup.204]Pb = 18.4~19.2); (3) the [delta][sup.34] S values of sulfides (6 [per thousand]~12 [per thousand]) are lighter than regional sedimentary wall rocks (10.94 [per thousand]~11.49 [per thousand]) but higher than mantle value (0 [+ or -] 2 [per thousand]).