# 铀铅测年法

## 化學上的細節

$N_{\mathrm{Now}} = N_{\mathrm{Orig}} e^{-\lambda t} \,$

• $N_{\mathrm{Now}}$ 是測量時的鈾原子數量。
• $N_{\mathrm{Orig}}$ 是鈾原子原始數量，相等於測量時鈾和鉛原子的總量。
• $\lambda$ 是鈾的衰變率。
• $t$ 是鋯石的年齡，即需要測定的變量。

$N_\mathrm{U} = \left( N_\mathrm{U} + N_\mathrm{Pb} \right) e^{-\lambda_\mathrm{U} t} \,$

${{N_\mathrm{U}}\over{N_\mathrm{U} + N_\mathrm{Pb}}} = e^{-\lambda_\mathrm{U} t} \,$

$1 + {{N_\mathrm{Pb}}\over{N_\mathrm{U}}} = e^{\lambda_\mathrm{U} t} \,$

${{^\text{206}\,\!\text{Pb}^*}\over{^\text{238}\,\!\text{U}}}=e^{\lambda_{238}t}-1$

(1)

${{^\text{207}\,\!\text{Pb}^*}\over{^\text{235}\,\!\text{U}}}=e^{\lambda_{235}t}-1$

(2)

## 參考資料

1. ^ Boltwood, B.B., 1907, On the ultimate disintegration products of the radio-active elements. Part II. The disintegration products of uranium: American Journal of Science 23: 77-88.
2. ^ Parrish, Randall R.; Noble, Stephen R., 2003. Zircon U-Th-Pb Geochronology by Isotope Dilution – Thermal Ionization Mass Spectrometry (ID-TIMS). In Zircon (eds. J. Hanchar and P. Hoskin). Reviews in Mineralogy and Geochemistry, Mineralogical Society of America. 183-213.
3. ^ uranium. Columbia Electronic Encyclopedia 6th. Columbia University Press.
4. ^ 4.0 4.1 Romer, R.L. 2003. Alpha-recoil in U-Pb geochronology: Effective sample size matters. Contributions to Mineralogy and Petrology 145, (4): 481-491.
5. ^ U–Th–Pb Geochronology. Blair Schoene, Princeton University, Princeton, NJ, USA
6. ^ Patterson, C.C. (1956). Age of meteorites and the Earth. Geochim. Cosmochim. Acta 10, 230-7
7. ^ 7.0 7.1 Zircon Chronology: Dating the Oldest Material on Earth
8. ^ Dating minerals by ID-TIMS geochronology at times of in situ analysis: selected case studies from the CPGeo-IGc-USP laboratory
9. ^ Zircons, the ideal SHRIMP food
10. ^ Woodhead, J., Hellstrom, J., Maas, R., Drysdale, R., Zanchetta, G., Devine, P., Taylor, E., 2006. U-Pb geochronology of speleothems by MC-ICPMS. Quaternary Geochronology 1, 208–221.
11. ^ Lachniet, M.S., Bernal, J.P., Asmerom, Y., Polyak, V., 2012. Uranium loss and aragonite-calcite age discordance in a calcitized aragonite stalagmite. Quaternary Geochronology 14, 26–37.
12. ^ Palenik, C.S., Nasdala, L. and Ewing, R.C. (2003) Radiation damagein zircon. American Mineralogist, 88, 770-781
13. ^ Mattinson, J.M., 2005. Zircon U-Pb Chemical abrasion (“CA-TIMS”) method: Combined annealing and multi-step dissolution analysis for Improved precision and accuracy of zircon ages. Chemical Geology. 220, 47-66.
14. ^ 14.0 14.1 Dickin, A.P., 2005. Radiogenic Isotope Geology 2nd ed. Cambridge: Cambridge University Press. pp. 101.
15. ^ Vinyu, M. L.; R. E. Hanson, M. W. Martin, S. A. Bowring, H. A. Jelsma and P. H. G. M. Dirks. U-Pb zircon ages from a craton-margin archaean orogenic belt in northern Zimbabwe. Journal of African Earth Sciences. 2001, 32 (1): 103–114. Bibcode:2001JAfES..32..103V. doi:10.1016/S0899-5362(01)90021-1.
16. ^ Rollinson, Hugh R. Using geochemical data: evaluation, presentation, interpretation. Harlow: Longman. 1993. ISBN 0-582-06701-4. OCLC 27937350.[页码请求]
17. ^ Lee, James K. M.; Ian S. Williams and David J. Ellis. Pb, U and Th diffusion in natural zircon. Journal of African Earth Sciences. 2001, 390: 159–162. doi:10.1038/36554.
18. ^ The SHRIMP a window on our ancient past
19. ^ Early Earth & Zircon Research – UW-Madison (March 2014)
20. ^ Jackson, Simon E.; Norman J. Pearsona, William L. Griffin and Elena A. Belousova. The application of laser ablation-inductively coupled plasma-mass spectrometry to in situ U–Pb zircon geochronology. Chemical Geology. 2004, 211 (1-2): 47–69. doi:10.1016/j.chemgeo.2004.06.017.