Geology Reference
In-Depth Information
Table 1.
Carbon isotopic composition of size fractions.
Bulk
>1000 μm
1000-500 μm
500-250 μm
250-125 μm
125-63 μm
<63 μm
Mean
+4.8
+4.0
+4.6
+4.8
+4.9
+4.9
+4.4
SD
0.3
0.7
0.5
0.4
0.5
0.3
0.5
Minimum
+3.2
+2.0
+3.4
+3.3
+3.5
+3.9
+3.4
Maximum
+5.5
+5.1
+5.6
+5.9
+5.9
+5.4
+5.5
Table 2.
Oxygen isotopic composition of size fractions.
Bulk
>1000 μm
1000-500 μm
500-250 μm
250-125 μm
125-63 μm
<63 μm
Mean
+0.4
+0.3
+0.4
+0.5
+0.4
+0.5
+0.4
SD
0.4
0.4
0.3
0.4
0.44
0.4
0.4
Minimum
0.8
0.5
0.5
0.40
0.3
0.3
0.5
Maximum
+1.8
+1.5
+2.0
+2.0
+1.7
+1.3
+2.0
13
C and
18
O in different modifi ed Dunham classifi cation.
Table 3.
The
1.5 Mud-rich
wackestone
2.5 Mud-rich
packstone
3.5 Mud-lean
packstone
2 Wackestone
3 Packstone
4 Grainstone
5 Rudstone
13
C
+4.8
+4.8
+4.8
+4.8
+5.0
+4.9
+3.7
SD
0.1
0.2
0.2
0.2
0.3
0.3
0.1
18
O
+0.5
+0.6
+0.6
+0.6
+0.4
+0.2
0.1
SD
0.3
0.4
0.4
0.3
0.5
0.4
0.2
(a)
6.0
2
5.5
250-125 μm
125-63 μm
< 63 μm
5.0
1
4.5
0
4.0
3.5
1
2
3
4
−
1
5
Mudstone
Wackestone
Packstone
Grainstone
Rudstone
Facies type
(b)
2
13
C and facies type (1 = mud,
1.5 = mud-rich wackestone, 2 = wackestone, 2.5 = mud-
rich-packstone, 3 = packstone, 3.5 = mud-lean packstone,
4 = grainstone, 5 = rudstone).
Fig. 3.
Relationship between
Bulk
>1000 μm
1
0
similar to that shown previously (Lowenstam &
Epstein, 1957; Shinn
et al.,
1989). The
13
C values
of the DIC range from +0.4 to +2.4‰ and show no
specifi c relationship with salinity (Fig. 8).
1
−
1
2
3
4
5
6
13
C (‰)
Sediment classifi cation
18
O of all samples and size frac-
tions from 2001 to 2004 cruises: (a) data from <63, 63-125
and 125-250 μm size fractions, (b) data from bulk, 250-500,
500-1000 and >1000 μm size fractions.
13
C and
Fig. 2.
Stable
The descriptions and distribution of these
facies are fully described in a companion
