Early solar system chronology

60Fe- 60Ni system, direct measurements indicate that residual heterogeneity in the distribution of these short-lived nuclides is less than 10-15% (Thrane et al., 2006 Dauphas et al., 2008). 

Constructing a self-consistent time line from the various radiochronometers is harder than it may first appear. Each sample providing a date for the time line must meet the criteria for a valid age (see Chapter 8). This is not always easy to demonstrate, in part 

Chronology of the solar system from radioactive isotopes 

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These isotopes are sometimes used as tracers of natural terrestrial processes and cycles. Long-lived isotopes, such as Rb and Sm are used for precise dating of geological samples. When the solar system formed it also contained several short-lived isotopes that have since decayed and are now extinct in natural systems. These include Al, Fe, Pu, Pd, and Al with a half-life of less than a million years is particularly important because it is a potentially powerful heat source for planetary bodies and because its existence in the early solar system places tight constraints on the early solar system chronology. 

There are two types of refractory inclusions calcium- and aluminum-rich inclusions (this section) and amoeboid olivine aggregates (Section 1.07.5.3). Since the mineralogy, chemistry and isotope chemistry of refractory inclusions were reviewed by MacPherson et al. (1988), many new analyses have been made of CAIs in CV, CM, CO, CR, CH, CB, ordinary and enstatite chondrites that provide important constraints on physicochemical conditions, time, and place of CAI formation. CAIs are addressed in detail in Chapter 1.08, the role of condensation and evaporation in their formation in Chapter 1.15, and their clues to early solar system chronology in Chapter 1.16. 

Gilmour JD, Whitby JA, Turner G, Bridges JC, Hutchison R (2000) The iodine-xenon system in clasts and chondrules from ordinary chondrites implications for early Solar System chronology. Meteoritic Planet Sci 35 445-455... 

Yin, Q.Z., Jacobsen, S.B., Blichert-Toft, J., Telouk, P., and AlbarMe, F. (2001) Nb-Zr and HT-W isotope systematics applications to early solar system chronology and planetary differentiation, 32nd Lunar and Planetary Science Conference, 12-16 March 2001, Houston, TX, Abstract 2128. 

D., Leya, I., and Mezger, K. (2010) Non-nucleosynthetic heterogeneity in non-radiogenic stable Hf isotopes implications for early solar system chronology. Earth Planet. Sci. Lett., 295, 1-11. 

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