Table 11. Results of headspace gas analyses of sediments from Hole 1079A.
Core, section,
interval (cm)
Depth
(mbsf)
C1
(ppmv)
CO2
(ppmv)
C2=
(ppmv)
C2
(ppmv)
C3
(ppmv)
C1/C2
175-1079A-
1H-2, 0-5 1.50 4.2 1,002        
1H-4, 0-5 4.50 3.9 1,230 0.1      
2H-3, 0-5 8.30 3.8 2,741        
3H-4, 0-5 19.30 8.7 5,148        
4H-4, 0-5 28.60 10.1 11,672   0.2   50
5H-4, 0-5 38.10 41.8 12,002   0.7   60
6H-4, 0-5 47.70 37,736 13,402 0.1 8.9 0.5 4,240
7H-4, 0-5 57.40 29,589 14,375 0.2 9.8 1.3 3,019
8H-3, 0-5 65.30 10,851 35,672   9.8 1.8 1,107
9H-3, 0-5 74.80 9,080 33,264 0.1 6.8 1.5 1,335
10H-5, 0-5 86.29 8,280 37,144 0.1 6.9 2.2 1,200
11H-4, 0-5 95.20 8,658 46,628 0.1 12.0 3.4 722
12H-4, 0-5 104.70 5,854 54,410 0.1 6.0 1.7 976
13H-4, 0-5 112.80 8,391 42,124 0.1 4.7 1.2 1,785
14H-3, 0-5 120.10 3,101 24,281 0.1 2.8 0.8 1,108

Notes: C1 = methane; CO2 = carbon dioxide; C2= = ethene; C2 = ethane; and C3 = propane. Dominance of C1 over C2 indicates that the gases originate from in situ microbial degradation of organic matter.