Table 2. Relative abundance of functional genes from IODP Expedition 305 rock samples 90 and 142.
| Gene Category | Rock sample 90 (% relative abundance) | Rock sample 142 (% relative abundance) |
| Organic contaminant degradation | 34.19 | 44.62 |
| Metal toxicity | 16.13 | 18.73 |
| Carbon degradation(*) | 14.19 | 7.17 |
| Denitrification(*) | 10.97 | 6.37 |
| Nitrogen mineralization(*) | 3.23 | 2.39 |
| Sulfate reduction(*) | 4.52 | 4.38 |
| Nitrogen fixation(*) | 4.52 | 1.99 |
| Carbon fixation(*) | 3.23 | 2.39 |
| Methane oxidation(*) | 3.23 | 1.99 |
| Cytochrome | 1.94 | 2.79 |
| Methane generation | 0.65 | 0.80 |
| Nitrification(*) | 0.65 | 0.00 |
Gene categories that have a higher relative abundance in rock sample 90 compared to rock sample 142 are denoted by*.