CHAPTER 6 . Diagenesis of Organic Matter at the Water-Sediment Interface
J3-aminoglutaric / glutamic acid ratio
o 0.2
0.4
0.6
0.8
1.0
1.2
01
ix
Lf
0
10
20
E 30
~
.s::.
a IV
o 40
50
60
70
X
.0
X <»
OX.
"(5- l
+
+
+
X
0
+ STA4
o STA5A
X STA6
o STA8
• STA2A
o
o
X +
X
o
+
X +
0+
o
+
1.4
159
1.6
1.8
o
o
X
o
+0
o
+
+
Fig. 6.8. Variation in the relative abundance of dissolved free glutamic acid and J3-aminoglutaric acid
in sediment cores from the Peru upwelling region (redrawn from Henrichs et al. 1984)
Fig. 6.9. Ratios of unsaturated
fatty acids to their saturated
counterparts in sediments of
Lake Haruna, Japan (adapted
from Kawamura et al.1980)
3
5
~ 7
.t:
a 9
IV
~ 11
813
15
Ratio of unsaturated to saturated fatty acid
0.1
0.5
1
Lake Haruna
a- , ,
." , " , 0
if"'
."
o
\
b
.0"
18:3
18:2 16:1
18:1
18:0
18:0 16:0 18:0
'0
.5
_-0
able to organic geochemists. Sterols are more reactive than bulk ~C, such that sterol
concentrations decrease during diagenesis relative to total organic carbon. However,
sterols are generally less reactive than fatty acids and alcohols. Sterol diagenesis is often