Magmatic Signature in Submarine Hydrothermal Fluids Vented Offshore Ventotene and Zannone Islands (Pontine Archipelago, Central Italy)
Table 3
Chemical composition of the dissolved (D) and bubbling gases (B).
Sample ID
Site
Depth (m)
Type
Sampling method
He
H2
O2
N2
CO
CH4
CO2
1
Z1
20
D
Niskin
bdl
bdl
3.53
9.24
0.46
2
Z1
50
D
Niskin
bdl
bdl
3.36
9.66
0.48
3
Z1
80
D
Niskin
bdl
3.79
9.40
0.46
4
Z1
100
D
Niskin
bdl
bdl
3.79
9.82
0.64
5
Z1
134
D
Niskin
bdl
3.56
6.66
0.53
6
Z2
50
D
Niskin
bdl
bdl
3.74
9.56
0.42
7
Z2
80
D
Niskin
bdl
bdl
3.63
9.37
0.45
8
Z2
100
D
Niskin
bdl
bdl
4.38
9.49
bdl
0.42
9
Z2
127
D
Niskin
bdl
bdl
3.55
9.81
0.64
10
ZDA
50
D
Niskin
bdl
4.16
8.06
bdl
0.41
11
ZDA
80
D
Niskin
bdl
4.43
8.93
bdl
0.43
12
ZDA
100
D
Niskin
bdl
bdl
2.61
6.50
0.41
13
ZDA
120
D
Niskin
bdl
4.62
9.10
0.78
14
ZDA
147
D
Niskin
bdl
bdl
4.83
9.84
0.73
ASSW
4.80E‐05
4.80
9.60
1.0E‐6
0.24
17
Z2
127
B
ROV
0.016
3.410
0.985
94.62
17 Rec
Z2
127
B
ROV
—
3.353
0.986
94.68
18
Z2
125
B
ROV
15.26
77.57
9
0.145
18 Rec
Z2
125
B
ROV
—
69.31
29
0.475
19
VEN
80
B
Two-way glass bottle
bdl
0.18
1.37
0.163
98.17
11-BT1
ZGP
129
B
ROV
50.94
12-BT1
ZGP
129
B
ROV
55.08
13-BT4
ZGP
127
B
ROV
bdl
54.22
Dissolved gas concentrations are given in ccSTP per liter of seawater. Bubbling gas composition is expressed in vol%. Values for ASSW (air-saturated seawaters) are reported as reference. bdl = below detection limits (detection limits for He, H2, and CO in the ccSTP; detection limits for He and H2 in the ). Rec = recalculated concentrations; see text for details. Reactive gases and labels after Martorelli et al. [27].