| Unit and locality(b) | Method | Number of samples(c} | Age (Ga)(d) | Source |
| WEST GREENLAND | ||||
| Qôrqut granite | ||||
| Godthaab | Rb-Sr | 23w | 2.53 ± 0.03 | Moorbath, Taylor, and Goodwin, 1981 |
| Rb-Sr | 3m | 2.52 ± 0.03 | Pankhurst et al., 1973 | |
| Pb-Pb | 23w | 2.58 ± 0.08 | Moorbath, Taylor, and Goodwin, 1981 | |
| U-Pb | 7z | 2.53 ± 0.03 | Baadsgaard, 1976 | |
| Nûk gneisses (and equivalents) |
||||
| Bjorneoen | Pb-Pb | 11w | 3.02 ± 0.26 | P. N. Taylor et al., 1980 |
| Rb-Sr | 11w | 2.98 ± 0.05 | P. N. Taylor et al. 1980 | |
| Rb-Sr | 14w | 2.94 ± 0.09 | P. N. Taylor et al., 1980; Moorbath and Pankhurst 1976; Pankhurst, Moorbath, and McGregor, 1973 | |
| Rb-Sr | 6w | 3.08 ± 0.03 | Baadsgaard and McGregor, 1981 | |
| Buksefjord | Rb-Sr | 21w | 2.86 ± 0.09 | P. N. Taylor et al., 1980; Moorbath and Pankhurst 1976 |
| Faeringehavn | Rb-Sr | 8w | 2.73 ± 0.06 | Moorbath and Pankhurst, 1976 |
| Fiskenaesset | Pb-Pb | 9w | 2.82 ± 0.07 | P. N. Taylor et al., 1980 |
| U-Pb | 5z | 2.80 ± 0.10 | Pidgeon, Aftalion, and Kalsbeek, 1976 | |
| Rb-Sr | 11w | 2.84 ± 0.07 | P. N. Taylor et al., 1980; Moorbath and Pankhurst, 1976 | |
| Fredrikshaabs isblink | Rb-Sr | 13w | 2.60 ± 0.12 | Moorbath and Pankhurst, 1976; Pidgeon and Hopgood, 1975 |
| Godthaab | U-Pb | 5z | 2.82 ± 0.05 | Baadsgaard, 1976 |
| Rb-Sr | 11w | 2.77 ± 0.19 | P. N. Taylor et al., 1980; Moorbath and Pankhurst 1976 | |
| Godthaabsfjord | Rb-Sr | 11w | 2.86 ± 0.30 | P. N. Taylor et al., 1980; Moorbath and Pankhurst 1976 |
| Itivinga Nordland Sermilik |
Rb-Sr | 6w | 2.86 ± 0.06 | P. N. Taylor et al., 1980 |
| Pb-Pb | 19w | 3.00 ± 0.07 | P. N. Taylor et al., 1980 | |
| Pb-Pb | 11w | 3.00 ± 0.09 | P. N. Taylor et al., 1980 | |
| Rb-Sr | 20w | 2.75 ± 0.04 | P. N. Taylor et al., 1980; Moorbath and Pankhurst 1976 | |
| Layered anorthosite | ||||
| Fiskenaesset | Rb-Sr | 4w | 2.75 ± 0.24 | Alexander, Evensen, and Murthy, 1973 |
| Ar-Ar | 1w | 2.83 ± 0.08 | Alexander, Evensen, and Murthy, 1973 | |
| South of Godthaab | Pb-Pb | 15w | 2.76 ± 0.14 | P. N. Taylor et al., 1980 |
| Amîtsoq gneisses | ||||
| Godthaab | U-Pb | 9z | 3.60 ± 0.05 | Baadsgaard, 1973, 1976 |
| U-Pb | 8z | 3.60 | Michard-Vitrac et al., 1977 | |
| Pb-Pb | 13w | 3.56 ± 0.10 | Black et al.,1971 | |
| Isua | Pb-Pb | 9w | 3.74 ± 0.12 | Moorbath, O'Nions, and Pankhurst, 1975 |
| Rb-Sr | 13w | 3.64 ± 0.06 | Moorbath, O'Nions, and Pankhurst, 1975; Moorbath et al., 1977a | |
| Rb-Sr | 12w | 3.62 ± 0.14 | Moorbath et al., 1972 | |
| Narssaq | Rb-Sr | 25w | 3.67 ± 0.09 | Moorbath et al., 1972 |
| Narssaq, Qilangarssuit, Isua | Lu-Hf | 9w, z | 3.55 ± 0.22 | Pettingill and Patchett, 1981 |
| Praestefjord | Rb-Sr | 18w | 3.61 ± 0.22 | Moorbath et al., 1972 |
| Qilangarssuit | Rb-Sr | 7w | 3.66 ± 0.10 | Moorbath et al., 1972 |
| Simiutat | Pb-Pb | 7w | 3.62 ± 0.13 | Griffin et al., 1980 |
| Rb-Sr | 7w | 3.56 ± 0.14 | Griffin et al., 1980 | |
| Early supracrustals | ||||
| Various units, Isua Conglomerate | U-Pb | 16z | 3.81 ± 0.02 | Baadsgaard et al., 1984 |
| U-Pb | 8z | 3.77 ± 0.01 | Michard-Vitrac et al., 1977 | |
| Rb-Sr | 8w | 3.66 ± 0.06 | Moorbath, O'Nions, and Pankhurst, 1975; Moorbath et al., 1977a | |
| Rb-Sr | 5w | 3.71 ± 0.07 | Jacobsen and Dymek, 1988 | |
| Garbenschiefer + conglomerate | Sm-Nd | 12w | 3.75 ± 0.04 | Hamilton et al., 1983 |
| Iron formation | Pb-Pb | 11w | 3.70 ± 0.07 | Moorbath, O'Nions, and Pankhurst, 1973 |
| Akilia association, Akilia |
U-Pb | 11z | 3.59 ± 0.04 | Baadsgaard et a1., 1984 |
| LABRADOR | ||||
| Post-tectonic granite | ||||
| Saglek | U-Pb | 4z | 2.52 | Baadsgaard, Collerson, and Bridgwater, 1979 |
| Younger gneisses | ||||
| Ikarut, Hebron | Rb-Sr | 7w | 2.77 ± 0.14 | Collerson, Kerr, and Compston, 1981 |
| Kammersuit, Nachvak | Rb-Sr | 6w | 2.69 ± 0.14 | Collerson, Kerr, and Compston, 1981 |
| Granitic sheets, Saglek | Rb-Sr | 21w | 2.81 ± 0.21 | Collerson, Kerr, and Compston, 1981 |
| Kiyuktok, Saglek | Pb-Pb | 5w | 3.50 ± 0.11 | Collerson, Kerr, and Compston, 1981 |
| Rb-Sr | 15w | 2.75 ± 0.12 | Collerson, Kerr, and Compston, 1981 | |
| Rb-Sr | 6w | 3.06 ± 0.16 | Hurst et al., 1975 | |
| Civak gneisses | ||||
| Saglek, Maidmonts Is. | U-Pb | 3z | 3.76 ± 0.15 | Winless, Bridgwater, and Collerson, 1979 |
| Saglek | Rb-Sr | 7w | 3.55 ± 0.07 | Hurst et al., 1975 |
| Hebron | Rb-Sr | 8w | 3.56 ± 0.08 | Barton, 1982 |
| Saglek and Hebron (plus Amîtsoq)(e) various |
Rb-Sr | 21w | 3.61 ± 0.20 | M. Cameron et al., 1981 |
| Sm-Nd | 28w | 3.56 ± 0.20 | Collerson, McCulloch, and Miller, 1981 | |
Note: Units within an area, e.g., West Greenland, are listed in stratigraphic order when this order is known. All of the ages are based on isochron (Rb-Sr, Sm-Nd, Lu-Hf), concordia-discordia (U-Pb), or age-spectrum (Ar-Ar) techniques.
(a) From Dalrymple, G. Brent. 1991. “The Age of the Earth”. Stanford University Press. Copyright © 1991 by the Board of Trustees of the Leland Stanford Junior University.
(b) Localities are approximate as samples are generally collected over a broad area.
(c) w, whole rock; z, zircon; m, various minerals from same rock.
(d) All ages calculated with the decay constants in Table 3.1. Errors are at the 95% confidence level (two standard deviations).
(e) Combined isochron using 18 Uivak samples and 10 Amîtsoq samples.
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