Geoscience Reference
In-Depth Information
(a)
50
40
30
0
20
40
60
80
100
120
232
Th
204
Pb
(b)
40
Uranium loss
30
20
10
4
8
12
16
20
24
238
U
204
Pb
(c)
20
19
18
17
16
t = 2790
+
80 Ma
15
14
25
30
45
15
20
35
40
206
Pb
204
Pb
(d)
5
4
3
2
2.8 Ga
4.0
1
Concordia
2.0
3.0
0
0
20
40
60
80
100
120
207
Pb
235
U
