2 Weathering
23
Almospheric water vapour
(61"0), ,,- 18"1,.
(6 *0), -- 16"1.
/
(6'.o), .-~4%.
,<-,~_ ~
r ,'7-"" ~
,v;,',',',',',,'.',
~
lelll tit'S" sit'#" /
"-- 11
-- l
. . . .
,,.,,,,/,../,,
. . . . . . . .
, t
( 6 0 ) p
= - 8 t..
~, ~ f
,',',,,v,v,'.','
c8"o~, .-~',..
~
\ \ " \ X ~ " "
"v',',,\x',,',,.',""
-
o ? e ~ -'~""
6 mO., 0 "/..
Fig. 2.9. Oxygen isotope fractionation during evaporation and condensation. 05180)A:
isotopic composition of atmospheric water vapour: (8180)p: isotopic composition of
precipitation. (modified after Welhan 1987)
0
-40
~C~ -80
-120
-140
-16
§
//
s
1/
, /
/
/.,,
r e /
~
100 ~
/"
/
/ /
,'/'~"3"' ~
~;'
y," ///
~,>"
/*
/ /
-12 -8
-4
0
t.
8
12
16
70
24
6 1~0
Fig. 2.10. 8D and 8180 values of hydrous minerals formed in equilibrium with meteoric
waters. (Kyser 1987)