1. Today's GeoSeminar (1:00-2:00 p.m. in Mudd 218): Dr. Karl Kreutz University of Maine, Orono Pacific Climate Variability over the Last Millennium

2. Radiocarbon Dating: The great tool of the Quaternary ( Plus a few special wrinkles in dating techniques thrown in for fun! )

4. ( WHY NOT ?? )

6. Aniakchak Volcano erupted ~3400 years ago to devastate the SW Alaskan coast.

8. Lower sediments in the section revealed that numerous volcanic ashes had buried the regional landscape previously. 11,250 +/- 50 6800 +/- 60 7900 +/- 50 8800 +/- 70 3400 +/- 80 On the southern coast, the volcanic debris thickness was only about 1 meter....

10. (Museum reconstruction of bog body burial)

11. Costs: Conventional: $345; AMS: $595 per sample

17. The density of the "tracks" through the grain is a function of its age and the uranium content.

18. Rubidium-strontium dating ( 87 Rb --> 87 Sr) is also useful for the oldest metamorphic shield rocks, and can give ages of both the parent rock and the time of metamorphism. (T 1/2 of 87 Rb is ~ 50 BILLION yrs.) Uranium-series dating (relying on intermediate decay products) can be used sometimes to determine ages of corals, sedimentary units or soils up to 500,000 years old.

19. Chemistry of the Earth and an Introduction to Minerals Coming Monday: