An Evaluation of the Long-Term Stagnancy of Porewater in the Neogene Sedimentary Rocks in Northern Japan
Table 3
Comparison of and ; was calculated from (10) and was calculated by the multiplication of the accumulation rate of 4He by radiogenic effects (calculated in Section 5.2.2) and time (1.0 million years).
Name of borehole
(m)
Formation
Remarks
×10−6
×10−6
HDB-9
−77.5
W
0.97
1.19
1.38
−226.2
W
0.98
6.12
2.57
−267.5
W
0.98
5.66
2.30
−367.5
W
0.98
5.03
2.57
−460.2
W
0.95
0.13
2.63
HDB-10
134.5
K
0.97
2.44
1.19
42.6
K
0.97
2.72
2.20
−58.5
W
0.97
1.64
2.57
−174.0
W
El-(a)
−222.0
W
0.96
5.23
1.95
HDB-11
389.6
K
0.99
2.31
0.81
278.8
K
0.98
1.16
1.23
171.5
K
0.99
1.77
1.36
83.0
K
El-(a)
−100.0
W
0.99
3.14
3.23
−226.1
W
0.98
21.45
2.57
−301.0
W
El-(b)
−345.1
W
El-(b)
−396.3
W
El-(b)
−445.4
W
El-(b)
−496.3
W
El-(b)
−547.5
W
El-(b)
HCD-2
−73.0
W
0.93
8.88
2.77
−101.9
W
0.93
4.75
2.57
−136.4
W
0.92
12.76
3.02
−171.3
W
0.93
10.40
2.57
−220.1
W
2.83
El-(a)
−268.5
W
0.93
7.79
−297.6
W
0.94
13.42
2.23
−303.3
W
0.94
13.97
2.57
−306.9
W
0.94
13.02
2.57
−313.6
W
0.95
19.02
2.64
−316.7
W
0.94
6.27
2.57
−318.0
W
0.95
24.78
2.81
average value of the Koetoi Formation or the Wakkanai Formation; El-(a): eliminated because of high Ne concentration; El-(b): eliminated because bubble was observed on surface in the sampling.
