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8 Summarize the differences between16O and18O? Then explain the effects of temperature and global ice volumes on the ratio of these two isotopes (18O/16O) in ocean water and how they can be used to estimate fluctuations in temperatures and glacial ice volumes through time.
9 What is a radioactive element? What are the three major types of radioactive decay and how does each type account for the specific changes that occur when a parent isotope is converted into a daughter isotope?
10 Explain the meaning of the term half‐life of a radioactive decay process. What percentage of parent isotopes has been converted into the daughter isotope after one half‐life? After 2 half‐lives? After 3, 4, 5 and 6 half‐lives?
REFERENCES
1 Best, M.G. (2000). Igneous Petrology. New York: Wiley‐Blackwell 455 pp.
2 Dyer, M.D., Gunter, M.E., and Tasa, D. (2008). Mineralogy and Optical Mineralogy. Chantilly, VA: Mineralogical Society of America 708 pp.
3 Epstein, S. and Mayeda, T. (1953). Variation of O18 content of waters from natural sources. Geochimica et Cosmochimica Acta 4: 213–224.