PPT-Geochronology II: U-Th-Pb

Chapter 3 UThPb Three radionuclides decaying to 3 isotopes of Pb at different rates 232 Th decays to 208 Pb with a halflife of 14 Ga 238 U decays to 206 Pb with a halflife of 447 Ga. . Chapter 4. Table 4.1. Data on Cosmogenic Nuclides. Nuclide Half-life, . yrs. . . λ. , . yr. -1. . . 14. C . 5730. . 1.21 x . 10. -3. . 3. H . 12.33. . 5.62 . x 10. -2. . 10. Be 1.50 . Geochronology Graduate Student Award Program. A new . EarthScope. educational project recommended for funding. . PIs: Becky Flowers (CU), . Jim . Metcalf (CU), . Ramon . Arrowsmith. (ASU), Blair . Chapter 2. K-. Ar. , Rb-Sr, Sm-Nd, Lu-Hf and Re-Os. Figure 2.1. Decay Systems. Geochronologists have a variety of decay systems to work with. Each is in some ways unique. Success in dating depends . on . Episyenites. in Southern New Mexico. By Adam Smith. Episyenites. Hypothesis: . Episyenites result of fenitization from fluids related to . Cambro. -Ordovician alkaline magmatism . 525-457 . Ma in . NM and CO. chronostratigraphy. . . A major goal is the development of the . geochronological. techniques necessary to produce temporal constraints with uncertainties ≤ 0.1 percent of the . radioisotopic. ages. . Recall the four forces of contemporary physical theory; we have, so-far, explored the geophysics of only two. Now lets look at the two remaining:. Weak:. mediates. . β. -decay and . β. -capture processes. )! – observations on ion microprobe geochronology using a high-brightness oxygen plasma source. .. Martin J. Whitehouse & Heejin Jeon. Swedish Museum of Natural History, Stockholm, Sweden, martin.whitehouse@nrm.se.