U-Th-Pb Decay Systems 9/9/10 - ppt video online download

U-Th-Pb Decay Systems 9/9/10 - ppt video online download: Why are zircons and galenas Introduction to U, Th, and Pb Element Charge Radius (Å) U +4 (+6) oxic 1.05 Th Pb Th and U are highly incompatible and thus are concentrated in crustal materials and depleted in mantle Material U(ppm) Th Pb Chondrites Troilite Basalt Galena trace trace HUGE Zircon HUGE HUGE trace Carbonates Seawater (surface) 3 ppb 20 fg/g 2.7 pg/g Seawater (deep) 3 ppb 60 fg/g 5 pg/g Why are zircons and galenas the poster-children Of U-Th-Pb dating?