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47 the atomic abundances of the other lead isotopes assuming that the Canyon Diablo lead has the primitive composition suid list these in the third and fourth lines of the table. The values secured are more approximate than Indicated. TABLE 6 p^204 Bfe206 pfe207 pfeSOS Average radiogenic lead (1) 9"8? 5-50 9.14 Canyon Diablo lead 1 9,50 10.36 29.49 Solar abundances of primeval 0.00288 0.0276 O.O303 O.O867 lead, ppm Atomic abundances of 0,00214 0.0203 0.0222 O.O631 primeval lead If Patterson's lead isotope ratios for Nuovo Laredo had been used instead of those of Modoc and Forest City our lead abundances would be lower and there is no certainty that chondritic meteorites will not be found with lead isotopic ratios giving higher abundances of primeval lead, Urey^s estimate for uranium depends on the heat balance of the earth, moon and Ms,rs and cannot change much due to futu2?e uranium determinations unless his arguments are shown to be incorrect. The Noddacks give 0.144 for the atomic abundance of bismuth. Its geochemical distribution has not been carefully studied. We adopt the somev/hat smaller value of 0,08, which with Pb^7 and our choice of thallium gives a smooth curve connecting the odd mass nuclides. Mostly the older analytical values for rare elements are too high and hence this lower value may be Justified,
48 We adopt values for u235, u^^° and Th^^^ by calculating the amounts of these nuclides at 4.5 x lO^years ago from Urey's (1955) estimate of their present concentrations. The values so secured are 0^0121, 0.0423 and O.O858, respectively. These are minimum values for the abundances when the elements were first synthesized, since this time was probably more than 4-5 x 10^ years ago. If we do not decrease the observed uranium and thorium abundauices by a factor of 302 as required by Urey's argument, the Pb, Tl, Bi and Hg abundances must all be raised by this factor. We believe that the observed data on BI and Hg are not good enough to give any weight to any possible decision in regard to this question. Since thallium is concentrated at the earth's surface, its abundance in the chondritic meteorites gives no evidence in regard to this question. The Age of the Elements As is well known the elements cannot be older than the time required for the production of all Pb^^^ from U^^^. The ratio of lead to uranium in a sample of material in which this ratio has not changed since the formation of the elements gives the necessary data for a valid calculation. By using the Patterson et al. (1955) data on Forest City, Modoc, Canyon Diablo and Henbury meteorites for the lead abundances, we have the necessary data. The time calculated from this data to produce the Pb^7 of the Iron meteorites is 1,07 x 10^ years and this gives 5»57 x lo9 as the
Page 1 and 2: 05" 9003'9 ,^ r.V- ou 15 -^ CBNTiJA
Page 3 and 4: DISCLAIMER Portions of this documen
Page 5 and 6: o which states that the elements wi
Page 7 and 8: inattention will be drawn to any ev
Page 9 and 10: 6 the proportions 10:1:2- The Nodda
Page 11 and 12: 8 Just in the case of these element
Page 13 and 14: 10 spectral lines on the temperatur
Page 15 and 16: 12 have studied the iron sulfide fr
Page 17 and 18: 14 the proportion of the three phas
Page 19 and 20: 16 by more than a factor of 10, e.g
Page 21 and 22: 18 million times smaller than that
Page 23 and 24: 20 as occurs at other points in the
Page 25 and 26: 22 220 ppm relative to silicon equa
Page 27 and 28: 24 abundances, R, and column three
Page 29 and 30: 26o The heavier rare gases^ Bie rar
Page 31 and 32: 28, the amount is very constant nea
Page 33 and 34: 30o valueso This ratio is 300 hy we
Page 35 and 36: greater constancy in the copper dat
Page 37 and 38: 33 o mass curve we natst assun® ab
Page 39 and 40: 35. Noddack*s value of 1.86 for the
Page 41 and 42: 37 value. Undoubtedly a marked decr
Page 43 and 44: 3Bo meteorites. We have selected a
Page 45 and 46: 40 than that given by Noddack (1955
Page 47 and 48: 42 The average is secured by assumi
Page 49 and 50: 44 these data all appear to be doub
Page 51: 46 ppm are not presented with great
Page 55 and 56: 50 the elements were formed at leas
Page 57 and 58: i»2o for the sum of isobaric abund
Page 59 and 60: 5u« This means that the In^^^ in n
Page 61 and 62: :>6„ of the neutron excess number
Page 63 and 64: dance values fitting into the trend
Page 65 and 66: OUo 56 56 The hjalf life of m , whi
Page 67 and 68: TABLE II 6 Atomic Abundances of the
Page 69 and 70: TABLE II continued 3 45 Rh 1.3 3,5
Page 71 and 72: TABLE III Element A N I Log H H 1 H
Page 73 and 74: 21 22 23 24 25 26 27 28 29 Sc Ti V
Page 75 and 76: TABLE III Continued 5 37 Rb p- 37.
Page 77 and 78: 52 55 5^ 55 56 57 58 Te I Xe Cs Bn
Page 79 and 80: 67 Ho 68 Er 71 Lu 72 Hf 73 Ta 74 W
Page 81: TABLE III Continued 11 122 124 40 4
Page 86 and 87: Blbliography-2 Pellenberger, Th.v.,
Page 88 and 89: Pinson, W.H., Ahrens, L.H. and Fran

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